diff options
Diffstat (limited to 'base/src/main/java/bjc/utils/data/internals/BoundLazyPair.java')
| -rw-r--r-- | base/src/main/java/bjc/utils/data/internals/BoundLazyPair.java | 228 |
1 files changed, 0 insertions, 228 deletions
diff --git a/base/src/main/java/bjc/utils/data/internals/BoundLazyPair.java b/base/src/main/java/bjc/utils/data/internals/BoundLazyPair.java deleted file mode 100644 index 2ef0e4c..0000000 --- a/base/src/main/java/bjc/utils/data/internals/BoundLazyPair.java +++ /dev/null @@ -1,228 +0,0 @@ -package bjc.utils.data.internals; - -import java.util.function.BiFunction; -import java.util.function.Function; -import java.util.function.Supplier; - -import bjc.utils.data.IHolder; -import bjc.utils.data.IPair; -import bjc.utils.data.Identity; -import bjc.utils.data.LazyPair; - -/** - * Implements a lazy pair that has been bound. - * - * @author Ben Culkin - */ -@SuppressWarnings("javadoc") -public class BoundLazyPair<OldLeft, OldRight, NewLeft, NewRight> implements IPair<NewLeft, NewRight> { - /* The supplier of the left value. */ - private final Supplier<OldLeft> leftSupplier; - /* The supplier of the right value. */ - private final Supplier<OldRight> rightSupplier; - - /* The binder to transform values. */ - private final BiFunction<OldLeft, OldRight, IPair<NewLeft, NewRight>> binder; - - /* The bound pair. */ - private IPair<NewLeft, NewRight> boundPair; - - /* Whether the pair has been bound yet. */ - private boolean pairBound; - - /** - * Create a new bound lazy pair. - * - * @param leftSupp - * The supplier for the left value. - * - * @param rightSupp - * The supplier for the right value. - * - * @param bindr - * The function to use to bind the left and right into a new - * pair. - */ - public BoundLazyPair(final Supplier<OldLeft> leftSupp, final Supplier<OldRight> rightSupp, - final BiFunction<OldLeft, OldRight, IPair<NewLeft, NewRight>> bindr) { - leftSupplier = leftSupp; - rightSupplier = rightSupp; - binder = bindr; - } - - @Override - public <BoundLeft, BoundRight> IPair<BoundLeft, BoundRight> bind( - final BiFunction<NewLeft, NewRight, IPair<BoundLeft, BoundRight>> bindr) { - if(bindr == null) throw new NullPointerException("Binder must not be null"); - - final IHolder<IPair<NewLeft, NewRight>> newPair = new Identity<>(boundPair); - final IHolder<Boolean> newPairMade = new Identity<>(pairBound); - - final Supplier<NewLeft> leftSupp = () -> { - if(!newPairMade.getValue()) { - /* - * If the pair hasn't been bound before, bind - * it. - */ - newPair.replace(binder.apply(leftSupplier.get(), rightSupplier.get())); - - newPairMade.replace(true); - } - - return newPair.unwrap((pair) -> pair.getLeft()); - }; - - final Supplier<NewRight> rightSupp = () -> { - if(!newPairMade.getValue()) { - /* - * If the pair hasn't been bound before, bind - * it. - */ - newPair.replace(binder.apply(leftSupplier.get(), rightSupplier.get())); - - newPairMade.replace(true); - } - - return newPair.unwrap((pair) -> pair.getRight()); - }; - - return new BoundLazyPair<>(leftSupp, rightSupp, bindr); - } - - @Override - public <BoundLeft> IPair<BoundLeft, NewRight> bindLeft( - final Function<NewLeft, IPair<BoundLeft, NewRight>> leftBinder) { - if(leftBinder == null) throw new NullPointerException("Left binder must not be null"); - - final Supplier<NewLeft> leftSupp = () -> { - IPair<NewLeft, NewRight> newPair = boundPair; - - if(!pairBound) { - /* - * If the pair hasn't been bound before, bind - * it. - */ - newPair = binder.apply(leftSupplier.get(), rightSupplier.get()); - } - - return newPair.getLeft(); - }; - - return new HalfBoundLazyPair<>(leftSupp, leftBinder); - } - - @Override - public <BoundRight> IPair<NewLeft, BoundRight> bindRight( - final Function<NewRight, IPair<NewLeft, BoundRight>> rightBinder) { - if(rightBinder == null) throw new NullPointerException("Right binder must not be null"); - - final Supplier<NewRight> rightSupp = () -> { - IPair<NewLeft, NewRight> newPair = boundPair; - - if(!pairBound) { - /* - * If the pair hasn't been bound before, bind - * it. - */ - newPair = binder.apply(leftSupplier.get(), rightSupplier.get()); - } - - return newPair.getRight(); - }; - - return new HalfBoundLazyPair<>(rightSupp, rightBinder); - } - - @Override - public <OtherLeft, OtherRight, CombinedLeft, CombinedRight> IPair<CombinedLeft, CombinedRight> combine( - final IPair<OtherLeft, OtherRight> otherPair, - final BiFunction<NewLeft, OtherLeft, CombinedLeft> leftCombiner, - final BiFunction<NewRight, OtherRight, CombinedRight> rightCombiner) { - if(otherPair == null) { - throw new NullPointerException("Other pair must not be null"); - } else if(leftCombiner == null) { - throw new NullPointerException("Left combiner must not be null"); - } else if(rightCombiner == null) { - throw new NullPointerException("Right combiner must not be null"); - } - - return otherPair.bind((otherLeft, otherRight) -> { - return bind((leftVal, rightVal) -> { - CombinedLeft cLeft = leftCombiner.apply(leftVal, otherLeft); - CombinedRight cRight = rightCombiner.apply(rightVal, otherRight); - - return new LazyPair<>(cLeft, cRight); - }); - }); - } - - @Override - public <NewLeftType> IPair<NewLeftType, NewRight> mapLeft(final Function<NewLeft, NewLeftType> mapper) { - if(mapper == null) throw new NullPointerException("Mapper must not be null"); - - final Supplier<NewLeftType> leftSupp = () -> { - if(!pairBound) { - final NewLeft leftVal = binder.apply(leftSupplier.get(), rightSupplier.get()).getLeft(); - - return mapper.apply(leftVal); - } - - return mapper.apply(boundPair.getLeft()); - }; - - final Supplier<NewRight> rightSupp = () -> { - if(!pairBound) return binder.apply(leftSupplier.get(), rightSupplier.get()).getRight(); - - return boundPair.getRight(); - }; - - return new LazyPair<>(leftSupp, rightSupp); - } - - @Override - public <NewRightType> IPair<NewLeft, NewRightType> mapRight(final Function<NewRight, NewRightType> mapper) { - if(mapper == null) throw new NullPointerException("Mapper must not be null"); - - final Supplier<NewLeft> leftSupp = () -> { - if(!pairBound) return binder.apply(leftSupplier.get(), rightSupplier.get()).getLeft(); - - return boundPair.getLeft(); - }; - - final Supplier<NewRightType> rightSupp = () -> { - if(!pairBound) { - final NewRight rightVal = binder.apply(leftSupplier.get(), rightSupplier.get()) - .getRight(); - - return mapper.apply(rightVal); - } - - return mapper.apply(boundPair.getRight()); - }; - - return new LazyPair<>(leftSupp, rightSupp); - } - - @Override - public <MergedType> MergedType merge(final BiFunction<NewLeft, NewRight, MergedType> merger) { - if(merger == null) throw new NullPointerException("Merger must not be null"); - - if(!pairBound) { - /* - * If the pair isn't bound yet, bind it. - */ - boundPair = binder.apply(leftSupplier.get(), rightSupplier.get()); - - pairBound = true; - } - - return boundPair.merge(merger); - } - - @Override - public String toString() { - if(pairBound) return boundPair.toString(); - - return "(un-materialized)"; - } -} |
