Added interface to JDK collector API

11 files changed, 408 insertions, 12 deletions

diff --git a/BJC-Utils2/src/main/java/bjc/utils/data/BoundLazyPair.java b/BJC-Utils2/src/main/java/bjc/utils/data/BoundLazyPair.java
index 1635e06..dcf9cca 100644
--- a/BJC-Utils2/src/main/java/bjc/utils/data/BoundLazyPair.java
+++ b/BJC-Utils2/src/main/java/bjc/utils/data/BoundLazyPair.java
@@ -26,8 +26,8 @@ class BoundLazyPair<OldLeft, OldRight, NewLeft, NewRight>
 	@Override
 	public <BoundLeft, BoundRight> IPair<BoundLeft, BoundRight> bind(
 			BiFunction<NewLeft, NewRight, IPair<BoundLeft, BoundRight>> bindr) {
-		IHolder<IPair<NewLeft, NewRight>> newPair = new Identity<>(
-				boundPair);
+		IHolder<IPair<NewLeft, NewRight>> newPair =
+				new Identity<>(boundPair);
 		IHolder<Boolean> newPairMade = new Identity<>(pairBound);
 
 		Supplier<NewLeft> leftSupp = () -> {
@@ -93,8 +93,8 @@ class BoundLazyPair<OldLeft, OldRight, NewLeft, NewRight>
 	public <MergedType> MergedType
 			merge(BiFunction<NewLeft, NewRight, MergedType> merger) {
 		if (!pairBound) {
-			boundPair = binder.apply(leftSupplier.get(),
-					rightSupplier.get());
+			boundPair =
+					binder.apply(leftSupplier.get(), rightSupplier.get());
 
 			pairBound = true;
 		}
@@ -166,4 +166,19 @@ class BoundLazyPair<OldLeft, OldRight, NewLeft, NewRight>
 
 		return new LazyPair<>(leftSupp, rightSupp);
 	}
+
+	@Override
+	public <OtherLeft, OtherRight, CombinedLeft, CombinedRight>
+			IPair<CombinedLeft, CombinedRight>
+			combine(IPair<OtherLeft, OtherRight> otherPair,
+					BiFunction<NewLeft, OtherLeft, CombinedLeft> leftCombiner,
+					BiFunction<NewRight, OtherRight, CombinedRight> rightCombiner) {
+		return otherPair.bind((otherLeft, otherRight) -> {
+			return bind((leftVal, rightVal) -> {
+				return new LazyPair<>(
+						leftCombiner.apply(leftVal, otherLeft),
+						rightCombiner.apply(rightVal, otherRight));
+			});
+		});
+	}
 }
\ No newline at end of file
diff --git a/BJC-Utils2/src/main/java/bjc/utils/data/Either.java b/BJC-Utils2/src/main/java/bjc/utils/data/Either.java
new file mode 100644
index 0000000..8787888
--- /dev/null
+++ b/BJC-Utils2/src/main/java/bjc/utils/data/Either.java
@@ -0,0 +1,135 @@
+package bjc.utils.data;
+
+import java.util.function.BiFunction;
+import java.util.function.Function;
+
+/**
+ * Represents a pair where only one side has a value
+ * 
+ * @author ben
+ * @param <LeftType>
+ *            The type that could be on the left
+ * @param <RightType>
+ *            The type that could be on the right
+ *
+ */
+public class Either<LeftType, RightType>
+		implements IPair<LeftType, RightType> {
+	private LeftType	leftVal;
+	private RightType	rightVal;
+
+	private boolean		isLeft;
+
+	private Either(LeftType left, RightType right) {
+		if (left == null) {
+			rightVal = right;
+		} else {
+			leftVal = left;
+
+			isLeft = true;
+		}
+	}
+
+	/**
+	 * Create a new either with the left value occupied
+	 * 
+	 * @param <LeftType>
+	 *            The type of the left value
+	 * @param <RightType>
+	 *            The type of the empty right value
+	 * @param left
+	 *            The value to put on the left
+	 * @return An either with the left side occupied
+	 */
+	public static <LeftType, RightType> Either<LeftType, RightType>
+			fromLeft(LeftType left) {
+		return new Either<>(left, null);
+	}
+
+	/**
+	 * Create a new either with the right value occupied
+	 * 
+	 * @param <LeftType>
+	 *            The type of the empty left value
+	 * @param <RightType>
+	 *            The type of the right value
+	 * @param right
+	 *            The value to put on the right
+	 * @return An either with the right side occupied
+	 */
+	public static <LeftType, RightType> Either<LeftType, RightType>
+			fromRight(RightType right) {
+		return new Either<>(null, right);
+	}
+
+	@Override
+	public <BoundLeft, BoundRight> IPair<BoundLeft, BoundRight> bind(
+			BiFunction<LeftType, RightType, IPair<BoundLeft, BoundRight>> binder) {
+		return binder.apply(leftVal, rightVal);
+	}
+
+	@Override
+	public <BoundLeft> IPair<BoundLeft, RightType> bindLeft(
+			Function<LeftType, IPair<BoundLeft, RightType>> leftBinder) {
+		if (isLeft) {
+			return leftBinder.apply(leftVal);
+		}
+
+		return new Either<>(null, rightVal);
+	}
+
+	@Override
+	public <BoundRight> IPair<LeftType, BoundRight> bindRight(
+			Function<RightType, IPair<LeftType, BoundRight>> rightBinder) {
+		if (isLeft) {
+			return new Either<>(leftVal, null);
+		}
+
+		return rightBinder.apply(rightVal);
+	}
+
+	@Override
+	public <NewLeft> IPair<NewLeft, RightType>
+			mapLeft(Function<LeftType, NewLeft> mapper) {
+		if (isLeft) {
+			return new Either<>(mapper.apply(leftVal), null);
+		}
+
+		return new Either<>(null, rightVal);
+	}
+
+	@Override
+	public <NewRight> IPair<LeftType, NewRight>
+			mapRight(Function<RightType, NewRight> mapper) {
+		if (isLeft) {
+			return new Either<>(leftVal, null);
+		}
+
+		return new Either<>(null, mapper.apply(rightVal));
+	}
+
+	@Override
+	public <MergedType> MergedType
+			merge(BiFunction<LeftType, RightType, MergedType> merger) {
+		return merger.apply(leftVal, rightVal);
+	}
+
+	@Override
+	public <OtherLeft, OtherRight, CombinedLeft, CombinedRight>
+			IPair<CombinedLeft, CombinedRight>
+			combine(IPair<OtherLeft, OtherRight> otherPair,
+					BiFunction<LeftType, OtherLeft, CombinedLeft> leftCombiner,
+					BiFunction<RightType, OtherRight, CombinedRight> rightCombiner) {
+		if (isLeft) {
+			return otherPair.bind((otherLeft, otherRight) -> {
+				return new Either<>(leftCombiner.apply(leftVal, otherLeft),
+						null);
+			});
+		}
+
+		return otherPair.bind((otherLeft, otherRight) -> {
+			return new Either<>(null,
+					rightCombiner.apply(rightVal, otherRight));
+		});
+	}
+}
diff --git a/BJC-Utils2/src/main/java/bjc/utils/data/HalfBoundLazyPair.java b/BJC-Utils2/src/main/java/bjc/utils/data/HalfBoundLazyPair.java
index 9e26924..198dd96 100644
--- a/BJC-Utils2/src/main/java/bjc/utils/data/HalfBoundLazyPair.java
+++ b/BJC-Utils2/src/main/java/bjc/utils/data/HalfBoundLazyPair.java
@@ -138,4 +138,19 @@ class HalfBoundLazyPair<OldType, NewLeft, NewRight>
 
 		return new LazyPair<>(leftSupp, rightSupp);
 	}
+	
+	@Override
+	public <OtherLeft, OtherRight, CombinedLeft, CombinedRight>
+			IPair<CombinedLeft, CombinedRight>
+			combine(IPair<OtherLeft, OtherRight> otherPair,
+					BiFunction<NewLeft, OtherLeft, CombinedLeft> leftCombiner,
+					BiFunction<NewRight, OtherRight, CombinedRight> rightCombiner) {
+		return otherPair.bind((otherLeft, otherRight) -> {
+			return bind((leftVal, rightVal) -> {
+				return new LazyPair<>(
+						leftCombiner.apply(leftVal, otherLeft),
+						rightCombiner.apply(rightVal, otherRight));
+			});
+		});
+	}
 }
\ No newline at end of file
diff --git a/BJC-Utils2/src/main/java/bjc/utils/data/IPair.java b/BJC-Utils2/src/main/java/bjc/utils/data/IPair.java
index 707724b..f94d656 100644
--- a/BJC-Utils2/src/main/java/bjc/utils/data/IPair.java
+++ b/BJC-Utils2/src/main/java/bjc/utils/data/IPair.java
@@ -81,7 +81,8 @@ public interface IPair<LeftType, RightType>
 						"This function can only be applied to instances of IPair");
 			}
 
-			IPair<OldLeft, OldRight> argPair = (IPair<OldLeft, OldRight>) argumentPair;
+			IPair<OldLeft, OldRight> argPair =
+					(IPair<OldLeft, OldRight>) argumentPair;
 
 			return argPair.mapLeft(func);
 		};
@@ -98,7 +99,8 @@ public interface IPair<LeftType, RightType>
 						"This function can only be applied to instances of IPair");
 			}
 
-			IPair<OldLeft, OldRight> argPair = (IPair<OldLeft, OldRight>) argumentPair;
+			IPair<OldLeft, OldRight> argPair =
+					(IPair<OldLeft, OldRight>) argumentPair;
 
 			return argPair.mapRight(func);
 		};
@@ -163,4 +165,46 @@ public interface IPair<LeftType, RightType>
 	 */
 	public <MergedType> MergedType
 			merge(BiFunction<LeftType, RightType, MergedType> merger);
+
+	/**
+	 * Combine the contents of two pairs together
+	 * 
+	 * @param <OtherLeft>
+	 *            The type of the left value of the other pair
+	 * @param <OtherRight>
+	 *            The type of the right value of the other pair
+	 * @param <CombinedLeft>
+	 *            The type of the left value of the combined pair
+	 * @param <CombinedRight>
+	 *            The type of the right value of the combined pair
+	 * @param otherPair
+	 *            The other pair to combine with
+	 * @param leftCombiner
+	 * @param rightCombiner
+	 * @return A pair with its values combined
+	 */
+	public <OtherLeft, OtherRight, CombinedLeft, CombinedRight>
+			IPair<CombinedLeft, CombinedRight>
+			combine(IPair<OtherLeft, OtherRight> otherPair,
+					BiFunction<LeftType, OtherLeft, CombinedLeft> leftCombiner,
+					BiFunction<RightType, OtherRight, CombinedRight> rightCombiner);
+
+	/**
+	 * Pairwise combine two pairs together
+	 * 
+	 * @param <OtherLeft>
+	 *            The left type of the other pair
+	 * @param <OtherRight>
+	 *            The right type of the other pair
+	 * @param otherPair
+	 *            The pair to combine with
+	 * @return The pairs, pairwise combined together
+	 */
+	public default <OtherLeft, OtherRight>
+			IPair<IPair<LeftType, OtherLeft>, IPair<RightType, OtherRight>>
+			combine(IPair<OtherLeft, OtherRight> otherPair) {
+		return combine(otherPair,
+				(left, otherLeft) -> new Pair<>(left, otherLeft),
+				(right, otherRight) -> new Pair<>(right, otherRight));
+	}
 }
diff --git a/BJC-Utils2/src/main/java/bjc/utils/data/LazyPair.java b/BJC-Utils2/src/main/java/bjc/utils/data/LazyPair.java
index 6f1be10..d688e5b 100644
--- a/BJC-Utils2/src/main/java/bjc/utils/data/LazyPair.java
+++ b/BJC-Utils2/src/main/java/bjc/utils/data/LazyPair.java
@@ -198,4 +198,19 @@ public class LazyPair<LeftType, RightType>
 
 		return new LazyPair<>(leftSupp, rightSupp);
 	}
+
+	@Override
+	public <OtherLeft, OtherRight, CombinedLeft, CombinedRight>
+			IPair<CombinedLeft, CombinedRight>
+			combine(IPair<OtherLeft, OtherRight> otherPair,
+					BiFunction<LeftType, OtherLeft, CombinedLeft> leftCombiner,
+					BiFunction<RightType, OtherRight, CombinedRight> rightCombiner) {
+		return otherPair.bind((otherLeft, otherRight) -> {
+			return bind((leftVal, rightVal) -> {
+				return new LazyPair<>(
+						leftCombiner.apply(leftVal, otherLeft),
+						rightCombiner.apply(rightVal, otherRight));
+			});
+		});
+	}
 }
diff --git a/BJC-Utils2/src/main/java/bjc/utils/data/Pair.java b/BJC-Utils2/src/main/java/bjc/utils/data/Pair.java
index eb421bc..1fc0d19 100644
--- a/BJC-Utils2/src/main/java/bjc/utils/data/Pair.java
+++ b/BJC-Utils2/src/main/java/bjc/utils/data/Pair.java
@@ -104,4 +104,16 @@ public class Pair<LeftType, RightType>
 
 		return new Pair<>(leftValue, mapper.apply(rightValue));
 	}
+
+	@Override
+	public <OtherLeft, OtherRight, CombinedLeft, CombinedRight>
+			IPair<CombinedLeft, CombinedRight>
+			combine(IPair<OtherLeft, OtherRight> otherPair,
+					BiFunction<LeftType, OtherLeft, CombinedLeft> leftCombiner,
+					BiFunction<RightType, OtherRight, CombinedRight> rightCombiner) {
+		return otherPair.bind((otherLeft, otherRight) -> {
+			return new Pair<>(leftCombiner.apply(leftValue, otherLeft),
+					rightCombiner.apply(rightValue, otherRight));
+		});
+	}
 }
\ No newline at end of file
diff --git a/BJC-Utils2/src/main/java/bjc/utils/funcdata/IList.java b/BJC-Utils2/src/main/java/bjc/utils/funcdata/IList.java
index b6363e7..00ec653 100644
--- a/BJC-Utils2/src/main/java/bjc/utils/funcdata/IList.java
+++ b/BJC-Utils2/src/main/java/bjc/utils/funcdata/IList.java
@@ -6,6 +6,7 @@ import java.util.function.BiFunction;
 import java.util.function.Consumer;
 import java.util.function.Function;
 import java.util.function.Predicate;
+import java.util.stream.Collector;
 
 import bjc.utils.data.IPair;
 
@@ -18,7 +19,6 @@ import bjc.utils.data.IPair;
  *            The type in this list
  */
 public interface IList<ContainedType> {
-
 	/**
 	 * Add an item to this list
 	 * 
@@ -302,12 +302,35 @@ public interface IList<ContainedType> {
 	 *            The type of array to return
 	 * @return The list, as an array
 	 */
-	ContainedType[] toArray(ContainedType[] arrType);
+	public ContainedType[] toArray(ContainedType[] arrType);
 
 	/**
 	 * Convert the list into a iterable
 	 * 
 	 * @return An iterable view onto the list
 	 */
-	Iterable<ContainedType> toIterable();
+	public Iterable<ContainedType> toIterable();
+
+	/**
+	 * Reduce the contents of this list using a collector
+	 * 
+	 * @param <StateType>
+	 *            The intermediate accumulation type
+	 * @param <ReducedType>
+	 *            The final, reduced type
+	 * @param collector
+	 *            The collector to use for reduction
+	 * @return The reduced list
+	 */
+	public default <StateType, ReducedType> ReducedType collect(
+			Collector<ContainedType, StateType, ReducedType> collector) {
+		BiConsumer<StateType, ContainedType> accumulator =
+				collector.accumulator();
+
+		return reduceAux(collector.supplier().get(), (value, state) -> {
+			accumulator.accept(state, value);
+
+			return state;
+		}, collector.finisher());
+	}
 }
\ No newline at end of file
diff --git a/BJC-Utils2/src/main/java/bjc/utils/funcdata/IMap.java b/BJC-Utils2/src/main/java/bjc/utils/funcdata/IMap.java
index f5f7a26..243e58a 100644
--- a/BJC-Utils2/src/main/java/bjc/utils/funcdata/IMap.java
+++ b/BJC-Utils2/src/main/java/bjc/utils/funcdata/IMap.java
@@ -16,7 +16,6 @@ import java.util.function.Function;
  *
  */
 public interface IMap<KeyType, ValueType> {
-
 	/**
 	 * Check if this map contains the specified key
 	 * 
diff --git a/BJC-Utils2/src/main/java/bjc/utils/funcutils/CollectorUtils.java b/BJC-Utils2/src/main/java/bjc/utils/funcutils/CollectorUtils.java
new file mode 100644
index 0000000..a44059b
--- /dev/null
+++ b/BJC-Utils2/src/main/java/bjc/utils/funcutils/CollectorUtils.java
@@ -0,0 +1,41 @@
+package bjc.utils.funcutils;
+
+import java.util.stream.Collector;
+
+import bjc.utils.data.IHolder;
+import bjc.utils.data.IPair;
+
+/**
+ * Utilities for producing implementations of {@link Collector}
+ * 
+ * @author ben
+ *
+ */
+public class CollectorUtils {
+	/**
+	 * Create a collector that applies two collectors at once
+	 * 
+	 * @param <InitialType>
+	 *            The type of the collection to collect from
+	 * @param <AuxType1>
+	 *            The intermediate type of the first collector
+	 * @param <AuxType2>
+	 *            The intermediate type of the second collector
+	 * @param <FinalType1>
+	 *            The final type of the first collector
+	 * @param <FinalType2>
+	 *            The final type of the second collector
+	 * @param firstCollector
+	 *            The first collector to use
+	 * @param secondCollector
+	 *            The second collector to use
+	 * @return A collector that functions as mentioned above
+	 */
+	public static <InitialType, AuxType1, AuxType2, FinalType1, FinalType2>
+			Collector<InitialType, IHolder<IPair<AuxType1, AuxType2>>, IPair<FinalType1, FinalType2>>
+			compoundCollect(
+					Collector<InitialType, AuxType1, FinalType1> firstCollector,
+					Collector<InitialType, AuxType2, FinalType2> secondCollector) {
+		return new CompoundCollector<>(firstCollector, secondCollector);
+	}
+}
diff --git a/BJC-Utils2/src/main/java/bjc/utils/funcutils/CompoundCollector.java b/BJC-Utils2/src/main/java/bjc/utils/funcutils/CompoundCollector.java
new file mode 100644
index 0000000..715a6e5
--- /dev/null
+++ b/BJC-Utils2/src/main/java/bjc/utils/funcutils/CompoundCollector.java
@@ -0,0 +1,97 @@
+package bjc.utils.funcutils;
+
+import java.util.Set;
+import java.util.function.BiConsumer;
+import java.util.function.BinaryOperator;
+import java.util.function.Function;
+import java.util.function.Supplier;
+import java.util.stream.Collector;
+import java.util.stream.Collector.Characteristics;
+
+import bjc.utils.data.IHolder;
+import bjc.utils.data.IPair;
+import bjc.utils.data.Identity;
+import bjc.utils.data.Pair;
+
+final class CompoundCollector<InitialType, AuxType1, AuxType2, FinalType1, FinalType2>
+		implements
+		Collector<InitialType, IHolder<IPair<AuxType1, AuxType2>>, IPair<FinalType1, FinalType2>> {
+	private Set<java.util.stream.Collector.Characteristics>	characteristicSet;
+
+	private Collector<InitialType, AuxType1, FinalType1>	firstCollector;
+	private Collector<InitialType, AuxType2, FinalType2>	secondCollector;
+
+	public CompoundCollector(
+			Collector<InitialType, AuxType1, FinalType1> firstCollector,
+			Collector<InitialType, AuxType2, FinalType2> secondCollector) {
+		this.firstCollector = firstCollector;
+		this.secondCollector = secondCollector;
+
+		characteristicSet = firstCollector.characteristics();
+		characteristicSet.addAll(secondCollector.characteristics());
+	}
+
+	@Override
+	public Supplier<IHolder<IPair<AuxType1, AuxType2>>> supplier() {
+		return () -> new Identity<>(
+				new Pair<>(firstCollector.supplier().get(),
+						secondCollector.supplier().get()));
+	}
+
+	@Override
+	public BiConsumer<IHolder<IPair<AuxType1, AuxType2>>, InitialType>
+			accumulator() {
+		BiConsumer<AuxType1, InitialType> firstAccumulator =
+				firstCollector.accumulator();
+		BiConsumer<AuxType2, InitialType> secondAccumulator =
+				secondCollector.accumulator();
+
+		return (state, value) -> {
+			state.doWith((statePair) -> {
+				statePair.doWith((leftState, rightState) -> {
+					firstAccumulator.accept(leftState, value);
+					secondAccumulator.accept(rightState, value);
+				});
+			});
+		};
+	}
+
+	@Override
+	public BinaryOperator<IHolder<IPair<AuxType1, AuxType2>>>
+			combiner() {
+		BinaryOperator<AuxType1> firstCombiner =
+				firstCollector.combiner();
+		BinaryOperator<AuxType2> secondCombiner =
+				secondCollector.combiner();
+
+		return (leftState, rightState) -> {
+			return leftState.unwrap((leftPair) -> {
+				return rightState.transform((rightPair) -> {
+					return leftPair.combine(rightPair, firstCombiner,
+							secondCombiner);
+				});
+			});
+		};
+	}
+
+	@Override
+	public Function<IHolder<IPair<AuxType1, AuxType2>>, IPair<FinalType1, FinalType2>>
+			finisher() {
+		return (state) -> {
+			return state.unwrap((pair) -> {
+				return pair.bind((leftVal, rightVal) -> {
+					return new Pair<>(
+							firstCollector.finisher().apply(leftVal),
+							secondCollector.finisher()
+									.apply(rightVal));
+				});
+			});
+		};
+	}
+
+	@Override
+	public Set<java.util.stream.Collector.Characteristics>
+			characteristics() {
+		return characteristicSet;
+	}
+}
\ No newline at end of file
diff --git a/BJC-Utils2/src/main/java/bjc/utils/funcutils/FuncUtils.java b/BJC-Utils2/src/main/java/bjc/utils/funcutils/FuncUtils.java
index 4209e6d..43603d6 100644
--- a/BJC-Utils2/src/main/java/bjc/utils/funcutils/FuncUtils.java
+++ b/BJC-Utils2/src/main/java/bjc/utils/funcutils/FuncUtils.java
@@ -1,8 +1,8 @@
 package bjc.utils.funcutils;
 
 import java.util.function.BiFunction;
+import java.util.function.Consumer;
 import java.util.function.Function;
-import java.util.function.IntConsumer;
 
 /**
  * Utility things for functions
@@ -41,7 +41,7 @@ public class FuncUtils {
 	 * @param cons
 	 *            The action to perform
 	 */
-	public static void doTimes(int nTimes, IntConsumer cons) {
+	public static void doTimes(int nTimes, Consumer<Integer> cons) {
 		for (int i = 0; i < nTimes; i++) {
 			cons.accept(i);
 		}