Breaking update

- Added: Optionals for the missing JDK ones. - Removed: Default values for Reduce and FindFirst. Using Optionals instead.
Switched to yearly activity
2026-05-11 18:00:00 +02:00 · 2026-05-11 00:36:08 +02:00
35 changed files with 598 additions and 298 deletions
--- a/README.md
+++ b/README.md
@ -2,7 +2,7 @@
 [![Latest Release](https://jitpack.io/v/Speiger/Primitive-Collections.svg)](https://jitpack.io/#Speiger/Primitive-Collections)
 ![Maven Central Version](https://img.shields.io/maven-central/v/io.github.speiger/Primitive-Collections)
 [![License](https://img.shields.io/badge/License-Apache_2.0-blue.svg)](https://opensource.org/licenses/Apache-2.0)
-![GitHub commit activity](https://img.shields.io/github/commit-activity/m/Speiger/Primitive-Collections)      
+![GitHub commit activity](https://img.shields.io/github/commit-activity/y/Speiger/Primitive-Collections)      
 ![Unit Tests](https://github.com/Speiger/Primitive-Collections/actions/workflows/build_tests_action.yml/badge.svg)
 ![Coverage](https://gist.githubusercontent.com/Speiger/280257cd19cbe1dda3789bebd4ff65cf/raw/jacoco.svg)
 [![codecov](https://codecov.io/gh/Speiger/Primitive-Collections/branch/debug/graph/badge.svg?token=WSTSNJM0EN)](https://codecov.io/gh/Speiger/Primitive-Collections)
--- a/src/builder/java/speiger/src/builder/modules/FunctionModule.java
+++ b/src/builder/java/speiger/src/builder/modules/FunctionModule.java
@ -34,7 +34,8 @@ public class FunctionModule extends BaseModule
 	protected void loadBlockades()
 	{
 		if(keyType.isObject()) addBlockedFiles("Consumer", "Comparator");
-		if(!MODULE.isEnabled()) addBlockedFiles("Consumer", "BiConsumer", "Comparator", "Supplier", "Function", "UnaryOperator");
+		if(!MODULE.isEnabled()) addBlockedFiles("Consumer", "BiConsumer", "Comparator", "Supplier", "Optional", "Function", "UnaryOperator");
+		if(!keyType.needsCustomJDKType()) addBlockedFiles("Optional");
 	}
 	
 	@Override
@ -60,6 +61,7 @@ public class FunctionModule extends BaseModule
 		}
 		else addBiRequirement("Function");
 		addRemapper("BiConsumer", "%sConsumer");
+		addRemapper("Optional", "Optional%s");
 	}
 	
 	@Override
@ -94,6 +96,8 @@ public class FunctionModule extends BaseModule
 		
 		addFunctionMappers("PREDICATE", "%sPredicate");
 		addClassMapper("SUPPLIER", "Supplier");
+		addSimpleMapper("OPTIONAL", keyType.isObject() ? "Optional" : String.format("Optional%s", keyType.getFileType()));
+		addSimpleMapper("VALUE_OPTIONAL", valueType.isObject() ? "Optional" : String.format("Optional%s", valueType.getFileType()));
 		addAbstractMapper("SINGLE_UNARY_OPERATOR", "%1$s%1$sUnaryOperator");
 		addBiClassMapper("UNARY_OPERATOR", "UnaryOperator", "");
 		if(keyType.isObject())
--- a/src/builder/java/speiger/src/builder/modules/JavaModule.java
+++ b/src/builder/java/speiger/src/builder/modules/JavaModule.java
@ -60,6 +60,8 @@ public class JavaModule extends BaseModule
 		addSimpleMapper("APPLY_KEY_VALUE", keyType.isObject() ? "apply" : "applyAs"+keyType.getNonFileType());
 		addSimpleMapper("APPLY_VALUE", valueType.isObject() ? "apply" : "applyAs"+valueType.getNonFileType());
 		addSimpleMapper("APPLY_CAST", "applyAs"+keyType.getCustomJDKType().getNonFileType());
+		addSimpleMapper("GET_OPTIONAL", keyType.isObject() ? "ofNullable" : "of");
+		addSimpleMapper("GET_OPTIONAL_VALUE", valueType.isObject() ? "ofNullable" : "of");
 		
 		//Shared by Maps and Pairs so moved to java.
 		addFunctionMappers("ENTRY_KEY", "get%sKey");
--- a/src/builder/resources/speiger/assets/collections/templates/collections/Iterable.template
+++ b/src/builder/resources/speiger/assets/collections/templates/collections/Iterable.template
@ -5,6 +5,9 @@ import java.util.function.Consumer;
 #if JDK_FUNCTION
 import java.util.function.PREDICATE;
 #endif
+#if JDK_TYPE 
+import java.util.OPTIONAL;
+#endif

 #if !TYPE_OBJECT

@ -30,6 +33,9 @@ import speiger.src.collections.PACKAGE.collections.OUTPUT_ITERABLE;
 #endif
 #enditerate
 #endif
+#if !JDK_TYPE 
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#endif
 import speiger.src.collections.PACKAGE.functions.function.TO_OBJECT_FUNCTION;
 import speiger.src.collections.ints.functions.consumer.BI_FROM_INT_CONSUMER;
 import speiger.src.collections.objects.functions.consumer.BI_FROM_OBJECT_CONSUMER;
@ -408,13 +414,13 @@ public interface ITERABLE KEY_GENERIC_TYPE extends Iterable<CLASS_TYPE>
 	 * @param filter that should be applied
 	 * @return the found value or the null equivalent variant.
 	 */
-	default KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+	default OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 		Objects.requireNonNull(filter);
 		for(ITERATOR KEY_GENERIC_TYPE iter = iterator();iter.hasNext();) {
 			KEY_TYPE entry = iter.NEXT();
-			if(filter.test(entry)) return entry;
+			if(filter.test(entry)) return OPTIONAL.GET_OPTIONAL(entry);
 		}
-		return EMPTY_VALUE;
+		return OPTIONAL.empty();
 	}
 	
 #if !TYPE_OBJECT
@ -459,7 +465,7 @@ public interface ITERABLE KEY_GENERIC_TYPE extends Iterable<CLASS_TYPE>
 	 * @param operator the operation that should be applied
 	 * @return the reduction result, returns null value if nothing was found
 	 */
-	default KEY_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+	default OPTIONAL KEY_GENERIC_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 		Objects.requireNonNull(operator);
 		KEY_TYPE state = EMPTY_VALUE;
 		boolean empty = true;
@ -471,7 +477,7 @@ public interface ITERABLE KEY_GENERIC_TYPE extends Iterable<CLASS_TYPE>
 			}
 			state = operator.APPLY_VALUE(state, iter.NEXT());
 		}
-		return state;
+		return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 	}	
 	
 	/**
--- a/src/builder/resources/speiger/assets/collections/templates/functions/Optional.template
+++ b/src/builder/resources/speiger/assets/collections/templates/functions/Optional.template
@ -0,0 +1,89 @@
+package speiger.src.collections.PACKAGE.functions;
+
+import java.util.NoSuchElementException;
+import java.util.function.Supplier;
+
+public final class OPTIONAL KEY_GENERIC_TYPE {
+	private static final OPTIONAL NO_GENERIC_TYPE EMPTY = new OPTIONALBRACES();
+	
+	private final boolean isPresent;
+	private final KEY_TYPE value;
+	
+	private OPTIONAL() {
+		this.isPresent = false;
+		this.value = EMPTY_VALUE;
+	}
+	
+	private OPTIONAL(KEY_TYPE value) {
+		this.isPresent = true;
+		this.value = value;
+	}
+	
+	public static OPTIONAL KEY_GENERIC_TYPE empty() {
+		return EMPTY;
+	}
+	
+	public static OPTIONAL KEY_GENERIC_TYPE of(KEY_TYPE value) {
+		return new OPTIONALBRACES(value);
+	}
+	
+	public KEY_TYPE SUPPLY_GET() {
+		if(!isPresent) throw new NoSuchElementException("No value present");
+		return value;
+	}
+	
+	public boolean isPresent() {
+		return isPresent;
+	}
+	
+	public boolean isEmpty() {
+		return !isPresent;
+	}
+	
+	public void ifPresent(CONSUMER KEY_GENERIC_TYPE consumer) {
+		if(isPresent) consumer.accept(value);
+	}
+	
+    public void ifPresentOrElse(CONSUMER KEY_GENERIC_TYPE action, Runnable emptyAction) {
+        if (isPresent) action.accept(value);
+        else emptyAction.run();
+    }
+	
+	public KEY_TYPE orElse(KEY_TYPE other) {
+		return isPresent ? value : other;
+	}
+	
+	public KEY_TYPE orElseGet(SUPPLIER KEY_GENERIC_TYPE other) {
+		return isPresent ? value : other.SUPPLY_GET();
+	}
+	
+	public KEY_TYPE orElseThrow() {
+        if (!isPresent) throw new NoSuchElementException("No value present");
+		return value;
+	}
+	
+    public <X extends Throwable> KEY_TYPE orElseThrow(Supplier<? extends X> exceptionSupplier) throws X {
+    	if(isPresent) return value;
+    	else throw exceptionSupplier.get();
+    }
+    
+    @Override
+    public boolean equals(Object obj) {
+    	if(obj == this) return true;
+    	if(obj instanceof OPTIONAL) {
+    		OPTIONAL KEY_GENERIC_TYPE other = (OPTIONAL KEY_GENERIC_TYPE)obj;
+    		return (isPresent && other.isPresent ? KEY_EQUALS(value, other.value) : isPresent == other.isPresent);
+    	}
+    	return false;
+    }
+    
+    @Override
+    public int hashCode() {
+    	return isPresent ? KEY_TO_HASH(value) : 0;
+    }
+    
+    @Override
+    public String toString() {
+    	return isPresent ? "OPTIONAL["+value+"]" : "OPTIONAL.empty";
+    }
+}
--- a/src/builder/resources/speiger/assets/collections/templates/lists/ArrayList.template
+++ b/src/builder/resources/speiger/assets/collections/templates/lists/ArrayList.template
@ -7,6 +7,9 @@ import java.util.Comparator;
 import java.util.Collection;
 import java.util.Iterator;
 import java.util.Objects;
+#if JDK_TYPE
+import java.util.OPTIONAL;
+#endif
 #if TYPE_OBJECT
 #if IARRAY_FEATURE || TYPE_OBJECT
 import java.util.function.Consumer;
@ -33,6 +36,9 @@ import speiger.src.collections.PACKAGE.collections.COLLECTION;
 import speiger.src.collections.PACKAGE.collections.STACK;
 #endif
 import speiger.src.collections.PACKAGE.collections.ITERATOR;
+#if !JDK_TYPE 
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#endif
 #if !TYPE_OBJECT
 import speiger.src.collections.PACKAGE.functions.COMPARATOR;
 import speiger.src.collections.PACKAGE.functions.CONSUMER;
@ -682,12 +688,12 @@ public class ARRAY_LIST KEY_GENERIC_TYPE extends ABSTRACT_LIST KEY_GENERIC_TYPE
 	}
 	
 	@Override
-	public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+	public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 		Objects.requireNonNull(filter);
 		for(int i = 0;i<size;i++) {
-			if(filter.test(data[i])) return data[i];
+			if(filter.test(data[i])) return OPTIONAL.GET_OPTIONAL(data[i]);
 		}
-		return EMPTY_VALUE;
+		return OPTIONAL.empty();
 	}
 	
 #if !TYPE_OBJECT
@ -714,7 +720,7 @@ public class ARRAY_LIST KEY_GENERIC_TYPE extends ABSTRACT_LIST KEY_GENERIC_TYPE
 	
 #endif
 	@Override
-	public KEY_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+	public OPTIONAL KEY_GENERIC_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 		Objects.requireNonNull(operator);
 		KEY_TYPE state = EMPTY_VALUE;
 		boolean empty = true;
@ -726,7 +732,7 @@ public class ARRAY_LIST KEY_GENERIC_TYPE extends ABSTRACT_LIST KEY_GENERIC_TYPE
 			}
 			state = operator.APPLY_VALUE(state, data[i]);
 		}
-		return state;
+		return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 	}
 	
 	@Override
--- a/src/builder/resources/speiger/assets/collections/templates/lists/CopyOnWriteList.template
+++ b/src/builder/resources/speiger/assets/collections/templates/lists/CopyOnWriteList.template
@ -8,6 +8,9 @@ import java.util.Collection;
 import java.util.Iterator;
 import java.util.NoSuchElementException;
 import java.util.Objects;
+#if JDK_TYPE
+import java.util.OPTIONAL;
+#endif
 import java.util.concurrent.locks.ReentrantLock;
 import java.util.function.Consumer;
 import java.util.function.Supplier;
@ -33,6 +36,9 @@ import speiger.src.collections.PACKAGE.collections.COLLECTION;
 import speiger.src.collections.PACKAGE.collections.STACK;
 #endif
 import speiger.src.collections.PACKAGE.collections.ITERATOR;
+#if !JDK_TYPE 
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#endif
 #if !TYPE_OBJECT
 import speiger.src.collections.PACKAGE.functions.COMPARATOR;
 import speiger.src.collections.PACKAGE.functions.CONSUMER;
@ -810,13 +816,13 @@ public class COPY_ON_WRITE_LIST KEY_GENERIC_TYPE extends ABSTRACT_LIST KEY_GENER
 	}
 	
 	@Override
-	public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+	public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 		Objects.requireNonNull(filter);
 		KEY_TYPE[] data = this.data;
 		for(int i = 0,m=data.length;i<m;i++) {
-			if(filter.test(data[i])) return data[i];
+			if(filter.test(data[i])) return OPTIONAL.GET_OPTIONAL(data[i]);
 		}
-		return EMPTY_VALUE;
+		return OPTIONAL.empty();
 	}
 	
 #if !TYPE_OBJECT
@ -845,7 +851,7 @@ public class COPY_ON_WRITE_LIST KEY_GENERIC_TYPE extends ABSTRACT_LIST KEY_GENER
 	
 #endif
 	@Override
-	public KEY_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+	public OPTIONAL KEY_GENERIC_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 		Objects.requireNonNull(operator);
 		KEY_TYPE[] data = this.data;
 		KEY_TYPE state = EMPTY_VALUE;
@ -858,7 +864,7 @@ public class COPY_ON_WRITE_LIST KEY_GENERIC_TYPE extends ABSTRACT_LIST KEY_GENER
 			}
 			state = operator.APPLY_VALUE(state, data[i]);
 		}
-		return state;
+		return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 	}
 	
 	@Override
--- a/src/builder/resources/speiger/assets/collections/templates/lists/ImmutableList.template
+++ b/src/builder/resources/speiger/assets/collections/templates/lists/ImmutableList.template
@ -7,6 +7,9 @@ import java.util.Comparator;
 import java.util.Collection;
 import java.util.NoSuchElementException;
 import java.util.Objects;
+#if JDK_TYPE
+import java.util.OPTIONAL;
+#endif
 #if TYPE_OBJECT
 import java.util.function.BiFunction;
 import java.util.function.Consumer;
@ -27,6 +30,9 @@ import speiger.src.collections.PACKAGE.collections.COLLECTION;
 #if !TYPE_OBJECT
 import speiger.src.collections.PACKAGE.functions.COMPARATOR;
 import speiger.src.collections.PACKAGE.functions.CONSUMER;
+#if !JDK_TYPE 
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#endif
 import speiger.src.collections.PACKAGE.utils.ARRAYS;
 #endif
 import speiger.src.collections.objects.functions.consumer.BI_FROM_OBJECT_CONSUMER;
@ -335,12 +341,12 @@ public class IMMUTABLE_LIST KEY_GENERIC_TYPE extends ABSTRACT_LIST KEY_GENERIC_T
 	}
 	
 	@Override
-	public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+	public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 		Objects.requireNonNull(filter);
 		for(int i = 0,m=data.length;i<m;i++) {
-			if(filter.test(data[i])) return data[i];
+			if(filter.test(data[i])) return OPTIONAL.GET_OPTIONAL(data[i]);
 		}
-		return EMPTY_VALUE;
+		return OPTIONAL.empty();
 	}
 	
 #if !TYPE_OBJECT
@ -367,7 +373,7 @@ public class IMMUTABLE_LIST KEY_GENERIC_TYPE extends ABSTRACT_LIST KEY_GENERIC_T

 #endif
 	@Override
-	public KEY_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+	public OPTIONAL KEY_GENERIC_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 		Objects.requireNonNull(operator);
 		KEY_TYPE state = EMPTY_VALUE;
 		boolean empty = true;
@ -379,7 +385,7 @@ public class IMMUTABLE_LIST KEY_GENERIC_TYPE extends ABSTRACT_LIST KEY_GENERIC_T
 			}
 			state = operator.APPLY_VALUE(state, data[i]);
 		}
-		return state;
+		return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 	}
 	
 	@Override
--- a/src/builder/resources/speiger/assets/collections/templates/lists/LinkedList.template
+++ b/src/builder/resources/speiger/assets/collections/templates/lists/LinkedList.template
@ -4,7 +4,6 @@ package speiger.src.collections.PACKAGE.lists;
 #if DEQUEUE_FEATURE
 import java.util.Comparator;
 #endif
-
 import java.util.function.BiFunction;
 #else if PRIMITIVES
 import java.nio.JAVA_BUFFER;
@ -12,6 +11,9 @@ import java.nio.JAVA_BUFFER;
 import java.util.Collection;
 import java.util.Iterator;
 import java.util.Objects;
+#if JDK_TYPE
+import java.util.OPTIONAL;
+#endif
 import java.util.NoSuchElementException;
 #if SPLIT_ITERATOR_FEATURE
 import java.util.Spliterator;
@ -34,6 +36,9 @@ import java.util.function.JAVA_PREDICATE;
 #endif
 import java.util.function.JAVA_UNARY_OPERATOR;
 #endif
+#if !JDK_TYPE 
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#endif
 import speiger.src.collections.ints.functions.consumer.BI_FROM_INT_CONSUMER;
 import speiger.src.collections.objects.functions.consumer.BI_FROM_OBJECT_CONSUMER;
 #if !JDK_FUNCTION
@ -493,12 +498,12 @@ public class LINKED_LIST KEY_GENERIC_TYPE extends ABSTRACT_LIST KEY_GENERIC_TYPE
 	}
 	
 	@Override
-	public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+	public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 		Objects.requireNonNull(filter);
 		for(Entry KEY_GENERIC_TYPE entry = first;entry != null;entry = entry.next) {
-			if(filter.test(entry.value)) return entry.value;
+			if(filter.test(entry.value)) return OPTIONAL.GET_OPTIONAL(entry.value);
 		}
-		return EMPTY_VALUE;
+		return OPTIONAL.empty();
 	}
 	
 #if !TYPE_OBJECT
@ -525,7 +530,7 @@ public class LINKED_LIST KEY_GENERIC_TYPE extends ABSTRACT_LIST KEY_GENERIC_TYPE
 	
 #endif
 	@Override
-	public KEY_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+	public OPTIONAL KEY_GENERIC_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 		Objects.requireNonNull(operator);
 		KEY_TYPE state = EMPTY_VALUE;
 		boolean empty = true;
@ -537,7 +542,7 @@ public class LINKED_LIST KEY_GENERIC_TYPE extends ABSTRACT_LIST KEY_GENERIC_TYPE
 			}
 			state = operator.APPLY_VALUE(state, entry.value);
 		}
-		return state;
+		return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 	}
 	
 	@Override
--- a/src/builder/resources/speiger/assets/collections/templates/maps/impl/concurrent/ConcurrentOpenHashMap.template
+++ b/src/builder/resources/speiger/assets/collections/templates/maps/impl/concurrent/ConcurrentOpenHashMap.template
@ -4,15 +4,18 @@ import java.util.Arrays;
 import java.util.Map;
 import java.util.NoSuchElementException;
 import java.util.Objects;
+import java.util.Optional;
 import java.util.concurrent.locks.StampedLock;
 import java.util.function.Consumer;
 import java.util.function.Predicate;
 import java.util.function.BiFunction;
 #if !TYPE_OBJECT && JDK_TYPE
 import java.util.function.PREDICATE;
+import java.util.OPTIONAL;
 #endif
 #if !SAME_TYPE && JDK_VALUE && !VALUE_OBJECT
 import java.util.function.VALUE_PREDICATE;
+import java.util.VALUE_OPTIONAL;
 #endif

 #if !TYPE_OBJECT
@ -40,9 +43,12 @@ import speiger.src.collections.PACKAGE.functions.function.UNARY_OPERATOR;
 #if !SAME_TYPE
 import speiger.src.collections.PACKAGE.functions.function.SINGLE_UNARY_OPERATOR;
 #endif
-#if !TYPE_OBJECT && !VALUE_BOOLEAN && !JDK_TYPE
+#if !TYPE_OBJECT && !JDK_TYPE
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#if!VALUE_BOOLEAN
 import speiger.src.collections.PACKAGE.functions.function.PREDICATE;
 #endif
+#endif
 import speiger.src.collections.PACKAGE.maps.abstracts.ABSTRACT_MAP;
 import speiger.src.collections.PACKAGE.maps.interfaces.MAP;
 import speiger.src.collections.PACKAGE.maps.interfaces.CONCURRENT_MAP;
@ -78,6 +84,7 @@ import speiger.src.collections.objects.functions.consumer.VALUE_BI_FROM_OBJECT_C
 #endif
 #if !JDK_VALUE
 import speiger.src.collections.VALUE_PACKAGE.functions.function.VALUE_PREDICATE;
+import speiger.src.collections.VALUE_PACKAGE.functions.VALUE_OPTIONAL;
 #endif
 #endif
 #if VALUE_OBJECT
@ -839,7 +846,7 @@ public class CONCURRENT_HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY
 		}
 		
 		@Override
-		public MAP.Entry KEY_VALUE_GENERIC_TYPE reduce(ObjectObjectUnaryOperator<MAP.Entry KEY_VALUE_GENERIC_TYPE, MAP.Entry KEY_VALUE_GENERIC_TYPE> operator) {
+		public Optional<MAP.Entry KEY_VALUE_GENERIC_TYPE> reduce(ObjectObjectUnaryOperator<MAP.Entry KEY_VALUE_GENERIC_TYPE, MAP.Entry KEY_VALUE_GENERIC_TYPE> operator) {
 			Objects.requireNonNull(operator);
 			MAP.Entry KEY_VALUE_GENERIC_TYPE state = null;
 			boolean empty = true;
@ -863,11 +870,11 @@ public class CONCURRENT_HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY
 					seg.unlockRead(stamp);
 				}
 			}
-			return state;
+			return empty ? Optional.empty() : Optional.ofNullable(state);
 		}
 		
 		@Override
-		public MAP.Entry KEY_VALUE_GENERIC_TYPE findFirst(Predicate<MAP.Entry KEY_VALUE_GENERIC_TYPE> filter) {
+		public Optional<MAP.Entry KEY_VALUE_GENERIC_TYPE> findFirst(Predicate<MAP.Entry KEY_VALUE_GENERIC_TYPE> filter) {
 			Objects.requireNonNull(filter);
 			MapEntry entry = new MapEntry();
 			for(int i = 0,m=segments.length;i<m;i++) {
@ -877,7 +884,7 @@ public class CONCURRENT_HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY
 				try {
 					while(index != -1) {
 						entry.set(index, i);
-						if(filter.test(entry)) return entry;
+						if(filter.test(entry)) return Optional.ofNullable(entry);
 						index = (int)seg.links[index];
 					}
 				}
@ -885,7 +892,7 @@ public class CONCURRENT_HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY
 					seg.unlockRead(stamp);
 				}
 			}
-			return null;
+			return Optional.empty();
 		}
 		
 		@Override
@ -1186,7 +1193,7 @@ public class CONCURRENT_HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY
 		
 #endif
 		@Override
-		public KEY_TYPE reduce(SINGLE_UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+		public OPTIONAL KEY_GENERIC_TYPE reduce(SINGLE_UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 			Objects.requireNonNull(operator);
 			KEY_TYPE state = EMPTY_KEY_VALUE;
 			boolean empty = true;
@ -1210,11 +1217,11 @@ public class CONCURRENT_HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY
 					seg.unlockRead(stamp);
 				}
 			}
-			return state;
+			return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 		}
 		
 		@Override
-		public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+		public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 			Objects.requireNonNull(filter);
 			for(int i = 0,m=segments.length;i<m;i++) {
 				Segment KEY_VALUE_GENERIC_TYPE seg = segments[i];
@ -1222,7 +1229,7 @@ public class CONCURRENT_HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY
 				try {
 					int index = seg.firstIndex;
 					while(index != -1){
-						if(filter.test(seg.keys[index])) return seg.keys[index];
+						if(filter.test(seg.keys[index])) return OPTIONAL.GET_OPTIONAL(seg.keys[index]);
 						index = (int)seg.links[index];
 					}
 				}
@ -1230,7 +1237,7 @@ public class CONCURRENT_HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY
 					seg.unlockRead(stamp);
 				}
 			}
-			return EMPTY_KEY_VALUE;
+			return OPTIONAL.empty();
 		}
 		
 		@Override
@ -1454,7 +1461,7 @@ public class CONCURRENT_HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY
 		
 #endif
 		@Override
-		public VALUE_TYPE reduce(VALUE_SINGLE_UNARY_OPERATOR VALUE_VALUE_GENERIC_TYPE operator) {
+		public VALUE_OPTIONAL VALUE_GENERIC_TYPE reduce(VALUE_SINGLE_UNARY_OPERATOR VALUE_VALUE_GENERIC_TYPE operator) {
 			Objects.requireNonNull(operator);
 			VALUE_TYPE state = EMPTY_VALUE;
 			boolean empty = true;
@ -1478,20 +1485,20 @@ public class CONCURRENT_HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY
 					seg.unlockRead(stamp);
 				}
 			}
-			return state;
+			return empty ? VALUE_OPTIONAL.empty() : VALUE_OPTIONAL.GET_OPTIONAL_VALUE(state);
 		}
 		
 		@Override
-		public VALUE_TYPE findFirst(VALUE_PREDICATE VALUE_GENERIC_TYPE filter) {
+		public VALUE_OPTIONAL VALUE_GENERIC_TYPE findFirst(VALUE_PREDICATE VALUE_GENERIC_TYPE filter) {
 			Objects.requireNonNull(filter);
-			if(size() <= 0) return EMPTY_VALUE;
+			if(size() <= 0) return VALUE_OPTIONAL.empty();
 			for(int i = 0,m=segments.length;i<m;i++) {
 				Segment KEY_VALUE_GENERIC_TYPE seg = segments[i];
 				long stamp = seg.readLock();
 				try {
 					int index = seg.firstIndex;
 					while(index != -1){
-						if(filter.test(seg.values[index])) return seg.values[index];
+						if(filter.test(seg.values[index])) return VALUE_OPTIONAL.GET_OPTIONAL_VALUE(seg.values[index]);
 						index = (int)seg.links[index];
 					}
 				}
@ -1499,7 +1506,7 @@ public class CONCURRENT_HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY
 					seg.unlockRead(stamp);
 				}
 			}
-			return EMPTY_VALUE;
+			return VALUE_OPTIONAL.empty();
 		}
 		
 		@Override
--- a/src/builder/resources/speiger/assets/collections/templates/maps/impl/customHash/LinkedOpenCustomHashMap.template
+++ b/src/builder/resources/speiger/assets/collections/templates/maps/impl/customHash/LinkedOpenCustomHashMap.template
@ -4,14 +4,17 @@ import java.util.Arrays;
 import java.util.Map;
 import java.util.NoSuchElementException;
 import java.util.Objects;
+import java.util.Optional;
 import java.util.function.Consumer;
 import java.util.function.BiFunction;
 import java.util.function.Predicate;
 #if !TYPE_OBJECT && JDK_TYPE
 import java.util.function.PREDICATE;
+import java.util.OPTIONAL;
 #endif
 #if !SAME_TYPE && JDK_VALUE && !VALUE_OBJECT
 import java.util.function.VALUE_PREDICATE;
+import java.util.VALUE_OPTIONAL;
 #endif

 import speiger.src.collections.PACKAGE.collections.BI_ITERATOR;
@ -27,6 +30,7 @@ import speiger.src.collections.ints.functions.consumer.IntObjectConsumer;
 import speiger.src.collections.ints.functions.consumer.VALUE_BI_FROM_INT_CONSUMER;
 #endif
 #if !TYPE_OBJECT && !JDK_TYPE
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
 import speiger.src.collections.PACKAGE.functions.function.PREDICATE;
 #endif
 #if !TYPE_INT || !SAME_TYPE
@ -59,6 +63,7 @@ import speiger.src.collections.objects.functions.consumer.VALUE_BI_FROM_OBJECT_C
 #endif
 #if !JDK_VALUE
 import speiger.src.collections.VALUE_PACKAGE.functions.function.VALUE_PREDICATE;
+import speiger.src.collections.VALUE_PACKAGE.functions.VALUE_OPTIONAL;
 #endif
 #endif
 #if !TYPE_OBJECT
@ -873,7 +878,7 @@ public class LINKED_CUSTOM_HASH_MAP KEY_VALUE_GENERIC_TYPE extends CUSTOM_HASH_M
 		}
 		
 		@Override
-		public MAP.Entry KEY_VALUE_GENERIC_TYPE reduce(ObjectObjectUnaryOperator<MAP.Entry KEY_VALUE_GENERIC_TYPE, MAP.Entry KEY_VALUE_GENERIC_TYPE> operator) {
+		public Optional<MAP.Entry KEY_VALUE_GENERIC_TYPE> reduce(ObjectObjectUnaryOperator<MAP.Entry KEY_VALUE_GENERIC_TYPE, MAP.Entry KEY_VALUE_GENERIC_TYPE> operator) {
 			Objects.requireNonNull(operator);
 			MAP.Entry KEY_VALUE_GENERIC_TYPE state = null;
 			boolean empty = true;
@ -888,21 +893,21 @@ public class LINKED_CUSTOM_HASH_MAP KEY_VALUE_GENERIC_TYPE extends CUSTOM_HASH_M
 				state = operator.apply(state, new ValueMapEntry(index));
 				index = (int)links[index];
 			}
-			return state;
+			return empty ? Optional.empty() : Optional.ofNullable(state);
 		}
 		
 		@Override
-		public MAP.Entry KEY_VALUE_GENERIC_TYPE findFirst(Predicate<MAP.Entry KEY_VALUE_GENERIC_TYPE> filter) {
+		public Optional<MAP.Entry KEY_VALUE_GENERIC_TYPE> findFirst(Predicate<MAP.Entry KEY_VALUE_GENERIC_TYPE> filter) {
 			Objects.requireNonNull(filter);
-			if(size() <= 0) return null;
+			if(size() <= 0) return Optional.empty();
 			MapEntry entry = new MapEntry();
 			int index = firstIndex;
 			while(index != -1) {
 				entry.set(index);
-				if(filter.test(entry)) return entry;
+				if(filter.test(entry)) return Optional.ofNullable(entry);
 				index = (int)links[index];
 			}
-			return null;
+			return Optional.empty();
 		}
 		
 		@Override
@ -1160,7 +1165,7 @@ public class LINKED_CUSTOM_HASH_MAP KEY_VALUE_GENERIC_TYPE extends CUSTOM_HASH_M
 		
 #endif
 		@Override
-		public KEY_TYPE reduce(SINGLE_UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+		public OPTIONAL KEY_GENERIC_TYPE reduce(SINGLE_UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 			Objects.requireNonNull(operator);
 			KEY_TYPE state = EMPTY_KEY_VALUE;
 			boolean empty = true;
@ -1175,19 +1180,19 @@ public class LINKED_CUSTOM_HASH_MAP KEY_VALUE_GENERIC_TYPE extends CUSTOM_HASH_M
 				state = operator.APPLY_KEY_VALUE(state, keys[index]);
 				index = (int)links[index];
 			}
-			return state;
+			return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 		}
 		
 		@Override
-		public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+		public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 			Objects.requireNonNull(filter);
-			if(size() <= 0) return EMPTY_KEY_VALUE;
+			if(size() <= 0) return OPTIONAL.empty();
 			int index = firstIndex;
 			while(index != -1){
-				if(filter.test(keys[index])) return keys[index];
+				if(filter.test(keys[index])) return OPTIONAL.GET_OPTIONAL(keys[index]);
 				index = (int)links[index];
 			}
-			return EMPTY_KEY_VALUE;
+			return OPTIONAL.empty();
 		}
 		
 		@Override
@ -1343,7 +1348,7 @@ public class LINKED_CUSTOM_HASH_MAP KEY_VALUE_GENERIC_TYPE extends CUSTOM_HASH_M
 		
 #endif
 		@Override
-		public VALUE_TYPE reduce(VALUE_SINGLE_UNARY_OPERATOR VALUE_VALUE_GENERIC_TYPE operator) {
+		public VALUE_OPTIONAL VALUE_GENERIC_TYPE reduce(VALUE_SINGLE_UNARY_OPERATOR VALUE_VALUE_GENERIC_TYPE operator) {
 			Objects.requireNonNull(operator);
 			VALUE_TYPE state = EMPTY_VALUE;
 			boolean empty = true;
@ -1358,19 +1363,19 @@ public class LINKED_CUSTOM_HASH_MAP KEY_VALUE_GENERIC_TYPE extends CUSTOM_HASH_M
 				state = operator.APPLY_VALUE(state, values[index]);
 				index = (int)links[index];
 			}
-			return state;
+			return empty ? VALUE_OPTIONAL.empty() : VALUE_OPTIONAL.GET_OPTIONAL_VALUE(state);
 		}
 		
 		@Override
-		public VALUE_TYPE findFirst(VALUE_PREDICATE VALUE_GENERIC_TYPE filter) {
+		public VALUE_OPTIONAL VALUE_GENERIC_TYPE findFirst(VALUE_PREDICATE VALUE_GENERIC_TYPE filter) {
 			Objects.requireNonNull(filter);
-			if(size() <= 0) return EMPTY_VALUE;
+			if(size() <= 0) return VALUE_OPTIONAL.empty();
 			int index = firstIndex;
 			while(index != -1){
-				if(filter.test(values[index])) return values[index];
+				if(filter.test(values[index])) return VALUE_OPTIONAL.GET_OPTIONAL_VALUE(values[index]);
 				index = (int)links[index];
 			}
-			return EMPTY_VALUE;
+			return VALUE_OPTIONAL.empty();
 		}
 		
 		@Override
--- a/src/builder/resources/speiger/assets/collections/templates/maps/impl/customHash/OpenCustomHashMap.template
+++ b/src/builder/resources/speiger/assets/collections/templates/maps/impl/customHash/OpenCustomHashMap.template
@ -5,14 +5,17 @@ import java.util.ConcurrentModificationException;
 import java.util.Map;
 import java.util.NoSuchElementException;
 import java.util.Objects;
+import java.util.Optional;
 import java.util.function.Consumer;
 import java.util.function.BiFunction;
 import java.util.function.Predicate;
 #if !TYPE_OBJECT && JDK_TYPE
 import java.util.function.PREDICATE;
+import java.util.OPTIONAL;
 #endif
 #if !SAME_TYPE && JDK_VALUE && !VALUE_OBJECT
 import java.util.function.VALUE_PREDICATE;
+import java.util.VALUE_OPTIONAL;
 #endif

 #if !TYPE_OBJECT
@ -37,9 +40,12 @@ import speiger.src.collections.PACKAGE.functions.function.UNARY_OPERATOR;
 #if !SAME_TYPE
 import speiger.src.collections.PACKAGE.functions.function.SINGLE_UNARY_OPERATOR;
 #endif
-#if !TYPE_OBJECT && !VALUE_BOOLEAN && !JDK_TYPE
+#if !TYPE_OBJECT && !JDK_TYPE
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#if !VALUE_BOOLEAN
 import speiger.src.collections.PACKAGE.functions.function.PREDICATE;
 #endif
+#endif
 import speiger.src.collections.PACKAGE.maps.abstracts.ABSTRACT_MAP;
 import speiger.src.collections.PACKAGE.maps.interfaces.MAP;
 #if !TYPE_OBJECT
@ -75,6 +81,7 @@ import speiger.src.collections.objects.functions.consumer.VALUE_BI_FROM_OBJECT_C
 #endif
 #if !JDK_VALUE
 import speiger.src.collections.VALUE_PACKAGE.functions.function.VALUE_PREDICATE;
+import speiger.src.collections.VALUE_PACKAGE.functions.VALUE_OPTIONAL;
 #endif
 #endif
 import speiger.src.collections.objects.collections.ObjectIterator;
@ -1090,7 +1097,7 @@ public class CUSTOM_HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VAL
 		}
 		
 		@Override
-		public MAP.Entry KEY_VALUE_GENERIC_TYPE reduce(ObjectObjectUnaryOperator<MAP.Entry KEY_VALUE_GENERIC_TYPE, MAP.Entry KEY_VALUE_GENERIC_TYPE> operator) {
+		public Optional<MAP.Entry KEY_VALUE_GENERIC_TYPE> reduce(ObjectObjectUnaryOperator<MAP.Entry KEY_VALUE_GENERIC_TYPE, MAP.Entry KEY_VALUE_GENERIC_TYPE> operator) {
 			Objects.requireNonNull(operator);
 			MAP.Entry KEY_VALUE_GENERIC_TYPE state = null;
 			boolean empty = true;
@ -1107,25 +1114,25 @@ public class CUSTOM_HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VAL
 				}
 				state = operator.apply(state, new ValueMapEntry(i));
 			}
-			return state;
+			return empty ? Optional.empty() : Optional.ofNullable(state);
 		}
 		
 		@Override
-		public MAP.Entry KEY_VALUE_GENERIC_TYPE findFirst(Predicate<MAP.Entry KEY_VALUE_GENERIC_TYPE> filter) {
+		public Optional<MAP.Entry KEY_VALUE_GENERIC_TYPE> findFirst(Predicate<MAP.Entry KEY_VALUE_GENERIC_TYPE> filter) {
 			Objects.requireNonNull(filter);
-			if(size() <= 0) return null;
+			if(size() <= 0) return Optional.empty();
 			MapEntry entry = new MapEntry();
 			if(containsNull) {
 				entry.set(nullIndex);
-				if(filter.test(entry)) return entry;
+				if(filter.test(entry)) return Optional.ofNullable(entry);
 			}
 			for(int i = nullIndex-1;i>=0;i--) {
 				if(!strategy.equals(keys[i], EMPTY_KEY_VALUE)) {
 					entry.set(i);
-					if(filter.test(entry)) return entry;
+					if(filter.test(entry)) return Optional.ofNullable(entry);
 				}
 			}
-			return null;
+			return Optional.empty();
 		}
 		
 		@Override
@ -1331,7 +1338,7 @@ public class CUSTOM_HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VAL
 		
 #endif
 		@Override
-		public KEY_TYPE reduce(SINGLE_UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+		public OPTIONAL KEY_GENERIC_TYPE reduce(SINGLE_UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 			Objects.requireNonNull(operator);
 			KEY_TYPE state = EMPTY_KEY_VALUE;
 			boolean empty = true;
@ -1348,18 +1355,18 @@ public class CUSTOM_HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VAL
 				}
 				state = operator.APPLY_KEY_VALUE(state, keys[i]);
 			}
-			return state;
+			return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 		}
 		
 		@Override
-		public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+		public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 			Objects.requireNonNull(filter);
-			if(size() <= 0) return EMPTY_KEY_VALUE;
-			if(containsNull && filter.test(keys[nullIndex])) return keys[nullIndex];
+			if(size() <= 0) return OPTIONAL.empty();
+			if(containsNull && filter.test(keys[nullIndex])) return OPTIONAL.GET_OPTIONAL(keys[nullIndex]);
 			for(int i = nullIndex-1;i>=0;i--) {
-				if(!strategy.equals(keys[i], EMPTY_KEY_VALUE) && filter.test(keys[i])) return keys[i];
+				if(!strategy.equals(keys[i], EMPTY_KEY_VALUE) && filter.test(keys[i])) return OPTIONAL.GET_OPTIONAL(keys[i]);
 			}
-			return EMPTY_KEY_VALUE;
+			return OPTIONAL.empty();
 		}
 		
 		@Override
@ -1497,7 +1504,7 @@ public class CUSTOM_HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VAL
 		
 #endif
 		@Override
-		public VALUE_TYPE reduce(VALUE_SINGLE_UNARY_OPERATOR VALUE_VALUE_GENERIC_TYPE operator) {
+		public VALUE_OPTIONAL VALUE_GENERIC_TYPE reduce(VALUE_SINGLE_UNARY_OPERATOR VALUE_VALUE_GENERIC_TYPE operator) {
 			Objects.requireNonNull(operator);
 			VALUE_TYPE state = EMPTY_VALUE;
 			boolean empty = true;
@ -1514,18 +1521,18 @@ public class CUSTOM_HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VAL
 				}
 				state = operator.APPLY_VALUE(state, values[i]);
 			}
-			return state;
+			return empty ? VALUE_OPTIONAL.empty() : VALUE_OPTIONAL.GET_OPTIONAL_VALUE(state);
 		}
 		
 		@Override
-		public VALUE_TYPE findFirst(VALUE_PREDICATE VALUE_GENERIC_TYPE filter) {
+		public VALUE_OPTIONAL VALUE_GENERIC_TYPE findFirst(VALUE_PREDICATE VALUE_GENERIC_TYPE filter) {
 			Objects.requireNonNull(filter);
-			if(size() <= 0) return EMPTY_VALUE;
-			if(containsNull && filter.test(values[nullIndex])) return values[nullIndex];
+			if(size() <= 0) return VALUE_OPTIONAL.empty();
+			if(containsNull && filter.test(values[nullIndex])) return VALUE_OPTIONAL.GET_OPTIONAL_VALUE(values[nullIndex]);
 			for(int i = nullIndex-1;i>=0;i--) {
-				if(!strategy.equals(keys[i], EMPTY_KEY_VALUE) && filter.test(values[i])) return values[i];
+				if(!strategy.equals(keys[i], EMPTY_KEY_VALUE) && filter.test(values[i])) return VALUE_OPTIONAL.GET_OPTIONAL_VALUE(values[i]);
 			}
-			return EMPTY_VALUE;
+			return VALUE_OPTIONAL.empty();
 		}
 		
 		@Override
--- a/src/builder/resources/speiger/assets/collections/templates/maps/impl/hash/LinkedOpenHashMap.template
+++ b/src/builder/resources/speiger/assets/collections/templates/maps/impl/hash/LinkedOpenHashMap.template
@ -4,14 +4,17 @@ import java.util.Arrays;
 import java.util.Map;
 import java.util.NoSuchElementException;
 import java.util.Objects;
+import java.util.Optional;
 import java.util.function.Consumer;
 import java.util.function.BiFunction;
 import java.util.function.Predicate;
 #if !TYPE_OBJECT && JDK_TYPE
 import java.util.function.PREDICATE;
+import java.util.OPTIONAL;
 #endif
 #if !SAME_TYPE && JDK_VALUE && !VALUE_OBJECT
 import java.util.function.VALUE_PREDICATE;
+import java.util.VALUE_OPTIONAL;
 #endif

 import speiger.src.collections.PACKAGE.collections.BI_ITERATOR;
@ -27,6 +30,7 @@ import speiger.src.collections.ints.functions.consumer.IntObjectConsumer;
 import speiger.src.collections.ints.functions.consumer.VALUE_BI_FROM_INT_CONSUMER;
 #endif
 #if !TYPE_OBJECT && !JDK_TYPE
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
 import speiger.src.collections.PACKAGE.functions.function.PREDICATE;
 #endif
 #if !TYPE_INT || !SAME_TYPE
@ -58,6 +62,7 @@ import speiger.src.collections.objects.functions.consumer.VALUE_BI_FROM_OBJECT_C
 #endif
 #if !JDK_VALUE
 import speiger.src.collections.VALUE_PACKAGE.functions.function.VALUE_PREDICATE;
+import speiger.src.collections.VALUE_PACKAGE.functions.VALUE_OPTIONAL;
 #endif
 #endif
 #if !TYPE_OBJECT
@ -877,7 +882,7 @@ public class LINKED_HASH_MAP KEY_VALUE_GENERIC_TYPE extends HASH_MAP KEY_VALUE_G
 		}
 		
 		@Override
-		public MAP.Entry KEY_VALUE_GENERIC_TYPE reduce(ObjectObjectUnaryOperator<MAP.Entry KEY_VALUE_GENERIC_TYPE, MAP.Entry KEY_VALUE_GENERIC_TYPE> operator) {
+		public Optional<MAP.Entry KEY_VALUE_GENERIC_TYPE> reduce(ObjectObjectUnaryOperator<MAP.Entry KEY_VALUE_GENERIC_TYPE, MAP.Entry KEY_VALUE_GENERIC_TYPE> operator) {
 			Objects.requireNonNull(operator);
 			MAP.Entry KEY_VALUE_GENERIC_TYPE state = null;
 			boolean empty = true;
@ -892,21 +897,21 @@ public class LINKED_HASH_MAP KEY_VALUE_GENERIC_TYPE extends HASH_MAP KEY_VALUE_G
 				state = operator.apply(state, new ValueMapEntry(index));
 				index = (int)links[index];
 			}
-			return state;
+			return empty ? Optional.empty() : Optional.ofNullable(state);
 		}
 		
 		@Override
-		public MAP.Entry KEY_VALUE_GENERIC_TYPE findFirst(Predicate<MAP.Entry KEY_VALUE_GENERIC_TYPE> filter) {
+		public Optional<MAP.Entry KEY_VALUE_GENERIC_TYPE> findFirst(Predicate<MAP.Entry KEY_VALUE_GENERIC_TYPE> filter) {
 			Objects.requireNonNull(filter);
-			if(size() <= 0) return null;
+			if(size() <= 0) return Optional.empty();
 			MapEntry entry = new MapEntry();
 			int index = firstIndex;
 			while(index != -1) {
 				entry.set(index);
-				if(filter.test(entry)) return entry;
+				if(filter.test(entry)) return Optional.ofNullable(entry);
 				index = (int)links[index];
 			}
-			return null;
+			return Optional.empty();
 		}
 		
 		@Override
@ -1159,7 +1164,7 @@ public class LINKED_HASH_MAP KEY_VALUE_GENERIC_TYPE extends HASH_MAP KEY_VALUE_G
 		
 #endif
 		@Override
-		public KEY_TYPE reduce(SINGLE_UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+		public OPTIONAL KEY_GENERIC_TYPE reduce(SINGLE_UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 			Objects.requireNonNull(operator);
 			KEY_TYPE state = EMPTY_KEY_VALUE;
 			boolean empty = true;
@ -1174,19 +1179,19 @@ public class LINKED_HASH_MAP KEY_VALUE_GENERIC_TYPE extends HASH_MAP KEY_VALUE_G
 				state = operator.APPLY_KEY_VALUE(state, keys[index]);
 				index = (int)links[index];
 			}
-			return state;
+			return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 		}
 		
 		@Override
-		public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+		public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 			Objects.requireNonNull(filter);
-			if(size() <= 0) return EMPTY_KEY_VALUE;
+			if(size() <= 0) return OPTIONAL.empty();
 			int index = firstIndex;
 			while(index != -1){
-				if(filter.test(keys[index])) return keys[index];
+				if(filter.test(keys[index])) return OPTIONAL.GET_OPTIONAL(keys[index]);
 				index = (int)links[index];
 			}
-			return EMPTY_KEY_VALUE;
+			return OPTIONAL.empty();
 		}
 		
 		@Override
@ -1344,7 +1349,7 @@ public class LINKED_HASH_MAP KEY_VALUE_GENERIC_TYPE extends HASH_MAP KEY_VALUE_G
 		
 #endif
 		@Override
-		public VALUE_TYPE reduce(VALUE_SINGLE_UNARY_OPERATOR VALUE_VALUE_GENERIC_TYPE operator) {
+		public VALUE_OPTIONAL VALUE_GENERIC_TYPE reduce(VALUE_SINGLE_UNARY_OPERATOR VALUE_VALUE_GENERIC_TYPE operator) {
 			Objects.requireNonNull(operator);
 			VALUE_TYPE state = EMPTY_VALUE;
 			boolean empty = true;
@ -1359,19 +1364,19 @@ public class LINKED_HASH_MAP KEY_VALUE_GENERIC_TYPE extends HASH_MAP KEY_VALUE_G
 				state = operator.APPLY_VALUE(state, values[index]);
 				index = (int)links[index];
 			}
-			return state;
+			return empty ? VALUE_OPTIONAL.empty() : VALUE_OPTIONAL.GET_OPTIONAL_VALUE(state);
 		}
 		
 		@Override
-		public VALUE_TYPE findFirst(VALUE_PREDICATE VALUE_GENERIC_TYPE filter) {
+		public VALUE_OPTIONAL VALUE_GENERIC_TYPE findFirst(VALUE_PREDICATE VALUE_GENERIC_TYPE filter) {
 			Objects.requireNonNull(filter);
-			if(size() <= 0) return EMPTY_VALUE;
+			if(size() <= 0) return VALUE_OPTIONAL.empty();
 			int index = firstIndex;
 			while(index != -1){
-				if(filter.test(values[index])) return values[index];
+				if(filter.test(values[index])) return VALUE_OPTIONAL.GET_OPTIONAL_VALUE(values[index]);
 				index = (int)links[index];
 			}
-			return EMPTY_VALUE;
+			return VALUE_OPTIONAL.empty();
 		}
 		
 		@Override
--- a/src/builder/resources/speiger/assets/collections/templates/maps/impl/hash/OpenHashMap.template
+++ b/src/builder/resources/speiger/assets/collections/templates/maps/impl/hash/OpenHashMap.template
@ -5,14 +5,17 @@ import java.util.ConcurrentModificationException;
 import java.util.Map;
 import java.util.NoSuchElementException;
 import java.util.Objects;
+import java.util.Optional;
 import java.util.function.Consumer;
 import java.util.function.BiFunction;
 import java.util.function.Predicate;
 #if !TYPE_OBJECT && JDK_TYPE
 import java.util.function.PREDICATE;
+import java.util.OPTIONAL;
 #endif
 #if !SAME_TYPE && JDK_VALUE && !VALUE_OBJECT
 import java.util.function.VALUE_PREDICATE;
+import java.util.VALUE_OPTIONAL;
 #endif

 #if !TYPE_OBJECT
@ -37,9 +40,12 @@ import speiger.src.collections.PACKAGE.functions.function.UNARY_OPERATOR;
 #if !SAME_TYPE
 import speiger.src.collections.PACKAGE.functions.function.SINGLE_UNARY_OPERATOR;
 #endif
-#if !TYPE_OBJECT && !VALUE_BOOLEAN && !JDK_TYPE
+#if !TYPE_OBJECT && !JDK_TYPE
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#if !VALUE_BOOLEAN
 import speiger.src.collections.PACKAGE.functions.function.PREDICATE;
 #endif
+#endif
 import speiger.src.collections.PACKAGE.maps.abstracts.ABSTRACT_MAP;
 import speiger.src.collections.PACKAGE.maps.interfaces.MAP;
 #if !TYPE_OBJECT
@ -73,6 +79,7 @@ import speiger.src.collections.objects.functions.consumer.VALUE_BI_FROM_OBJECT_C

 #if !JDK_VALUE
 import speiger.src.collections.VALUE_PACKAGE.functions.function.VALUE_PREDICATE;
+import speiger.src.collections.VALUE_PACKAGE.functions.VALUE_OPTIONAL;
 #endif
 #endif
 import speiger.src.collections.objects.collections.ObjectIterator;
@ -1049,7 +1056,7 @@ public class HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_GENE
 		}
 		
 		@Override
-		public MAP.Entry KEY_VALUE_GENERIC_TYPE reduce(ObjectObjectUnaryOperator<MAP.Entry KEY_VALUE_GENERIC_TYPE, MAP.Entry KEY_VALUE_GENERIC_TYPE> operator) {
+		public Optional<MAP.Entry KEY_VALUE_GENERIC_TYPE> reduce(ObjectObjectUnaryOperator<MAP.Entry KEY_VALUE_GENERIC_TYPE, MAP.Entry KEY_VALUE_GENERIC_TYPE> operator) {
 			Objects.requireNonNull(operator);
 			MAP.Entry KEY_VALUE_GENERIC_TYPE state = null;
 			boolean empty = true;
@ -1066,25 +1073,25 @@ public class HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_GENE
 				}
 				state = operator.apply(state, new ValueMapEntry(i));
 			}
-			return state;
+			return empty ? Optional.empty() : Optional.ofNullable(state);
 		}
 		
 		@Override
-		public MAP.Entry KEY_VALUE_GENERIC_TYPE findFirst(Predicate<MAP.Entry KEY_VALUE_GENERIC_TYPE> filter) {
+		public Optional<MAP.Entry KEY_VALUE_GENERIC_TYPE> findFirst(Predicate<MAP.Entry KEY_VALUE_GENERIC_TYPE> filter) {
 			Objects.requireNonNull(filter);
-			if(size() <= 0) return null;
+			if(size() <= 0) return Optional.empty();
 			MapEntry entry = new MapEntry();
 			if(containsNull) {
 				entry.set(nullIndex);
-				if(filter.test(entry)) return entry;
+				if(filter.test(entry)) return Optional.ofNullable(entry);
 			}
 			for(int i = nullIndex-1;i>=0;i--) {
 				if(KEY_EQUALS_NOT_NULL(keys[i])) {
 					entry.set(i);
-					if(filter.test(entry)) return entry;
+					if(filter.test(entry)) return Optional.ofNullable(entry);
 				}
 			}
-			return null;
+			return Optional.empty();
 		}
 		
 		@Override
@ -1286,7 +1293,7 @@ public class HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_GENE
 		
 #endif
 		@Override
-		public KEY_TYPE reduce(SINGLE_UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+		public OPTIONAL KEY_GENERIC_TYPE reduce(SINGLE_UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 			Objects.requireNonNull(operator);
 			KEY_TYPE state = EMPTY_KEY_VALUE;
 			boolean empty = true;
@ -1303,18 +1310,18 @@ public class HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_GENE
 				}
 				state = operator.APPLY_KEY_VALUE(state, keys[i]);
 			}
-			return state;
+			return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 		}
 		
 		@Override
-		public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+		public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 			Objects.requireNonNull(filter);
-			if(size() <= 0) return EMPTY_KEY_VALUE;
-			if(containsNull && filter.test(keys[nullIndex])) return keys[nullIndex];
+			if(size() <= 0) return OPTIONAL.empty();
+			if(containsNull && filter.test(keys[nullIndex])) return OPTIONAL.GET_OPTIONAL(keys[nullIndex]);
 			for(int i = nullIndex-1;i>=0;i--) {
-				if(KEY_EQUALS_NOT_NULL(keys[i]) && filter.test(keys[i])) return keys[i];
+				if(KEY_EQUALS_NOT_NULL(keys[i]) && filter.test(keys[i])) return OPTIONAL.GET_OPTIONAL(keys[i]);
 			}
-			return EMPTY_KEY_VALUE;
+			return OPTIONAL.empty();
 		}
 		
 		@Override
@ -1452,7 +1459,7 @@ public class HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_GENE
 		
 #endif
 		@Override
-		public VALUE_TYPE reduce(VALUE_SINGLE_UNARY_OPERATOR VALUE_VALUE_GENERIC_TYPE operator) {
+		public VALUE_OPTIONAL VALUE_GENERIC_TYPE reduce(VALUE_SINGLE_UNARY_OPERATOR VALUE_VALUE_GENERIC_TYPE operator) {
 			Objects.requireNonNull(operator);
 			VALUE_TYPE state = EMPTY_VALUE;
 			boolean empty = true;
@ -1469,18 +1476,18 @@ public class HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_GENE
 				}
 				state = operator.APPLY_VALUE(state, values[i]);
 			}
-			return state;
+			return empty ? VALUE_OPTIONAL.empty() : VALUE_OPTIONAL.GET_OPTIONAL_VALUE(state);
 		}
 		
 		@Override
-		public VALUE_TYPE findFirst(VALUE_PREDICATE VALUE_GENERIC_TYPE filter) {
+		public VALUE_OPTIONAL VALUE_GENERIC_TYPE findFirst(VALUE_PREDICATE VALUE_GENERIC_TYPE filter) {
 			Objects.requireNonNull(filter);
-			if(size() <= 0) return EMPTY_VALUE;
-			if(containsNull && filter.test(values[nullIndex])) return values[nullIndex];
+			if(size() <= 0) return VALUE_OPTIONAL.empty();
+			if(containsNull && filter.test(values[nullIndex])) return VALUE_OPTIONAL.GET_OPTIONAL_VALUE(values[nullIndex]);
 			for(int i = nullIndex-1;i>=0;i--) {
-				if(KEY_EQUALS_NOT_NULL(keys[i]) && filter.test(values[i])) return values[i];
+				if(KEY_EQUALS_NOT_NULL(keys[i]) && filter.test(values[i])) return VALUE_OPTIONAL.GET_OPTIONAL_VALUE(values[i]);
 			}
-			return EMPTY_VALUE;
+			return VALUE_OPTIONAL.empty();
 		}
 		
 		@Override
--- a/src/builder/resources/speiger/assets/collections/templates/maps/impl/immutable/ImmutableOpenHashMap.template
+++ b/src/builder/resources/speiger/assets/collections/templates/maps/impl/immutable/ImmutableOpenHashMap.template
@ -4,14 +4,17 @@ import java.util.Arrays;
 import java.util.Map;
 import java.util.NoSuchElementException;
 import java.util.Objects;
+import java.util.Optional;
 import java.util.function.Consumer;
 import java.util.function.BiFunction;
 import java.util.function.Predicate;
 #if !TYPE_OBJECT && JDK_TYPE
 import java.util.function.PREDICATE;
+import java.util.OPTIONAL;
 #endif
 #if !SAME_TYPE && JDK_VALUE && !VALUE_OBJECT
 import java.util.function.VALUE_PREDICATE;
+import java.util.VALUE_OPTIONAL;
 #endif

 #if !TYPE_OBJECT
@ -26,9 +29,12 @@ import speiger.src.collections.ints.functions.consumer.IntObjectConsumer;
 #if !SAME_TYPE && !TYPE_INT
 import speiger.src.collections.ints.functions.consumer.VALUE_BI_FROM_INT_CONSUMER;
 #endif
-#if !TYPE_OBJECT && !VALUE_BOOLEAN && !JDK_TYPE
+#if !TYPE_OBJECT && !JDK_TYPE
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#if !VALUE_BOOLEAN
 import speiger.src.collections.PACKAGE.functions.function.PREDICATE;
 #endif
+#endif
 #if !TYPE_INT || !SAME_TYPE
 import speiger.src.collections.PACKAGE.functions.consumer.BI_CONSUMER;
 #endif
@ -59,6 +65,7 @@ import speiger.src.collections.objects.functions.consumer.VALUE_BI_FROM_OBJECT_C
 #endif
 #if !JDK_VALUE
 import speiger.src.collections.VALUE_PACKAGE.functions.function.VALUE_PREDICATE;
+import speiger.src.collections.VALUE_PACKAGE.functions.VALUE_OPTIONAL;
 #endif
 #endif
 #if !TYPE_OBJECT
@ -783,7 +790,7 @@ public class IMMUTABLE_HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_
 		}
 		
 		@Override
-		public MAP.Entry KEY_VALUE_GENERIC_TYPE reduce(ObjectObjectUnaryOperator<MAP.Entry KEY_VALUE_GENERIC_TYPE, MAP.Entry KEY_VALUE_GENERIC_TYPE> operator) {
+		public Optional<MAP.Entry KEY_VALUE_GENERIC_TYPE> reduce(ObjectObjectUnaryOperator<MAP.Entry KEY_VALUE_GENERIC_TYPE, MAP.Entry KEY_VALUE_GENERIC_TYPE> operator) {
 			Objects.requireNonNull(operator);
 			MAP.Entry KEY_VALUE_GENERIC_TYPE state = null;
 			boolean empty = true;
@ -798,21 +805,21 @@ public class IMMUTABLE_HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_
 				state = operator.apply(state, new BasicEntryKV_BRACES(keys[index], values[index]));
 				index = (int)links[index];
 			}
-			return state;
+			return empty ? Optional.empty() : Optional.ofNullable(state);
 		}
 		
 		@Override
-		public MAP.Entry KEY_VALUE_GENERIC_TYPE findFirst(Predicate<MAP.Entry KEY_VALUE_GENERIC_TYPE> filter) {
+		public Optional<MAP.Entry KEY_VALUE_GENERIC_TYPE> findFirst(Predicate<MAP.Entry KEY_VALUE_GENERIC_TYPE> filter) {
 			Objects.requireNonNull(filter);
-			if(size() <= 0) return null;
+			if(size() <= 0) return Optional.empty();
 			BasicEntry KEY_VALUE_GENERIC_TYPE entry = new BasicEntryKV_BRACES();
 			int index = firstIndex;
 			while(index != -1) {
 				entry.set(keys[index], values[index]);
-				if(filter.test(entry)) return entry;
+				if(filter.test(entry)) return Optional.ofNullable(entry);
 				index = (int)links[index];
 			}
-			return null;
+			return Optional.empty();
 		}
 		
 		@Override
@ -1037,7 +1044,7 @@ public class IMMUTABLE_HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_
 		
 #endif
 		@Override
-		public KEY_TYPE reduce(SINGLE_UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+		public OPTIONAL KEY_GENERIC_TYPE reduce(SINGLE_UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 			Objects.requireNonNull(operator);
 			KEY_TYPE state = EMPTY_KEY_VALUE;
 			boolean empty = true;
@ -1052,19 +1059,19 @@ public class IMMUTABLE_HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_
 				state = operator.APPLY_KEY_VALUE(state, keys[index]);
 				index = (int)links[index];
 			}
-			return state;
+			return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 		}
 		
 		@Override
-		public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+		public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 			Objects.requireNonNull(filter);
-			if(size() <= 0) return EMPTY_KEY_VALUE;
+			if(size() <= 0) return OPTIONAL.empty();
 			int index = firstIndex;
 			while(index != -1){
-				if(filter.test(keys[index])) return keys[index];
+				if(filter.test(keys[index])) return OPTIONAL.GET_OPTIONAL(keys[index]);
 				index = (int)links[index];
 			}
-			return EMPTY_KEY_VALUE;
+			return OPTIONAL.empty();
 		}
 		
 		@Override
@ -1213,7 +1220,7 @@ public class IMMUTABLE_HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_
 		
 #endif
 		@Override
-		public VALUE_TYPE reduce(VALUE_SINGLE_UNARY_OPERATOR VALUE_VALUE_GENERIC_TYPE operator) {
+		public VALUE_OPTIONAL VALUE_GENERIC_TYPE reduce(VALUE_SINGLE_UNARY_OPERATOR VALUE_VALUE_GENERIC_TYPE operator) {
 			Objects.requireNonNull(operator);
 			VALUE_TYPE state = EMPTY_VALUE;
 			boolean empty = true;
@ -1228,19 +1235,19 @@ public class IMMUTABLE_HASH_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_
 				state = operator.APPLY_VALUE(state, values[index]);
 				index = (int)links[index];
 			}
-			return state;
+			return empty ? VALUE_OPTIONAL.empty() : VALUE_OPTIONAL.GET_OPTIONAL_VALUE(state);
 		}
 		
 		@Override
-		public VALUE_TYPE findFirst(VALUE_PREDICATE VALUE_GENERIC_TYPE filter) {
+		public VALUE_OPTIONAL VALUE_GENERIC_TYPE findFirst(VALUE_PREDICATE VALUE_GENERIC_TYPE filter) {
 			Objects.requireNonNull(filter);
-			if(size() <= 0) return EMPTY_VALUE;
+			if(size() <= 0) return VALUE_OPTIONAL.empty();
 			int index = firstIndex;
 			while(index != -1){
-				if(filter.test(values[index])) return values[index];
+				if(filter.test(values[index])) return VALUE_OPTIONAL.GET_OPTIONAL_VALUE(values[index]);
 				index = (int)links[index];
 			}
-			return EMPTY_VALUE;
+			return VALUE_OPTIONAL.empty();
 		}
 		
 		@Override
--- a/src/builder/resources/speiger/assets/collections/templates/maps/impl/misc/ArrayMap.template
+++ b/src/builder/resources/speiger/assets/collections/templates/maps/impl/misc/ArrayMap.template
@ -4,14 +4,17 @@ import java.util.Arrays;
 import java.util.Map;
 import java.util.NoSuchElementException;
 import java.util.Objects;
+import java.util.Optional;
 import java.util.function.Consumer;
 import java.util.function.BiFunction;
 import java.util.function.Predicate;
 #if !TYPE_OBJECT && JDK_TYPE
 import java.util.function.PREDICATE;
+import java.util.OPTIONAL;
 #endif
 #if !SAME_TYPE && JDK_VALUE && !VALUE_OBJECT
 import java.util.function.VALUE_PREDICATE;
+import java.util.VALUE_OPTIONAL;
 #endif

 import speiger.src.collections.PACKAGE.collections.BI_ITERATOR;
@ -26,9 +29,12 @@ import speiger.src.collections.ints.functions.consumer.IntObjectConsumer;
 #if !SAME_TYPE && !TYPE_INT
 import speiger.src.collections.ints.functions.consumer.VALUE_BI_FROM_INT_CONSUMER;
 #endif
-#if !TYPE_OBJECT && !VALUE_BOOLEAN && !JDK_TYPE
+#if !TYPE_OBJECT && !JDK_TYPE
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#if!VALUE_BOOLEAN
 import speiger.src.collections.PACKAGE.functions.function.PREDICATE;
 #endif
+#endif
 #if !TYPE_INT || !SAME_TYPE
 import speiger.src.collections.PACKAGE.functions.consumer.BI_CONSUMER;
 #endif
@ -66,6 +72,7 @@ import speiger.src.collections.objects.functions.consumer.VALUE_BI_FROM_OBJECT_C
 #endif
 #if !JDK_VALUE
 import speiger.src.collections.VALUE_PACKAGE.functions.function.VALUE_PREDICATE;
+import speiger.src.collections.VALUE_PACKAGE.functions.VALUE_OPTIONAL;
 #endif
 #endif
 #if !VALUE_OBJECT
@ -1009,7 +1016,7 @@ public class ARRAY_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_GEN
 		}
 		
 		@Override
-		public MAP.Entry KEY_VALUE_GENERIC_TYPE reduce(ObjectObjectUnaryOperator<MAP.Entry KEY_VALUE_GENERIC_TYPE, MAP.Entry KEY_VALUE_GENERIC_TYPE> operator) {
+		public Optional<MAP.Entry KEY_VALUE_GENERIC_TYPE> reduce(ObjectObjectUnaryOperator<MAP.Entry KEY_VALUE_GENERIC_TYPE, MAP.Entry KEY_VALUE_GENERIC_TYPE> operator) {
 			Objects.requireNonNull(operator);
 			MAP.Entry KEY_VALUE_GENERIC_TYPE state = null;
 			boolean empty = true;
@ -1021,19 +1028,19 @@ public class ARRAY_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_GEN
 				}
 				state = operator.apply(state, new ValueMapEntry(i));
 			}
-			return state;
+			return empty ? Optional.empty() : Optional.ofNullable(state);
 		}
 		
 		@Override
-		public MAP.Entry KEY_VALUE_GENERIC_TYPE findFirst(Predicate<MAP.Entry KEY_VALUE_GENERIC_TYPE> filter) {
+		public Optional<MAP.Entry KEY_VALUE_GENERIC_TYPE> findFirst(Predicate<MAP.Entry KEY_VALUE_GENERIC_TYPE> filter) {
 			Objects.requireNonNull(filter);
-			if(size() <= 0) return null;
+			if(size() <= 0) return Optional.empty();
 			MapEntry entry = new MapEntry();
 			for(int i = 0;i<size;i++) {
 				entry.set(i);
-				if(filter.test(entry)) return entry;
+				if(filter.test(entry)) return Optional.ofNullable(entry);
 			}
-			return null;
+			return Optional.empty();
 		}
 		
 		@Override
@ -1218,7 +1225,7 @@ public class ARRAY_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_GEN
 		
 #endif
 		@Override
-		public KEY_TYPE reduce(SINGLE_UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+		public OPTIONAL KEY_GENERIC_TYPE reduce(SINGLE_UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 			Objects.requireNonNull(operator);
 			KEY_TYPE state = EMPTY_KEY_VALUE;
 			boolean empty = true;
@ -1230,16 +1237,16 @@ public class ARRAY_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_GEN
 				}
 				state = operator.APPLY_KEY_VALUE(state, keys[i]);
 			}
-			return state;
+			return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 		}
 		
 		@Override
-		public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+		public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 			Objects.requireNonNull(filter);
 			for(int i = 0;i<size;i++) {
-				if(filter.test(keys[i])) return keys[i];
+				if(filter.test(keys[i])) return OPTIONAL.GET_OPTIONAL(keys[i]);
 			}
-			return EMPTY_KEY_VALUE;
+			return OPTIONAL.empty();
 		}
 		
 		@Override
@ -1359,7 +1366,7 @@ public class ARRAY_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_GEN
 		
 #endif
 		@Override
-		public VALUE_TYPE reduce(VALUE_SINGLE_UNARY_OPERATOR VALUE_VALUE_GENERIC_TYPE operator) {
+		public VALUE_OPTIONAL VALUE_GENERIC_TYPE reduce(VALUE_SINGLE_UNARY_OPERATOR VALUE_VALUE_GENERIC_TYPE operator) {
 			Objects.requireNonNull(operator);
 			VALUE_TYPE state = EMPTY_VALUE;
 			boolean empty = true;
@ -1371,16 +1378,16 @@ public class ARRAY_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_GEN
 				}
 				state = operator.APPLY_VALUE(state, values[i]);
 			}
-			return state;
+			return empty ? VALUE_OPTIONAL.empty() : VALUE_OPTIONAL.GET_OPTIONAL_VALUE(state);
 		}
 		
 		@Override
-		public VALUE_TYPE findFirst(VALUE_PREDICATE VALUE_GENERIC_TYPE filter) {
+		public VALUE_OPTIONAL VALUE_GENERIC_TYPE findFirst(VALUE_PREDICATE VALUE_GENERIC_TYPE filter) {
 			Objects.requireNonNull(filter);
 			for(int i = 0;i<size;i++) {
-				if(filter.test(values[i])) return values[i];
+				if(filter.test(values[i])) return VALUE_OPTIONAL.GET_OPTIONAL_VALUE(values[i]);
 			}
-			return EMPTY_VALUE;
+			return VALUE_OPTIONAL.empty();
 		}
 		
 		@Override
--- a/src/builder/resources/speiger/assets/collections/templates/maps/impl/tree/AVLTreeMap.template
+++ b/src/builder/resources/speiger/assets/collections/templates/maps/impl/tree/AVLTreeMap.template
@ -6,15 +6,18 @@ import java.util.Map;
 import java.util.Comparator;
 #endif
 import java.util.Objects;
+import java.util.Optional;
 import java.util.NoSuchElementException;
 import java.util.function.Consumer;
 import java.util.function.BiFunction;
 import java.util.function.Predicate;
 #if !TYPE_OBJECT && JDK_TYPE
 import java.util.function.PREDICATE;
+import java.util.OPTIONAL;
 #endif
 #if !SAME_TYPE && JDK_VALUE && !VALUE_OBJECT
 import java.util.function.VALUE_PREDICATE;
+import java.util.VALUE_OPTIONAL;
 #endif


@ -37,9 +40,12 @@ import speiger.src.collections.PACKAGE.functions.function.FUNCTION;
 #if !TYPE_INT || !SAME_TYPE
 import speiger.src.collections.PACKAGE.functions.consumer.BI_CONSUMER;
 #endif
-#if !TYPE_OBJECT && !VALUE_BOOLEAN && !JDK_TYPE
+#if !TYPE_OBJECT && !JDK_TYPE
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#if!VALUE_BOOLEAN
 import speiger.src.collections.PACKAGE.functions.function.PREDICATE;
 #endif
+#endif
 import speiger.src.collections.PACKAGE.functions.function.UNARY_OPERATOR;
 #if !SAME_TYPE
 import speiger.src.collections.PACKAGE.functions.function.SINGLE_UNARY_OPERATOR;
@ -73,6 +79,7 @@ import speiger.src.collections.objects.functions.consumer.VALUE_BI_FROM_OBJECT_C
 #endif
 #if !JDK_VALUE
 import speiger.src.collections.VALUE_PACKAGE.functions.function.VALUE_PREDICATE;
+import speiger.src.collections.VALUE_PACKAGE.functions.VALUE_OPTIONAL;
 #endif
 #endif
 #if !TYPE_OBJECT && !VALUE_OBJECT
@ -1323,7 +1330,7 @@ public class AVL_TREE_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_
 		
 #endif
 		@Override
-		public KEY_TYPE reduce(SINGLE_UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+		public OPTIONAL KEY_GENERIC_TYPE reduce(SINGLE_UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 			Objects.requireNonNull(operator);
 			KEY_TYPE state = EMPTY_KEY_VALUE;
 			boolean empty = true;
@ -1335,15 +1342,15 @@ public class AVL_TREE_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_
 				}
 				state = operator.APPLY_KEY_VALUE(state, entry.key);
 			}
-			return state;
+			return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 		}
 		
 		@Override
-		public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+		public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 			Objects.requireNonNull(filter);
 			for(Node KEY_VALUE_GENERIC_TYPE entry = start(), end = end();entry != null && (end == null || (end != previous(entry)));entry = next(entry))
-				if(filter.test(entry.key)) return entry.key;
-			return EMPTY_KEY_VALUE;
+				if(filter.test(entry.key)) return OPTIONAL.GET_OPTIONAL(entry.key);
+			return OPTIONAL.empty();
 		}
 		
 		@Override
@ -2026,7 +2033,7 @@ public class AVL_TREE_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_
 			}
 			
 			@Override
-			public MAP.Entry KEY_VALUE_GENERIC_TYPE reduce(ObjectObjectUnaryOperator<MAP.Entry KEY_VALUE_GENERIC_TYPE, MAP.Entry KEY_VALUE_GENERIC_TYPE> operator) {
+			public Optional<MAP.Entry KEY_VALUE_GENERIC_TYPE> reduce(ObjectObjectUnaryOperator<MAP.Entry KEY_VALUE_GENERIC_TYPE, MAP.Entry KEY_VALUE_GENERIC_TYPE> operator) {
 				Objects.requireNonNull(operator);
 				MAP.Entry KEY_VALUE_GENERIC_TYPE state = null;
 				boolean empty = true;
@ -2038,19 +2045,19 @@ public class AVL_TREE_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_
 					}
 					state = operator.apply(state, new BasicEntryKV_BRACES(entry.key, entry.value));
 				}
-				return state;
+				return empty ? Optional.empty() : Optional.ofNullable(state);
 			}
 			
 			@Override
-			public MAP.Entry KEY_VALUE_GENERIC_TYPE findFirst(Predicate<MAP.Entry KEY_VALUE_GENERIC_TYPE> filter) {
+			public Optional<MAP.Entry KEY_VALUE_GENERIC_TYPE> findFirst(Predicate<MAP.Entry KEY_VALUE_GENERIC_TYPE> filter) {
 				Objects.requireNonNull(filter);
-				if(size() <= 0) return null;
+				if(size() <= 0) return Optional.empty();
 				BasicEntry KEY_VALUE_GENERIC_TYPE subEntry = new BasicEntryKV_BRACES();
 				for(Node KEY_VALUE_GENERIC_TYPE entry = subLowest(), last = subHighest();entry != null && (last == null || last != previous(entry));entry = next(entry)) {
 					subEntry.set(entry.key, entry.value);
-					if(filter.test(subEntry)) return subEntry;
+					if(filter.test(subEntry)) return Optional.ofNullable(subEntry);
 				}
-				return null;
+				return Optional.empty();
 			}
 			
 			@Override
@ -2165,7 +2172,7 @@ public class AVL_TREE_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_
 			
 #endif
 			@Override
-			public VALUE_TYPE reduce(VALUE_SINGLE_UNARY_OPERATOR VALUE_VALUE_GENERIC_TYPE operator) {
+			public VALUE_OPTIONAL VALUE_GENERIC_TYPE reduce(VALUE_SINGLE_UNARY_OPERATOR VALUE_VALUE_GENERIC_TYPE operator) {
 				Objects.requireNonNull(operator);
 				VALUE_TYPE state = EMPTY_VALUE;
 				boolean empty = true;
@ -2177,15 +2184,15 @@ public class AVL_TREE_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_
 					}
 					state = operator.APPLY_VALUE(state, entry.value);
 				}
-				return state;
+				return empty ? VALUE_OPTIONAL.empty() : VALUE_OPTIONAL.GET_OPTIONAL_VALUE(state);
 			}
 			
 			@Override
-			public VALUE_TYPE findFirst(VALUE_PREDICATE VALUE_GENERIC_TYPE filter) {
+			public VALUE_OPTIONAL VALUE_GENERIC_TYPE findFirst(VALUE_PREDICATE VALUE_GENERIC_TYPE filter) {
 				Objects.requireNonNull(filter);
 				for(Node KEY_VALUE_GENERIC_TYPE entry = subLowest(), last = subHighest();entry != null && (last == null || last != previous(entry));entry = next(entry))
-					if(filter.test(entry.value)) return entry.value;
-				return EMPTY_VALUE;
+					if(filter.test(entry.value)) return VALUE_OPTIONAL.GET_OPTIONAL_VALUE(entry.value);
+				return VALUE_OPTIONAL.empty();
 			}
 			
 			@Override
@ -2521,7 +2528,7 @@ public class AVL_TREE_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_
 		
 		#endif
 		@Override
-		public VALUE_TYPE reduce(VALUE_SINGLE_UNARY_OPERATOR VALUE_VALUE_GENERIC_TYPE operator) {
+		public VALUE_OPTIONAL VALUE_GENERIC_TYPE reduce(VALUE_SINGLE_UNARY_OPERATOR VALUE_VALUE_GENERIC_TYPE operator) {
 			Objects.requireNonNull(operator);
 			VALUE_TYPE state = EMPTY_VALUE;
 			boolean empty = true;
@ -2533,15 +2540,15 @@ public class AVL_TREE_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_
 				}
 				state = operator.APPLY_VALUE(state, entry.value);
 			}
-			return state;
+			return empty ? VALUE_OPTIONAL.empty() : VALUE_OPTIONAL.GET_OPTIONAL_VALUE(state);
 		}
 		
 		@Override
-		public VALUE_TYPE findFirst(VALUE_PREDICATE VALUE_GENERIC_TYPE filter) {
+		public VALUE_OPTIONAL VALUE_GENERIC_TYPE findFirst(VALUE_PREDICATE VALUE_GENERIC_TYPE filter) {
 			Objects.requireNonNull(filter);
 			for(Node KEY_VALUE_GENERIC_TYPE entry = first;entry != null;entry = entry.next())
-				if(filter.test(entry.value)) return entry.value;
-			return EMPTY_VALUE;
+				if(filter.test(entry.value)) return VALUE_OPTIONAL.GET_OPTIONAL_VALUE(entry.value);
+			return VALUE_OPTIONAL.empty();
 		}
 		
 		@Override
@ -2687,7 +2694,7 @@ public class AVL_TREE_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_
 		}
 		
 		@Override
-		public MAP.Entry KEY_VALUE_GENERIC_TYPE reduce(ObjectObjectUnaryOperator<MAP.Entry KEY_VALUE_GENERIC_TYPE, MAP.Entry KEY_VALUE_GENERIC_TYPE> operator) {
+		public Optional<MAP.Entry KEY_VALUE_GENERIC_TYPE> reduce(ObjectObjectUnaryOperator<MAP.Entry KEY_VALUE_GENERIC_TYPE, MAP.Entry KEY_VALUE_GENERIC_TYPE> operator) {
 			Objects.requireNonNull(operator);
 			MAP.Entry KEY_VALUE_GENERIC_TYPE state = null;
 			boolean empty = true;
@ -2699,19 +2706,19 @@ public class AVL_TREE_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_
 				}
 				state = operator.apply(state, new BasicEntryKV_BRACES(entry.key, entry.value));
 			}
-			return state;
+			return empty ? Optional.empty() : Optional.ofNullable(state);
 		}
 		
 		@Override
-		public MAP.Entry KEY_VALUE_GENERIC_TYPE findFirst(Predicate<MAP.Entry KEY_VALUE_GENERIC_TYPE> filter) {
+		public Optional<MAP.Entry KEY_VALUE_GENERIC_TYPE> findFirst(Predicate<MAP.Entry KEY_VALUE_GENERIC_TYPE> filter) {
 			Objects.requireNonNull(filter);
-			if(size() <= 0) return null;
+			if(size() <= 0) return Optional.empty();
 			BasicEntry KEY_VALUE_GENERIC_TYPE subEntry = new BasicEntryKV_BRACES();
 			for(Node KEY_VALUE_GENERIC_TYPE entry = first;entry != null;entry = entry.next()) {
 				subEntry.set(entry.key, entry.value);
-				if(filter.test(subEntry)) return subEntry;
+				if(filter.test(subEntry)) return Optional.ofNullable(subEntry);
 			}
-			return null;
+			return Optional.empty();
 		}
 		
 		@Override
--- a/src/builder/resources/speiger/assets/collections/templates/maps/impl/tree/RBTreeMap.template
+++ b/src/builder/resources/speiger/assets/collections/templates/maps/impl/tree/RBTreeMap.template
@ -6,15 +6,18 @@ import java.util.Map;
 import java.util.Comparator;
 #endif
 import java.util.Objects;
+import java.util.Optional;
 import java.util.NoSuchElementException;
 import java.util.function.Consumer;
 import java.util.function.BiFunction;
 import java.util.function.Predicate;
 #if !TYPE_OBJECT && JDK_TYPE
 import java.util.function.PREDICATE;
+import java.util.OPTIONAL;
 #endif
 #if !SAME_TYPE && JDK_VALUE && !VALUE_OBJECT
 import java.util.function.VALUE_PREDICATE;
+import java.util.VALUE_OPTIONAL;
 #endif

 import speiger.src.collections.PACKAGE.collections.BI_ITERATOR;
@ -36,9 +39,12 @@ import speiger.src.collections.PACKAGE.functions.function.FUNCTION;
 #if !TYPE_INT || !SAME_TYPE
 import speiger.src.collections.PACKAGE.functions.consumer.BI_CONSUMER;
 #endif
-#if !TYPE_OBJECT && !VALUE_BOOLEAN && !JDK_TYPE
+#if !TYPE_OBJECT && !JDK_TYPE
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#if!VALUE_BOOLEAN
 import speiger.src.collections.PACKAGE.functions.function.PREDICATE;
 #endif
+#endif
 import speiger.src.collections.PACKAGE.functions.function.UNARY_OPERATOR;
 #if !SAME_TYPE
 import speiger.src.collections.PACKAGE.functions.function.SINGLE_UNARY_OPERATOR;
@ -72,6 +78,7 @@ import speiger.src.collections.objects.functions.consumer.VALUE_BI_FROM_OBJECT_C
 #endif
 #if !JDK_VALUE
 import speiger.src.collections.VALUE_PACKAGE.functions.function.VALUE_PREDICATE;
+import speiger.src.collections.VALUE_PACKAGE.functions.VALUE_OPTIONAL;
 #endif
 #endif
 #if !TYPE_OBJECT && !VALUE_OBJECT
@ -1379,7 +1386,7 @@ public class RB_TREE_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_G
 		
 #endif
 		@Override
-		public KEY_TYPE reduce(SINGLE_UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+		public OPTIONAL KEY_GENERIC_TYPE reduce(SINGLE_UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 			Objects.requireNonNull(operator);
 			KEY_TYPE state = EMPTY_KEY_VALUE;
 			boolean empty = true;
@ -1391,15 +1398,15 @@ public class RB_TREE_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_G
 				}
 				state = operator.APPLY_KEY_VALUE(state, entry.key);
 			}
-			return state;
+			return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 		}
 		
 		@Override
-		public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+		public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 			Objects.requireNonNull(filter);
 			for(Node KEY_VALUE_GENERIC_TYPE entry = start(), end = end();entry != null && (end == null || (end != previous(entry)));entry = next(entry))
-				if(filter.test(entry.key)) return entry.key;
-			return EMPTY_KEY_VALUE;
+				if(filter.test(entry.key)) return OPTIONAL.GET_OPTIONAL(entry.key);
+			return OPTIONAL.empty();
 		}
 		
 		@Override
@ -2092,7 +2099,7 @@ public class RB_TREE_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_G
 			}
 			
 			@Override
-			public MAP.Entry KEY_VALUE_GENERIC_TYPE reduce(ObjectObjectUnaryOperator<MAP.Entry KEY_VALUE_GENERIC_TYPE, MAP.Entry KEY_VALUE_GENERIC_TYPE> operator) {
+			public Optional<MAP.Entry KEY_VALUE_GENERIC_TYPE> reduce(ObjectObjectUnaryOperator<MAP.Entry KEY_VALUE_GENERIC_TYPE, MAP.Entry KEY_VALUE_GENERIC_TYPE> operator) {
 				Objects.requireNonNull(operator);
 				MAP.Entry KEY_VALUE_GENERIC_TYPE state = null;
 				boolean empty = true;
@ -2104,19 +2111,19 @@ public class RB_TREE_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_G
 					}
 					state = operator.apply(state, new BasicEntryKV_BRACES(entry.key, entry.value));
 				}
-				return state;
+				return empty ? Optional.empty() : Optional.ofNullable(state);
 			}
 			
 			@Override
-			public MAP.Entry KEY_VALUE_GENERIC_TYPE findFirst(Predicate<MAP.Entry KEY_VALUE_GENERIC_TYPE> filter) {
+			public Optional<MAP.Entry KEY_VALUE_GENERIC_TYPE> findFirst(Predicate<MAP.Entry KEY_VALUE_GENERIC_TYPE> filter) {
 				Objects.requireNonNull(filter);
-				if(size() <= 0) return null;
+				if(size() <= 0) return Optional.empty();
 				BasicEntry KEY_VALUE_GENERIC_TYPE subEntry = new BasicEntryKV_BRACES();
 				for(Node KEY_VALUE_GENERIC_TYPE entry = subLowest(), last = subHighest();entry != null && (last == null || last != previous(entry));entry = next(entry)) {
 					subEntry.set(entry.key, entry.value);
-					if(filter.test(subEntry)) return subEntry;
+					if(filter.test(subEntry)) return Optional.ofNullable(subEntry);
 				}
-				return null;
+				return Optional.empty();
 			}
 			
 			@Override
@ -2231,7 +2238,7 @@ public class RB_TREE_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_G
 			
 #endif
 			@Override
-			public VALUE_TYPE reduce(VALUE_SINGLE_UNARY_OPERATOR VALUE_VALUE_GENERIC_TYPE operator) {
+			public VALUE_OPTIONAL VALUE_GENERIC_TYPE reduce(VALUE_SINGLE_UNARY_OPERATOR VALUE_VALUE_GENERIC_TYPE operator) {
 				Objects.requireNonNull(operator);
 				VALUE_TYPE state = EMPTY_VALUE;
 				boolean empty = true;
@ -2243,15 +2250,15 @@ public class RB_TREE_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_G
 					}
 					state = operator.APPLY_VALUE(state, entry.value);
 				}
-				return state;
+				return empty ? VALUE_OPTIONAL.empty() : VALUE_OPTIONAL.GET_OPTIONAL_VALUE(state);
 			}
 			
 			@Override
-			public VALUE_TYPE findFirst(VALUE_PREDICATE VALUE_GENERIC_TYPE filter) {
+			public VALUE_OPTIONAL VALUE_GENERIC_TYPE findFirst(VALUE_PREDICATE VALUE_GENERIC_TYPE filter) {
 				Objects.requireNonNull(filter);
 				for(Node KEY_VALUE_GENERIC_TYPE entry = subLowest(), last = subHighest();entry != null && (last == null || last != previous(entry));entry = next(entry))
-					if(filter.test(entry.value)) return entry.value;
-				return EMPTY_VALUE;
+					if(filter.test(entry.value)) return VALUE_OPTIONAL.GET_OPTIONAL_VALUE(entry.value);
+				return VALUE_OPTIONAL.empty();
 			}
 			
 			@Override
@ -2587,7 +2594,7 @@ public class RB_TREE_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_G
 		
 		#endif
 		@Override
-		public VALUE_TYPE reduce(VALUE_SINGLE_UNARY_OPERATOR VALUE_VALUE_GENERIC_TYPE operator) {
+		public VALUE_OPTIONAL VALUE_GENERIC_TYPE reduce(VALUE_SINGLE_UNARY_OPERATOR VALUE_VALUE_GENERIC_TYPE operator) {
 			Objects.requireNonNull(operator);
 			VALUE_TYPE state = EMPTY_VALUE;
 			boolean empty = true;
@ -2599,15 +2606,15 @@ public class RB_TREE_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_G
 				}
 				state = operator.APPLY_VALUE(state, entry.value);
 			}
-			return state;
+			return empty ? VALUE_OPTIONAL.empty() : VALUE_OPTIONAL.GET_OPTIONAL_VALUE(state);
 		}
 		
 		@Override
-		public VALUE_TYPE findFirst(VALUE_PREDICATE VALUE_GENERIC_TYPE filter) {
+		public VALUE_OPTIONAL VALUE_GENERIC_TYPE findFirst(VALUE_PREDICATE VALUE_GENERIC_TYPE filter) {
 			Objects.requireNonNull(filter);
 			for(Node KEY_VALUE_GENERIC_TYPE entry = first;entry != null;entry = entry.next())
-				if(filter.test(entry.value)) return entry.value;
-			return EMPTY_VALUE;
+				if(filter.test(entry.value)) return VALUE_OPTIONAL.GET_OPTIONAL_VALUE(entry.value);
+			return VALUE_OPTIONAL.empty();
 		}
 		
 		@Override
@ -2753,7 +2760,7 @@ public class RB_TREE_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_G
 		}
 		
 		@Override
-		public MAP.Entry KEY_VALUE_GENERIC_TYPE reduce(ObjectObjectUnaryOperator<MAP.Entry KEY_VALUE_GENERIC_TYPE, MAP.Entry KEY_VALUE_GENERIC_TYPE> operator) {
+		public Optional<MAP.Entry KEY_VALUE_GENERIC_TYPE> reduce(ObjectObjectUnaryOperator<MAP.Entry KEY_VALUE_GENERIC_TYPE, MAP.Entry KEY_VALUE_GENERIC_TYPE> operator) {
 			Objects.requireNonNull(operator);
 			MAP.Entry KEY_VALUE_GENERIC_TYPE state = null;
 			boolean empty = true;
@ -2765,19 +2772,19 @@ public class RB_TREE_MAP KEY_VALUE_GENERIC_TYPE extends ABSTRACT_MAP KEY_VALUE_G
 				}
 				state = operator.apply(state, new BasicEntryKV_BRACES(entry.key, entry.value));
 			}
-			return state;
+			return empty ? Optional.empty() : Optional.ofNullable(state);
 		}
 		
 		@Override
-		public MAP.Entry KEY_VALUE_GENERIC_TYPE findFirst(Predicate<MAP.Entry KEY_VALUE_GENERIC_TYPE> filter) {
+		public Optional<MAP.Entry KEY_VALUE_GENERIC_TYPE> findFirst(Predicate<MAP.Entry KEY_VALUE_GENERIC_TYPE> filter) {
 			Objects.requireNonNull(filter);
-			if(size() <= 0) return null;
+			if(size() <= 0) return Optional.empty();
 			BasicEntry KEY_VALUE_GENERIC_TYPE subEntry = new BasicEntryKV_BRACES();
 			for(Node KEY_VALUE_GENERIC_TYPE entry = first;entry != null;entry = entry.next()) {
 				subEntry.set(entry.key, entry.value);
-				if(filter.test(subEntry)) return subEntry;
+				if(filter.test(subEntry)) return Optional.ofNullable(subEntry);
 			}
-			return null;
+			return Optional.empty();
 		}
 		
 		@Override
--- a/src/builder/resources/speiger/assets/collections/templates/queues/ArrayFIFOQueue.template
+++ b/src/builder/resources/speiger/assets/collections/templates/queues/ArrayFIFOQueue.template
@ -7,12 +7,18 @@ import java.util.function.Consumer;
 import java.util.function.BiFunction;
 #endif
 import java.util.Objects;
+#if JDK_TYPE
+import java.util.OPTIONAL;
+#endif
 import java.util.NoSuchElementException;
 #if JDK_FUNCTION
 import java.util.function.PREDICATE;
 #endif

 import speiger.src.collections.PACKAGE.collections.ITERATOR;
+#if !JDK_TYPE 
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#endif
 #if !TYPE_OBJECT
 import speiger.src.collections.PACKAGE.functions.COMPARATOR;
 import speiger.src.collections.PACKAGE.functions.CONSUMER;
@ -318,17 +324,17 @@ public class ARRAY_FIFO_QUEUE KEY_GENERIC_TYPE extends ABSTRACT_PRIORITY_QUEUE K
 	}
 	
 	@Override
-	public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+	public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 		Objects.requireNonNull(filter);
 		for(int i = 0,m=size();i<m;i++) {
 			int index = (first + i) % array.length;
 			if(filter.test(array[index])) {
 				KEY_TYPE data = array[index];
 				removeIndex(index);
-				return data;
+				return OPTIONAL.GET_OPTIONAL(data);
 			}
 		}
-		return EMPTY_VALUE;
+		return OPTIONAL.empty();
 	}
 	
 #if !TYPE_OBJECT
@ -355,7 +361,7 @@ public class ARRAY_FIFO_QUEUE KEY_GENERIC_TYPE extends ABSTRACT_PRIORITY_QUEUE K
 	
 #endif
 	@Override
-	public KEY_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+	public OPTIONAL KEY_GENERIC_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 		Objects.requireNonNull(operator);
 		KEY_TYPE state = EMPTY_VALUE;
 		boolean empty = true;
@ -367,7 +373,7 @@ public class ARRAY_FIFO_QUEUE KEY_GENERIC_TYPE extends ABSTRACT_PRIORITY_QUEUE K
 			}
 			state = operator.APPLY_VALUE(state, array[(first + i) % array.length]);
 		}
-		return state;
+		return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 	}
 	
 	@Override
--- a/src/builder/resources/speiger/assets/collections/templates/queues/ArrayPriorityQueue.template
+++ b/src/builder/resources/speiger/assets/collections/templates/queues/ArrayPriorityQueue.template
@ -8,12 +8,18 @@ import java.util.function.Consumer;
 import java.util.function.BiFunction;
 #endif
 import java.util.Objects;
+#if JDK_TYPE
+import java.util.OPTIONAL;
+#endif
 #if JDK_FUNCTION
 import java.util.function.PREDICATE;
 #endif

 import speiger.src.collections.PACKAGE.collections.COLLECTION;
 import speiger.src.collections.PACKAGE.collections.ITERATOR;
+#if !JDK_TYPE 
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#endif
 #if !TYPE_OBJECT
 import speiger.src.collections.PACKAGE.functions.COMPARATOR;
 import speiger.src.collections.PACKAGE.functions.CONSUMER;
@ -346,7 +352,7 @@ public class ARRAY_PRIORITY_QUEUE KEY_GENERIC_TYPE extends ABSTRACT_PRIORITY_QUE
 	
 #endif
 	@Override
-	public KEY_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+	public OPTIONAL KEY_GENERIC_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 		Objects.requireNonNull(operator);
 		KEY_TYPE state = EMPTY_VALUE;
 		boolean empty = true;
@ -358,20 +364,20 @@ public class ARRAY_PRIORITY_QUEUE KEY_GENERIC_TYPE extends ABSTRACT_PRIORITY_QUE
 			}
 			state = operator.APPLY_VALUE(state, array[i]);
 		}
-		return state;
+		return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 	}
 	
 	@Override
-	public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+	public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 		Objects.requireNonNull(filter);
 		for(int i = 0;i<size;i++) {
 			if(filter.test(array[i])) {
 				KEY_TYPE data = array[i];
 				removeIndex(i);
-				return data;
+				return OPTIONAL.GET_OPTIONAL(data);
 			}
 		}
-		return EMPTY_VALUE;
+		return OPTIONAL.empty();
 	}
 	
 	@Override
--- a/src/builder/resources/speiger/assets/collections/templates/queues/HeapPriorityQueue.template
+++ b/src/builder/resources/speiger/assets/collections/templates/queues/HeapPriorityQueue.template
@ -8,12 +8,18 @@ import java.util.function.Consumer;
 import java.util.function.BiFunction;
 #endif
 import java.util.Objects;
+#if JDK_TYPE
+import java.util.OPTIONAL;
+#endif
 #if JDK_FUNCTION
 import java.util.function.PREDICATE;
 #endif

 import speiger.src.collections.PACKAGE.collections.COLLECTION;
 import speiger.src.collections.PACKAGE.collections.ITERATOR;
+#if !JDK_TYPE 
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#endif
 #if !TYPE_OBJECT
 import speiger.src.collections.PACKAGE.functions.COMPARATOR;
 import speiger.src.collections.PACKAGE.functions.CONSUMER;
@ -326,7 +332,7 @@ public class HEAP_PRIORITY_QUEUE KEY_GENERIC_TYPE extends ABSTRACT_PRIORITY_QUEU
 	
 #endif
 	@Override
-	public KEY_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+	public OPTIONAL KEY_GENERIC_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 		Objects.requireNonNull(operator);
 		KEY_TYPE state = EMPTY_VALUE;
 		boolean empty = true;
@ -338,20 +344,20 @@ public class HEAP_PRIORITY_QUEUE KEY_GENERIC_TYPE extends ABSTRACT_PRIORITY_QUEU
 			}
 			state = operator.APPLY_VALUE(state, array[i]);
 		}
-		return state;
+		return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 	}
 	
 	@Override
-	public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+	public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 		Objects.requireNonNull(filter);
 		for(int i = 0;i<size;i++) {
 			if(filter.test(array[i])) {
 				KEY_TYPE data = array[i];
 				removeIndex(i);
-				return data;
+				return OPTIONAL.GET_OPTIONAL(data);
 			}
 		}
-		return EMPTY_VALUE;
+		return OPTIONAL.empty();
 	}
 	
 	@Override
--- a/src/builder/resources/speiger/assets/collections/templates/sets/AVLTreeSet.template
+++ b/src/builder/resources/speiger/assets/collections/templates/sets/AVLTreeSet.template
@ -10,6 +10,9 @@ import java.util.function.BiFunction;
 import java.util.Iterator;
 import java.util.NoSuchElementException;
 import java.util.Objects;
+#if JDK_TYPE
+import java.util.OPTIONAL;
+#endif
 #if JDK_FUNCTION
 import java.util.function.PREDICATE;
 #endif
@ -19,6 +22,9 @@ import speiger.src.collections.PACKAGE.collections.BI_ITERATOR;
 import speiger.src.collections.PACKAGE.functions.COMPARATOR;
 import speiger.src.collections.PACKAGE.functions.CONSUMER;
 #endif
+#if !JDK_TYPE 
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#endif
 import speiger.src.collections.ints.functions.consumer.BI_FROM_INT_CONSUMER;
 import speiger.src.collections.objects.functions.consumer.BI_FROM_OBJECT_CONSUMER;
 #if !JDK_FUNCTION
@ -405,12 +411,12 @@ public class AVL_TREE_SET KEY_GENERIC_TYPE extends ABSTRACT_SET KEY_GENERIC_TYPE
 	}
 	
 	@Override
-	public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+	public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 		Objects.requireNonNull(filter);
 		for(Entry KEY_GENERIC_TYPE entry = first;entry != null;entry = entry.next()) {
-			if(filter.test(entry.key)) return entry.key;
+			if(filter.test(entry.key)) return OPTIONAL.GET_OPTIONAL(entry.key);
 		}
-		return EMPTY_VALUE;
+		return OPTIONAL.empty();
 	}
 	
 #if !TYPE_OBJECT
@ -437,7 +443,7 @@ public class AVL_TREE_SET KEY_GENERIC_TYPE extends ABSTRACT_SET KEY_GENERIC_TYPE
 	
 #endif
 	@Override
-	public KEY_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+	public OPTIONAL KEY_GENERIC_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 		Objects.requireNonNull(operator);
 		KEY_TYPE state = EMPTY_VALUE;
 		boolean empty = true;
@ -449,7 +455,7 @@ public class AVL_TREE_SET KEY_GENERIC_TYPE extends ABSTRACT_SET KEY_GENERIC_TYPE
 			}
 			state = operator.APPLY_VALUE(state, entry.key);
 		}
-		return state;
+		return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 	}
 	
 	@Override
@ -1314,7 +1320,7 @@ public class AVL_TREE_SET KEY_GENERIC_TYPE extends ABSTRACT_SET KEY_GENERIC_TYPE
 		
 #endif
 		@Override
-		public KEY_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+		public OPTIONAL KEY_GENERIC_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 			Objects.requireNonNull(operator);
 			KEY_TYPE state = EMPTY_VALUE;
 			boolean empty = true;
@ -1326,16 +1332,16 @@ public class AVL_TREE_SET KEY_GENERIC_TYPE extends ABSTRACT_SET KEY_GENERIC_TYPE
 				}
 				state = operator.APPLY_VALUE(state, entry.key);
 			}
-			return state;
+			return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 		}
 		
 		@Override
-		public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+		public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 			Objects.requireNonNull(filter);
 			for(Entry KEY_GENERIC_TYPE entry = start();entry != null && inRange(entry.key);entry = next(entry)) {
-				if(filter.test(entry.key)) return entry.key;
+				if(filter.test(entry.key)) return OPTIONAL.GET_OPTIONAL(entry.key);
 			}
-			return EMPTY_VALUE;
+			return OPTIONAL.empty();
 		}
 		
 		@Override
--- a/src/builder/resources/speiger/assets/collections/templates/sets/ArraySet.template
+++ b/src/builder/resources/speiger/assets/collections/templates/sets/ArraySet.template
@ -8,6 +8,9 @@ import java.util.function.BiFunction;
 #endif
 import java.util.NoSuchElementException;
 import java.util.Objects;
+#if JDK_TYPE
+import java.util.OPTIONAL;
+#endif
 import java.util.Set;
 #if JDK_FUNCTION
 import java.util.function.PREDICATE;
@ -18,7 +21,9 @@ import java.util.function.JAVA_PREDICATE;
 import speiger.src.collections.PACKAGE.collections.BI_ITERATOR;
 import speiger.src.collections.PACKAGE.collections.COLLECTION;
 import speiger.src.collections.PACKAGE.collections.ITERATOR;
-
+#if !JDK_TYPE 
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#endif
 import speiger.src.collections.ints.functions.consumer.BI_FROM_INT_CONSUMER;
 import speiger.src.collections.objects.functions.consumer.BI_FROM_OBJECT_CONSUMER;
 #if !JDK_FUNCTION
@ -438,12 +443,12 @@ public class ARRAY_SET KEY_GENERIC_TYPE extends ABSTRACT_SET KEY_GENERIC_TYPE im
 	}
 	
 	@Override
-	public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+	public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 		Objects.requireNonNull(filter);
 		for(int i = 0;i<size;i++) {
-			if(filter.test(data[i])) return data[i];
+			if(filter.test(data[i])) return OPTIONAL.GET_OPTIONAL(data[i]);
 		}
-		return EMPTY_VALUE;
+		return OPTIONAL.empty();
 	}
 	
 #if !TYPE_OBJECT
@ -470,7 +475,7 @@ public class ARRAY_SET KEY_GENERIC_TYPE extends ABSTRACT_SET KEY_GENERIC_TYPE im
 	
 #endif
 	@Override
-	public KEY_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+	public OPTIONAL KEY_GENERIC_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 		Objects.requireNonNull(operator);
 		KEY_TYPE state = EMPTY_VALUE;
 		boolean empty = true;
@ -482,7 +487,7 @@ public class ARRAY_SET KEY_GENERIC_TYPE extends ABSTRACT_SET KEY_GENERIC_TYPE im
 			}
 			state = operator.APPLY_VALUE(state, data[i]);
 		}
-		return state;
+		return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 	}
 	
 	@Override
--- a/src/builder/resources/speiger/assets/collections/templates/sets/ImmutableOpenHashSet.template
+++ b/src/builder/resources/speiger/assets/collections/templates/sets/ImmutableOpenHashSet.template
@ -9,6 +9,9 @@ import java.util.Collection;
 import java.util.Iterator;
 import java.util.NoSuchElementException;
 import java.util.Objects;
+#if JDK_TYPE
+import java.util.OPTIONAL;
+#endif
 #if JDK_FUNCTION
 import java.util.function.PREDICATE;
 #endif
@ -19,6 +22,9 @@ import speiger.src.collections.PACKAGE.collections.ITERATOR;
 #if !TYPE_OBJECT
 import speiger.src.collections.PACKAGE.functions.CONSUMER;
 #endif
+#if !JDK_TYPE 
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#endif
 import speiger.src.collections.ints.functions.consumer.BI_FROM_INT_CONSUMER;
 import speiger.src.collections.objects.functions.consumer.BI_FROM_OBJECT_CONSUMER;
 #if !JDK_FUNCTION
@ -414,7 +420,7 @@ public class IMMUTABLE_HASH_SET KEY_GENERIC_TYPE extends ABSTRACT_SET KEY_GENERI
 	
 #endif
 	@Override
-	public KEY_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+	public OPTIONAL KEY_GENERIC_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 		Objects.requireNonNull(operator);
 		KEY_TYPE state = EMPTY_VALUE;
 		boolean empty = true;
@ -427,18 +433,18 @@ public class IMMUTABLE_HASH_SET KEY_GENERIC_TYPE extends ABSTRACT_SET KEY_GENERI
 			else state = operator.APPLY_VALUE(state, keys[index]);
 			index = (int)links[index];
 		}
-		return state;
+		return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 	}
 	
 	@Override
-	public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+	public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 		Objects.requireNonNull(filter);
 		int index = firstIndex;
 		while(index != -1) {
-			if(filter.test(keys[index])) return keys[index];
+			if(filter.test(keys[index])) return OPTIONAL.GET_OPTIONAL(keys[index]);
 			index = (int)links[index];
 		}
-		return EMPTY_VALUE;
+		return OPTIONAL.empty();
 	}
 	
 	@Override
--- a/src/builder/resources/speiger/assets/collections/templates/sets/LinkedOpenCustomHashSet.template
+++ b/src/builder/resources/speiger/assets/collections/templates/sets/LinkedOpenCustomHashSet.template
@ -9,6 +9,9 @@ import java.util.Objects;
 import java.util.Collection;
 import java.util.Iterator;
 import java.util.NoSuchElementException;
+#if JDK_TYPE
+import java.util.OPTIONAL;
+#endif
 #if JDK_FUNCTION
 import java.util.function.PREDICATE;
 #endif
@ -18,6 +21,9 @@ import speiger.src.collections.PACKAGE.collections.COLLECTION;
 import speiger.src.collections.PACKAGE.collections.ITERATOR;
 #endif
 import speiger.src.collections.PACKAGE.collections.BI_ITERATOR;
+#if !JDK_TYPE 
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#endif
 import speiger.src.collections.PACKAGE.lists.LIST_ITERATOR;
 #if !TYPE_OBJECT
 import speiger.src.collections.PACKAGE.utils.ITERATORS;
@ -656,7 +662,7 @@ public class LINKED_CUSTOM_HASH_SET KEY_GENERIC_TYPE extends CUSTOM_HASH_SET KEY
 	
 #endif
 	@Override
-	public KEY_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+	public OPTIONAL KEY_GENERIC_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 		Objects.requireNonNull(operator);
 		KEY_TYPE state = EMPTY_VALUE;
 		boolean empty = true;
@ -669,18 +675,18 @@ public class LINKED_CUSTOM_HASH_SET KEY_GENERIC_TYPE extends CUSTOM_HASH_SET KEY
 			else state = operator.APPLY_VALUE(state, keys[index]);
 			index = (int)links[index];
 		}
-		return state;
+		return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 	}
 	
 	@Override
-	public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+	public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 		Objects.requireNonNull(filter);
 		int index = firstIndex;
 		while(index != -1) {
-			if(filter.test(keys[index])) return keys[index];
+			if(filter.test(keys[index])) return OPTIONAL.GET_OPTIONAL(keys[index]);
 			index = (int)links[index];
 		}
-		return EMPTY_VALUE;
+		return OPTIONAL.empty();
 	}
 	
 	@Override
--- a/src/builder/resources/speiger/assets/collections/templates/sets/LinkedOpenHashSet.template
+++ b/src/builder/resources/speiger/assets/collections/templates/sets/LinkedOpenHashSet.template
@ -5,6 +5,9 @@ import java.util.Collection;
 import java.util.Iterator;
 import java.util.NoSuchElementException;
 import java.util.Objects;
+#if JDK_TYPE
+import java.util.OPTIONAL;
+#endif
 #if TYPE_OBJECT
 import java.util.function.Consumer;
 import java.util.function.BiFunction;
@ -21,6 +24,9 @@ import speiger.src.collections.PACKAGE.collections.BI_ITERATOR;
 #if !TYPE_OBJECT
 import speiger.src.collections.PACKAGE.functions.CONSUMER;
 #endif
+#if !JDK_TYPE 
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#endif
 import speiger.src.collections.ints.functions.consumer.BI_FROM_INT_CONSUMER;
 import speiger.src.collections.objects.functions.consumer.BI_FROM_OBJECT_CONSUMER;
 #if !JDK_FUNCTION
@ -511,7 +517,7 @@ public class LINKED_HASH_SET KEY_GENERIC_TYPE extends HASH_SET KEY_GENERIC_TYPE
 	
 #endif
 	@Override
-	public KEY_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+	public OPTIONAL KEY_GENERIC_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 		Objects.requireNonNull(operator);
 		KEY_TYPE state = EMPTY_VALUE;
 		boolean empty = true;
@ -524,18 +530,18 @@ public class LINKED_HASH_SET KEY_GENERIC_TYPE extends HASH_SET KEY_GENERIC_TYPE
 			else state = operator.APPLY_VALUE(state, keys[index]);
 			index = (int)links[index];
 		}
-		return state;
+		return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 	}
 	
 	@Override
-	public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+	public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 		Objects.requireNonNull(filter);
 		int index = firstIndex;
 		while(index != -1) {
-			if(filter.test(keys[index])) return keys[index];
+			if(filter.test(keys[index])) return OPTIONAL.GET_OPTIONAL(keys[index]);
 			index = (int)links[index];
 		}
-		return EMPTY_VALUE;
+		return OPTIONAL.empty();
 	}
 	
 	@Override
--- a/src/builder/resources/speiger/assets/collections/templates/sets/OpenCustomHashSet.template
+++ b/src/builder/resources/speiger/assets/collections/templates/sets/OpenCustomHashSet.template
@ -6,6 +6,9 @@ import java.util.ConcurrentModificationException;
 import java.util.Iterator;
 import java.util.NoSuchElementException;
 import java.util.Objects;
+#if JDK_TYPE
+import java.util.OPTIONAL;
+#endif
 #if TYPE_OBJECT
 import java.util.function.Consumer;
 import java.util.function.BiFunction;
@ -16,6 +19,9 @@ import java.util.function.PREDICATE;

 import speiger.src.collections.PACKAGE.collections.COLLECTION;
 import speiger.src.collections.PACKAGE.collections.ITERATOR;
+#if !JDK_TYPE 
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#endif
 #if !TYPE_OBJECT
 import speiger.src.collections.PACKAGE.utils.ITERATORS;
 import speiger.src.collections.PACKAGE.functions.CONSUMER;
@ -635,7 +641,7 @@ public class CUSTOM_HASH_SET KEY_GENERIC_TYPE extends ABSTRACT_SET KEY_GENERIC_T
 	
 #endif
 	@Override
-	public KEY_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+	public OPTIONAL KEY_GENERIC_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 		Objects.requireNonNull(operator);
 		KEY_TYPE state = EMPTY_VALUE;
 		boolean empty = true;
@ -652,18 +658,18 @@ public class CUSTOM_HASH_SET KEY_GENERIC_TYPE extends ABSTRACT_SET KEY_GENERIC_T
 			}
 			state = operator.APPLY_VALUE(state, keys[i]);
 		}
-		return state;
+		return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 	}
 	
 	@Override
-	public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+	public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 		Objects.requireNonNull(filter);
-		if(size() <= 0) return EMPTY_VALUE;
-		if(containsNull && filter.test(keys[nullIndex])) return keys[nullIndex];
+		if(size() <= 0) return OPTIONAL.empty();
+		if(containsNull && filter.test(keys[nullIndex])) return OPTIONAL.GET_OPTIONAL(keys[nullIndex]);
 		for(int i = nullIndex-1;i>=0;i--) {
-			if(!strategy.equals(keys[i], EMPTY_KEY_VALUE) && filter.test(keys[i])) return keys[i];
+			if(!strategy.equals(keys[i], EMPTY_KEY_VALUE) && filter.test(keys[i])) return OPTIONAL.GET_OPTIONAL(keys[i]);
 		}
-		return EMPTY_VALUE;
+		return OPTIONAL.empty();
 	}
 	
 	@Override
--- a/src/builder/resources/speiger/assets/collections/templates/sets/OpenHashSet.template
+++ b/src/builder/resources/speiger/assets/collections/templates/sets/OpenHashSet.template
@ -6,6 +6,9 @@ import java.util.ConcurrentModificationException;
 import java.util.Iterator;
 import java.util.NoSuchElementException;
 import java.util.Objects;
+#if JDK_TYPE
+import java.util.OPTIONAL;
+#endif
 #if TYPE_OBJECT
 import java.util.function.Consumer;
 import java.util.function.BiFunction;
@ -20,6 +23,9 @@ import speiger.src.collections.PACKAGE.collections.ITERATOR;
 import speiger.src.collections.PACKAGE.utils.ITERATORS;
 import speiger.src.collections.PACKAGE.functions.CONSUMER;
 #endif
+#if !JDK_TYPE 
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#endif
 import speiger.src.collections.ints.functions.consumer.BI_FROM_INT_CONSUMER;
 import speiger.src.collections.objects.functions.consumer.BI_FROM_OBJECT_CONSUMER;
 #if !JDK_FUNCTION
@ -498,7 +504,7 @@ public class HASH_SET KEY_GENERIC_TYPE extends ABSTRACT_SET KEY_GENERIC_TYPE imp
 	
 #endif
 	@Override
-	public KEY_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+	public OPTIONAL KEY_GENERIC_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 		Objects.requireNonNull(operator);
 		KEY_TYPE state = EMPTY_VALUE;
 		boolean empty = true;
@ -515,18 +521,18 @@ public class HASH_SET KEY_GENERIC_TYPE extends ABSTRACT_SET KEY_GENERIC_TYPE imp
 			}
 			state = operator.APPLY_VALUE(state, keys[i]);
 		}
-		return state;
+		return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 	}
 	
 	@Override
-	public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+	public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 		Objects.requireNonNull(filter);
-		if(size() <= 0) return EMPTY_VALUE;
-		if(containsNull && filter.test(keys[nullIndex])) return keys[nullIndex];
+		if(size() <= 0) return OPTIONAL.empty();
+		if(containsNull && filter.test(keys[nullIndex])) return OPTIONAL.GET_OPTIONAL(keys[nullIndex]);
 		for(int i = nullIndex-1;i>=0;i--) {
-			if(KEY_EQUALS_NOT_NULL(keys[i]) && filter.test(keys[i])) return keys[i];
+			if(KEY_EQUALS_NOT_NULL(keys[i]) && filter.test(keys[i])) return OPTIONAL.GET_OPTIONAL(keys[i]);
 		}
-		return EMPTY_VALUE;
+		return OPTIONAL.empty();
 	}
 	
 	@Override
--- a/src/builder/resources/speiger/assets/collections/templates/sets/RBTreeSet.template
+++ b/src/builder/resources/speiger/assets/collections/templates/sets/RBTreeSet.template
@ -2,6 +2,9 @@ package speiger.src.collections.PACKAGE.sets;

 import java.util.Collection;
 import java.util.Collections;
+#if JDK_TYPE
+import java.util.OPTIONAL;
+#endif
 #if TYPE_OBJECT
 import java.util.Comparator;
 import java.util.function.Consumer;
@ -19,6 +22,9 @@ import speiger.src.collections.PACKAGE.collections.BI_ITERATOR;
 import speiger.src.collections.PACKAGE.functions.COMPARATOR;
 import speiger.src.collections.PACKAGE.functions.CONSUMER;
 #endif
+#if !JDK_TYPE 
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#endif
 import speiger.src.collections.ints.functions.consumer.BI_FROM_INT_CONSUMER;
 import speiger.src.collections.objects.functions.consumer.BI_FROM_OBJECT_CONSUMER;
 #if !JDK_FUNCTION
@ -427,7 +433,7 @@ public class RB_TREE_SET KEY_GENERIC_TYPE extends ABSTRACT_SET KEY_GENERIC_TYPE
 	
 #endif
 	@Override
-	public KEY_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+	public OPTIONAL KEY_GENERIC_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 		Objects.requireNonNull(operator);
 		KEY_TYPE state = EMPTY_VALUE;
 		boolean empty = true;
@ -439,16 +445,16 @@ public class RB_TREE_SET KEY_GENERIC_TYPE extends ABSTRACT_SET KEY_GENERIC_TYPE
 			}
 			state = operator.APPLY_VALUE(state, entry.key);
 		}
-		return state;
+		return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 	}
 	
 	@Override
-	public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+	public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 		Objects.requireNonNull(filter);
 		for(Entry KEY_GENERIC_TYPE entry = first;entry != null;entry = entry.next()) {
-			if(filter.test(entry.key)) return entry.key;
+			if(filter.test(entry.key)) return OPTIONAL.GET_OPTIONAL(entry.key);
 		}
-		return EMPTY_VALUE;
+		return OPTIONAL.empty();
 	}
 	
 	@Override
@ -1374,7 +1380,7 @@ public class RB_TREE_SET KEY_GENERIC_TYPE extends ABSTRACT_SET KEY_GENERIC_TYPE
 		
 #endif
 		@Override
-		public KEY_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
+		public OPTIONAL KEY_GENERIC_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) {
 			Objects.requireNonNull(operator);
 			KEY_TYPE state = EMPTY_VALUE;
 			boolean empty = true;
@ -1386,16 +1392,16 @@ public class RB_TREE_SET KEY_GENERIC_TYPE extends ABSTRACT_SET KEY_GENERIC_TYPE
 				}
 				state = operator.APPLY_VALUE(state, entry.key);
 			}
-			return state;
+			return empty ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(state);
 		}
 		
 		@Override
-		public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
+		public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) {
 			Objects.requireNonNull(filter);
 			for(Entry KEY_GENERIC_TYPE entry = start();entry != null && inRange(entry.key);entry = next(entry)) {
-				if(filter.test(entry.key)) return entry.key;
+				if(filter.test(entry.key)) return OPTIONAL.GET_OPTIONAL(entry.key);
 			}
-			return EMPTY_VALUE;
+			return OPTIONAL.empty();
 		}
 		
 		@Override
--- a/src/builder/resources/speiger/assets/collections/templates/utils/Collections.template
+++ b/src/builder/resources/speiger/assets/collections/templates/utils/Collections.template
@ -8,6 +8,9 @@ import java.util.ConcurrentModificationException;
 import java.util.Iterator;
 import java.util.NoSuchElementException;
 import java.util.Objects;
+#if JDK_TYPE
+import java.util.OPTIONAL;
+#endif
 #if TYPE_OBJECT
 import java.util.Comparator;
 import java.util.function.BiFunction;
@ -30,6 +33,9 @@ import speiger.src.collections.PACKAGE.collections.ITERATOR;
 #if !TYPE_OBJECT
 import speiger.src.collections.PACKAGE.functions.COMPARATOR;
 #endif
+#if !JDK_TYPE 
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#endif
 #if !TYPE_OBJECT
 import speiger.src.collections.objects.utils.ObjectArrays;
 import speiger.src.collections.PACKAGE.functions.CONSUMER;
@ -869,9 +875,9 @@ public class COLLECTIONS
 		public KEY_TYPE reduce(KEY_TYPE identity, UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) { synchronized(mutex) { return c.reduce(identity, operator); } }
 #endif
 		@Override
-		public KEY_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) { synchronized(mutex) { return c.reduce(operator); } }
+		public OPTIONAL KEY_GENERIC_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) { synchronized(mutex) { return c.reduce(operator); } }
 		@Override
-		public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) { synchronized(mutex) { return c.findFirst(filter); } }
+		public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) { synchronized(mutex) { return c.findFirst(filter); } }
 		@Override
 		public int count(PREDICATE KEY_GENERIC_TYPE filter) { synchronized(mutex) { return c.count(filter); } }
 	}
@ -1021,9 +1027,9 @@ public class COLLECTIONS
 		public KEY_TYPE reduce(KEY_TYPE identity, UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) { return c.reduce(identity, operator); }
 #endif
 		@Override
-		public KEY_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) { return c.reduce(operator); }
+		public OPTIONAL KEY_GENERIC_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) { return c.reduce(operator); }
 		@Override
-		public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) { return c.findFirst(filter); }
+		public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) { return c.findFirst(filter); }
 		@Override
 		public int count(PREDICATE KEY_GENERIC_TYPE filter) { return c.count(filter); }
 	}
--- a/src/builder/resources/speiger/assets/collections/templates/utils/PriorityQueues.template
+++ b/src/builder/resources/speiger/assets/collections/templates/utils/PriorityQueues.template
@ -4,16 +4,22 @@ package speiger.src.collections.PACKAGE.utils;
 import java.util.Collection;
 import java.util.Comparator;
 import java.util.function.Consumer;
+import java.util.function.BiFunction;
 #endif
 #if JDK_FUNCTION
 import java.util.function.PREDICATE;
 #endif
-
+#if JDK_TYPE
+import java.util.OPTIONAL;
+#endif
 import speiger.src.collections.PACKAGE.collections.ITERATOR;
 import speiger.src.collections.PACKAGE.collections.COLLECTION;
 #if !TYPE_OBJECT
 import speiger.src.collections.PACKAGE.functions.COMPARATOR;
 #endif
+#if !JDK_TYPE 
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#endif
 #if DEQUEUE_FEATURE
 import speiger.src.collections.PACKAGE.queues.PRIORITY_DEQUEUE;
 #endif
@ -24,6 +30,7 @@ import speiger.src.collections.PACKAGE.functions.CONSUMER;
 #if !JDK_FUNCTION
 import speiger.src.collections.PACKAGE.functions.function.PREDICATE;
 #endif
+import speiger.src.collections.PACKAGE.functions.function.UNARY_OPERATOR;
 import speiger.src.collections.objects.functions.consumer.BI_FROM_OBJECT_CONSUMER;

 /**
@ -140,7 +147,15 @@ public class PRIORITY_QUEUES
 		@Override
 		public boolean matchesAll(PREDICATE KEY_GENERIC_TYPE filter) { synchronized(mutex) { return queue.matchesAll(filter); } }
 		@Override
-		public KEY_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) { synchronized(mutex) { return queue.findFirst(filter); } }
+		public OPTIONAL KEY_GENERIC_TYPE findFirst(PREDICATE KEY_GENERIC_TYPE filter) { synchronized(mutex) { return queue.findFirst(filter); } }
+		#if TYPE_OBJECT
+		public <KEY_SPECIAL_TYPE> KEY_SPECIAL_TYPE reduce(KEY_SPECIAL_TYPE identity, BiFunction<KEY_SPECIAL_TYPE, KEY_TYPE, KEY_SPECIAL_TYPE> operator) { synchronized(mutex) { return queue.reduce(identity, operator); } }
+#else
+		@Override
+		public KEY_TYPE reduce(KEY_TYPE identity, UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) { synchronized(mutex) { return queue.reduce(identity, operator); } }
+#endif
+		@Override
+		public OPTIONAL KEY_GENERIC_TYPE reduce(UNARY_OPERATOR KEY_KEY_GENERIC_TYPE operator) { synchronized(mutex) { return queue.reduce(operator); } }
 		@Override
 		public int count(PREDICATE KEY_GENERIC_TYPE filter) { synchronized(mutex) { return queue.count(filter); } }
 	}
--- a/src/builder/resources/speiger/assets/testers/templates/tests/collection/CollectionForEachTester.template
+++ b/src/builder/resources/speiger/assets/testers/templates/tests/collection/CollectionForEachTester.template
@ -26,6 +26,15 @@ public class FILE_KEY_TYPECollectionForEachTester KEY_GENERIC_TYPE extends ABSTR
 		HELPERS.assertContentsAnyOrder(elements, createSamplesArray());
 	}

+#ignore
+	@CollectionFeature.Require(absent = KNOWN_ORDER)
+	public void testIndexedForEachUnknownOrder() {
+#endignore
+		LIST KEY_GENERIC_TYPE elements = new ARRAY_LISTBRACES();
+		collection.forEachIndexed((K, V) -> elements.add(V));
+		HELPERS.assertContentsAnyOrder(elements, createSamplesArray());
+	}
+	
 #ignore
@CollectionFeature.Require(absent = KNOWN_ORDER)
 	public void testForEachExtraUnknownOrder() {
@ -44,6 +53,15 @@ public class FILE_KEY_TYPECollectionForEachTester KEY_GENERIC_TYPE extends ABSTR
 		assertEquals("Different ordered iteration", HELPERS.copyToList(getOrderedElements()), elements);
 	}

+#ignore
+	@CollectionFeature.Require(KNOWN_ORDER)
+	public void testIndexedForEachKnownOrder() {
+#endignore
+		LIST KEY_GENERIC_TYPE elements = new ARRAY_LISTBRACES();
+		collection.forEachIndexed((K, V) -> elements.add(V));
+		assertEquals("Different ordered iteration", HELPERS.copyToList(getOrderedElements()), elements);
+	}
+	
 #ignore
 	@CollectionFeature.Require(KNOWN_ORDER)
 	public void testForEachExtraKnownOrder() {
--- a/src/builder/resources/speiger/assets/testers/templates/tests/iterable/IterableFindFirstTester.template
+++ b/src/builder/resources/speiger/assets/testers/templates/tests/iterable/IterableFindFirstTester.template
@ -4,6 +4,12 @@ package speiger.src.testers.PACKAGE.tests.iterable;
 import java.util.Objects;

 #endif
+#if JDK_TYPE
+import java.util.OPTIONAL;
+#else
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
+#endif
+
 import org.junit.Ignore;

 import com.google.common.collect.testing.features.CollectionSize;
@ -27,17 +33,17 @@ public class FILE_KEY_TYPEIterableFindFirstTester KEY_GENERIC_TYPE extends ABSTR
 	@CollectionSize.Require(absent = CollectionSize.ZERO)
 #endignore
 	public void testIterableFindFirst_FindFirstElements() {
-		assertEquals("First Element should be found", e0(), container.findFirst(T -> KEY_EQUALS(T, e0())));
+		assertEquals("First Element should be found", e0(), container.findFirst(T -> KEY_EQUALS(T, e0())).SUPPLY_GET());
 	}
 	
 	public void testIterableFindFirst_FindNothing() {
-		assertEquals("No element should be found", EMPTY_KEY_VALUE, container.findFirst(T -> KEY_EQUALS(T, e4())));
+		assertEquals("No element should be found", OPTIONAL.empty(), container.findFirst(T -> KEY_EQUALS(T, e4())));
 	}
 	
 #ignore
 	@CollectionSize.Require(CollectionSize.SEVERAL)
 #endignore
 	public void testIterableFindFirst_FindLastElement() {
-		assertEquals("Last Element should be found", e2(), container.findFirst(T -> KEY_EQUALS(T, e2())));
+		assertEquals("Last Element should be found", e2(), container.findFirst(T -> KEY_EQUALS(T, e2())).SUPPLY_GET());
 	}
 }
--- a/src/builder/resources/speiger/assets/testers/templates/tests/iterable/IterableReduceTester.template
+++ b/src/builder/resources/speiger/assets/testers/templates/tests/iterable/IterableReduceTester.template
@ -3,9 +3,16 @@ package speiger.src.testers.PACKAGE.tests.iterable;
 #if TYPE_OBJECT
 import java.util.Objects;

+#endif
+#if JDK_TYPE
+import java.util.OPTIONAL;
+#else
+import speiger.src.collections.PACKAGE.functions.OPTIONAL;
 #endif
 import org.junit.Ignore;

+import com.google.common.collect.testing.features.CollectionSize;
+
 import speiger.src.testers.PACKAGE.tests.base.ABSTRACT_COLLECTION_TESTER;

@Ignore
@ -29,7 +36,7 @@ public class FILE_KEY_TYPEIterableReduceTester KEY_GENERIC_TYPE extends ABSTRACT
 	}
 	
 	public void testIterableReduce() {
-		assertEquals("The sum of the collection should match", getSum(), collection.reduce(this::sum));
+		assertEquals("The sum of the collection should match", size == CollectionSize.ZERO ? OPTIONAL.empty() : OPTIONAL.GET_OPTIONAL(getSum()), collection.reduce(this::sum));
 	}
 	
 	public void testIterableExtraReduce() {
--- a/src/test/java/speiger/src/collections/ints/base/BaseIntIterableTest.java
+++ b/src/test/java/speiger/src/collections/ints/base/BaseIntIterableTest.java
@ -96,7 +96,7 @@ public abstract class BaseIntIterableTest
 	public void testStreamFindFirst() {
 		if(getValidIterableTests().contains(IterableTest.STREAM_FIND_FIRST)) {
 			int expected = IntStream.of(TEST_ARRAY).filter(T -> T / 50 > 0).findFirst().getAsInt();
-			int actual = create(TEST_ARRAY).findFirst(T -> T / 50 > 0);
+			int actual = create(TEST_ARRAY).findFirst(T -> T / 50 > 0).getAsInt();
 			Assert.assertEquals(expected, actual);
 		}
 	}
Author	SHA1	Message	Date
Speiger	3d39d5526d	Breaking update - Added: Optionals for the missing JDK ones. - Removed: Default values for Reduce and FindFirst. Using Optionals instead.	2026-05-11 18:00:00 +02:00
Speiger	c6f656ee66	Switched to yearly activity	2026-05-11 00:36:08 +02:00