From 002516bd03b2ea3f731c8139c9a5f716902ab702 Mon Sep 17 00:00:00 2001 From: Ben Culkin Date: Tue, 7 Apr 2020 21:03:53 -0400 Subject: Finish remove utils.data utils.data now lives in the esodata project; not in this one --- .../bjc/utils/data/TopDownTransformIterator.java | 272 --------------------- 1 file changed, 272 deletions(-) delete mode 100644 base/src/main/java/bjc/utils/data/TopDownTransformIterator.java (limited to 'base/src/main/java/bjc/utils/data/TopDownTransformIterator.java') diff --git a/base/src/main/java/bjc/utils/data/TopDownTransformIterator.java b/base/src/main/java/bjc/utils/data/TopDownTransformIterator.java deleted file mode 100644 index f50ff68..0000000 --- a/base/src/main/java/bjc/utils/data/TopDownTransformIterator.java +++ /dev/null @@ -1,272 +0,0 @@ -package bjc.utils.data; - -import static bjc.utils.data.TopDownTransformResult.RTRANSFORM; - -import java.util.Deque; -import java.util.Iterator; -import java.util.LinkedList; -import java.util.NoSuchElementException; -import java.util.function.BiFunction; -import java.util.function.Consumer; -import java.util.function.Function; - -/* - * @TODO 10/11/17 Ben Culkin :TopDownStep - * - * Figure out what is broken with this, and fix it so that step-wise - * iteration works correctly. - */ - -/** - * An iterative top-down transform of a tree. - * - * @author EVE - * - * @param - * The type of the nodes in the tree. - */ -public class TopDownTransformIterator implements Iterator> { - /** - * Alias type for a tree transformation. - * - * @author student - * - * @param - * The type contained in the tree. - */ - public interface TreeTransform - extends BiFunction, Consumer>>, ITree> { - - } - - /* - * The function that picks how to transform a given node - */ - private final Function picker; - /* - * The transform to apply to a given node. - */ - private final TreeTransform transform; - - private ITree preParent; - private ITree postParent; - - private final Deque> preChildren; - private final Deque> postChildren; - - private TopDownTransformIterator curChild; - - private boolean done; - private boolean initial; - - private final Deque>> toYield; - private Iterator> currYield; - - /** - * Create a new tree iterator. - * - * @param pickr - * The function to use to pick how to process nodes. - * @param transfrm - * The transform to apply to the nodes. - * @param tree - * The tree to transform. - */ - public TopDownTransformIterator(final Function pickr, - final TreeTransform transfrm, final ITree tree) { - preParent = tree; - - preChildren = new LinkedList<>(); - postChildren = new LinkedList<>(); - toYield = new LinkedList<>(); - - picker = pickr; - transform = transfrm; - - done = false; - initial = true; - } - - /** - * Add a set of nodes to yield. - * - * @param src - * The nodes to yield. - */ - public void addYield(final Iterator> src) { - if (currYield != null) { - toYield.push(currYield); - } - - currYield = src; - } - - @Override - public boolean hasNext() { - return !done; - } - - /** - * Get the next yielded value. - * - * @param val - * The sentinel value to yield. - * - * @return The next yielded value. - */ - public ITree flushYields(final ITree val) { - if (currYield != null) { - /* - * We have non-sentinel values to yield. - */ - - /* - * Add the sentinel to yield later. - */ - toYield.add(new SingleIterator<>(val)); - - if (currYield.hasNext()) { - return currYield.next(); - } - - while (toYield.size() != 0 && !currYield.hasNext()) { - currYield = toYield.pop(); - } - - if (toYield.size() == 0 && !currYield.hasNext()) { - currYield = null; - return val; - } - - return currYield.next(); - } - - return val; - } - - @Override - public ITree next() { - if (done) - throw new NoSuchElementException(); - - /* - * Flush any values that need to be yielded. - */ - if (currYield != null) { - ITree yeld = flushYields(null); - - if (yeld != null) - return yeld; - } - - if (initial) { - /* - * Get the way we are transforming. - */ - final TopDownTransformResult res = picker.apply(preParent.getHead()); - - switch (res) { - case PASSTHROUGH: - postParent = new Tree<>(preParent.getHead()); - - if (preParent.getChildrenCount() != 0) { - for (int i = 0; i < preParent.getChildrenCount(); i++) { - preChildren.add(preParent.getChild(i)); - } - - // Return whatever the first child is - break; - } - - done = true; - return flushYields(postParent); - case SKIP: - done = true; - return flushYields(preParent); - case TRANSFORM: - done = true; - return flushYields(transform.apply(preParent, this::addYield)); - case RTRANSFORM: - preParent = transform.apply(preParent, this::addYield); - return flushYields(preParent); - case PUSHDOWN: - if (preParent.getChildrenCount() != 0) { - for (int i = 0; i < preParent.getChildrenCount(); i++) { - preChildren.add(preParent.getChild(i)); - } - - // Return whatever the first child is - break; - } - - done = true; - return flushYields(transform.apply(new Tree<>(preParent.getHead()), this::addYield)); - case PULLUP: - final ITree intRes = transform.apply(preParent, this::addYield); - - postParent = new Tree<>(intRes.getHead()); - - if (intRes.getChildrenCount() != 0) { - for (int i = 0; i < intRes.getChildrenCount(); i++) { - preChildren.add(intRes.getChild(i)); - } - - // Return whatever the first child is - break; - } - - done = true; - return flushYields(postParent); - default: - throw new IllegalArgumentException("Unknown result type " + res); - } - - if (res != RTRANSFORM) { - initial = false; - } - } - - if (curChild == null || !curChild.hasNext()) { - if (preChildren.size() != 0) { - curChild = new TopDownTransformIterator<>(picker, transform, preChildren.pop()); - - final ITree res = curChild.next(); - //System.out.println("\t\tTRACE: adding node " + res + " to children"); - postChildren.add(res); - - return flushYields(res); - } - - ITree res = null; - - if (postParent == null) { - res = new Tree<>(preParent.getHead()); - - //System.out.println("\t\tTRACE: adding nodes " + postChildren + " to " + res); - - for (final ITree child : postChildren) { - res.addChild(child); - } - - // res = transform.apply(res, - // this::addYield); - } else { - res = postParent; - - //System.out.println("\t\tTRACE: adding nodes " + postChildren + " to " + res); - for (final ITree child : postChildren) { - res.addChild(child); - } - } - - done = true; - return flushYields(res); - } - - final ITree res = curChild.next(); - //System.out.println("\t\tTRACE: adding node " + res + " to children"); - postChildren.add(res); - - return flushYields(res); - } -} -- cgit v1.2.3