diff options
| author | bculkin2442 <bjculkin@mix.wvu.edu> | 2016-04-17 15:01:44 -0400 |
|---|---|---|
| committer | bculkin2442 <bjculkin@mix.wvu.edu> | 2016-04-17 15:01:44 -0400 |
| commit | 77fcc58d1facffbc3af50be8c05985350e9f1355 (patch) | |
| tree | b7b81d24c107e644924dc526f8bb034efc62d2dc /BJC-Utils2/src/main/java/bjc/utils/data/experimental/LazyPair.java | |
| parent | a5850915df72f5968fd1b281eb9e455d50c580ee (diff) | |
Code maintenace and changes
Diffstat (limited to 'BJC-Utils2/src/main/java/bjc/utils/data/experimental/LazyPair.java')
| -rw-r--r-- | BJC-Utils2/src/main/java/bjc/utils/data/experimental/LazyPair.java | 317 |
1 files changed, 0 insertions, 317 deletions
diff --git a/BJC-Utils2/src/main/java/bjc/utils/data/experimental/LazyPair.java b/BJC-Utils2/src/main/java/bjc/utils/data/experimental/LazyPair.java deleted file mode 100644 index 04a4b61..0000000 --- a/BJC-Utils2/src/main/java/bjc/utils/data/experimental/LazyPair.java +++ /dev/null @@ -1,317 +0,0 @@ -package bjc.utils.data.experimental; - -import java.util.function.BiFunction; -import java.util.function.Function; -import java.util.function.Supplier; - -/** - * A lazy implementation of a pair - * - * @author ben - * - * @param <LeftType> - * The type on the left side of the pair - * @param <RightType> - * The type on the right side of the pair - */ -public class LazyPair<LeftType, RightType> - implements IPair<LeftType, RightType> { - private static class HalfBoundLazyPair<OldType, NewLeft, NewRight> - implements IPair<NewLeft, NewRight> { - private Supplier<OldType> oldSupplier; - - private Function<OldType, IPair<NewLeft, NewRight>> binder; - - private IPair<NewLeft, NewRight> boundPair; - private boolean pairBound; - - public HalfBoundLazyPair(Supplier<OldType> oldSupp, - Function<OldType, IPair<NewLeft, NewRight>> bindr) { - oldSupplier = oldSupp; - binder = bindr; - } - - @Override - public <BoundLeft> IPair<BoundLeft, NewRight> bindLeft( - Function<NewLeft, IPair<BoundLeft, NewRight>> leftBinder) { - Supplier<NewLeft> leftSupp = () -> { - IPair<NewLeft, NewRight> newPair = boundPair; - - if (!pairBound) { - newPair = binder.apply(oldSupplier.get()); - } - - return newPair.getLeft(); - }; - - return new HalfBoundLazyPair<>(leftSupp, leftBinder); - } - - @Override - public <BoundRight> IPair<NewLeft, BoundRight> bindRight( - Function<NewRight, IPair<NewLeft, BoundRight>> rightBinder) { - Supplier<NewRight> rightSupp = () -> { - IPair<NewLeft, NewRight> newPair = boundPair; - - if (!pairBound) { - newPair = binder.apply(oldSupplier.get()); - } - - return newPair.getRight(); - }; - - return new HalfBoundLazyPair<>(rightSupp, rightBinder); - } - - @Override - public <BoundLeft, BoundRight> IPair<BoundLeft, BoundRight> bind( - BiFunction<NewLeft, NewRight, IPair<BoundLeft, BoundRight>> bindr) { - IHolder<IPair<NewLeft, NewRight>> newPair = new Identity<>( - boundPair); - IHolder<Boolean> newPairMade = new Identity<>(pairBound); - - Supplier<NewLeft> leftSupp = () -> { - if (!newPairMade.getValue()) { - newPair.replace(binder.apply(oldSupplier.get())); - newPairMade.replace(true); - } - - return newPair.unwrap((pair) -> pair.getLeft()); - }; - - Supplier<NewRight> rightSupp = () -> { - if (!newPairMade.getValue()) { - newPair.replace(binder.apply(oldSupplier.get())); - newPairMade.replace(true); - } - - return newPair.unwrap((pair) -> pair.getRight()); - }; - - return new BoundLazyPair<>(leftSupp, rightSupp, bindr); - } - - @Override - public <MergedType> MergedType merge( - BiFunction<NewLeft, NewRight, MergedType> merger) { - if (!pairBound) { - boundPair = binder.apply(oldSupplier.get()); - - pairBound = true; - } - - return boundPair.merge(merger); - } - } - - private static class BoundLazyPair<OldLeft, OldRight, NewLeft, NewRight> - implements IPair<NewLeft, NewRight> { - private Supplier<OldLeft> leftSupplier; - private Supplier<OldRight> rightSupplier; - - private BiFunction<OldLeft, OldRight, IPair<NewLeft, NewRight>> binder; - - private IPair<NewLeft, NewRight> boundPair; - - private boolean pairBound; - - public BoundLazyPair(Supplier<OldLeft> leftSupp, - Supplier<OldRight> rightSupp, - BiFunction<OldLeft, OldRight, IPair<NewLeft, NewRight>> bindr) { - leftSupplier = leftSupp; - rightSupplier = rightSupp; - binder = bindr; - } - - @Override - public <BoundLeft> IPair<BoundLeft, NewRight> bindLeft( - Function<NewLeft, IPair<BoundLeft, NewRight>> leftBinder) { - Supplier<NewLeft> leftSupp = () -> { - IPair<NewLeft, NewRight> newPair = boundPair; - - if (!pairBound) { - newPair = binder.apply(leftSupplier.get(), - rightSupplier.get()); - } - - return newPair.getLeft(); - }; - - return new HalfBoundLazyPair<>(leftSupp, leftBinder); - } - - @Override - public <BoundRight> IPair<NewLeft, BoundRight> bindRight( - Function<NewRight, IPair<NewLeft, BoundRight>> rightBinder) { - Supplier<NewRight> rightSupp = () -> { - IPair<NewLeft, NewRight> newPair = boundPair; - - if (!pairBound) { - newPair = binder.apply(leftSupplier.get(), - rightSupplier.get()); - } - - return newPair.getRight(); - }; - - return new HalfBoundLazyPair<>(rightSupp, rightBinder); - } - - @Override - public <BoundLeft, BoundRight> IPair<BoundLeft, BoundRight> bind( - BiFunction<NewLeft, NewRight, IPair<BoundLeft, BoundRight>> bindr) { - IHolder<IPair<NewLeft, NewRight>> newPair = new Identity<>( - boundPair); - IHolder<Boolean> newPairMade = new Identity<>(pairBound); - - return new BoundLazyPair<>(() -> { - if (!newPairMade.getValue()) { - newPair.replace(binder.apply(leftSupplier.get(), - rightSupplier.get())); - - newPairMade.replace(false); - } - - return newPair.unwrap((pair) -> pair.getLeft()); - }, () -> { - if (!newPairMade.getValue()) { - newPair.replace(binder.apply(leftSupplier.get(), - rightSupplier.get())); - - newPairMade.replace(false); - } - - return newPair.unwrap((pair) -> pair.getRight()); - }, bindr); - } - - @Override - public <MergedType> MergedType merge( - BiFunction<NewLeft, NewRight, MergedType> merger) { - if (!pairBound) { - boundPair = binder.apply(leftSupplier.get(), - rightSupplier.get()); - - pairBound = true; - } - - return boundPair.merge(merger); - } - } - - private LeftType leftValue; - private RightType rightValue; - - private Supplier<LeftType> leftSupplier; - private Supplier<RightType> rightSupplier; - - private boolean leftMaterialized; - private boolean rightMaterialized; - - /** - * Create a new lazy pair, using the set value s - * - * @param leftVal - * The value for the left side of the pair - * @param rightVal - * The value for the right side of the pair - */ - public LazyPair(LeftType leftVal, RightType rightVal) { - leftValue = leftVal; - rightValue = rightVal; - - leftMaterialized = true; - rightMaterialized = true; - } - - /** - * Create a new lazy pair from the given value sources - * - * @param leftSupp - * The source for a value on the left side of the pair - * @param rightSupp - * The source for a value on the right side of the pair - */ - public LazyPair(Supplier<LeftType> leftSupp, - Supplier<RightType> rightSupp) { - leftSupplier = leftSupp; - rightSupplier = rightSupp; - - leftMaterialized = false; - rightMaterialized = false; - } - - @Override - public <BoundLeft> IPair<BoundLeft, RightType> bindLeft( - Function<LeftType, IPair<BoundLeft, RightType>> leftBinder) { - Supplier<LeftType> leftSupp = () -> { - if (leftMaterialized) { - return leftValue; - } - - return leftSupplier.get(); - }; - - return new HalfBoundLazyPair<>(leftSupp, leftBinder); - } - - @Override - public <BoundRight> IPair<LeftType, BoundRight> bindRight( - Function<RightType, IPair<LeftType, BoundRight>> rightBinder) { - Supplier<RightType> rightSupp = () -> { - if (rightMaterialized) { - return rightValue; - } - - return rightSupplier.get(); - }; - - return new HalfBoundLazyPair<>(rightSupp, rightBinder); - } - - @Override - public <BoundLeft, BoundRight> IPair<BoundLeft, BoundRight> bind( - BiFunction<LeftType, RightType, IPair<BoundLeft, BoundRight>> binder) { - return new BoundLazyPair<>(leftSupplier, rightSupplier, binder); - } - - @Override - public <MergedType> MergedType merge( - BiFunction<LeftType, RightType, MergedType> merger) { - if (!leftMaterialized) { - leftValue = leftSupplier.get(); - - leftMaterialized = true; - } - - if (!rightMaterialized) { - rightValue = rightSupplier.get(); - - rightMaterialized = true; - } - - return merger.apply(leftValue, rightValue); - } - - @Override - public LeftType getLeft() { - if (!leftMaterialized) { - leftValue = leftSupplier.get(); - - leftMaterialized = true; - } - - return leftValue; - } - - @Override - public RightType getRight() { - if (!rightMaterialized) { - rightValue = rightSupplier.get(); - - rightMaterialized = true; - } - - return rightValue; - } -} |
