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Diffstat (limited to 'jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/iterators/TreeIterator.java')
-rw-r--r--jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/iterators/TreeIterator.java242
1 files changed, 0 insertions, 242 deletions
diff --git a/jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/iterators/TreeIterator.java b/jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/iterators/TreeIterator.java
deleted file mode 100644
index 2012de791d..0000000000
--- a/jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/iterators/TreeIterator.java
+++ /dev/null
@@ -1,242 +0,0 @@
-/*******************************************************************************
- * Copyright (c) 2005, 2009 Oracle. All rights reserved.
- * This program and the accompanying materials are made available under the
- * terms of the Eclipse Public License v1.0, which accompanies this distribution
- * and is available at http://www.eclipse.org/legal/epl-v10.html.
- *
- * Contributors:
- * Oracle - initial API and implementation
- ******************************************************************************/
-package org.eclipse.jpt.utility.internal.iterators;
-
-import java.util.Iterator;
-import java.util.LinkedList;
-import org.eclipse.jpt.utility.internal.StringTools;
-
-/**
- * A <code>TreeIterator</code> simplifies the traversal of a
- * tree of objects, where the objects' protocol(s) provides
- * a method for getting the immediate children of the given
- * node but does not provide a method for getting all the
- * descendants (children, grandchildren, etc.) of the given node.
- * <p>
- * To use, supply:<ul>
- * <li> either the root element of the tree or, if the tree has
- * multiple roots, an {@link Iterator} over the set of roots
- * <li> a {@link Midwife} that delivers the children
- * of each child
- * (alternatively, subclass <code>TreeIterator</code>
- * and override the {@link #children(Object)} method)
- * </ul>
- *
- * @param <E> the type of elements returned by the iterator
- */
-public class TreeIterator<E>
- implements Iterator<E>
-{
- private final LinkedList<Iterator<? extends E>> iterators;
- private final Midwife<E> midwife;
- private Iterator<? extends E> currentIterator;
-
-
- /**
- * Construct an iterator that returns the nodes of a tree
- * with the specified collection of roots
- * and a disabled midwife.
- * Use this constructor if you want to override the
- * {@link #children(Object)} method instead of building
- * a {@link Midwife}.
- */
- public TreeIterator(E... roots) {
- this(new ArrayIterator<E>(roots));
- }
-
- /**
- * Construct an iterator that returns the nodes of a tree
- * with the specified collection of roots
- * and a disabled midwife.
- * Use this constructor if you want to override the
- * {@link #children(Object)} method instead of building
- * a {@link Midwife}.
- */
- public TreeIterator(Iterable<? extends E> roots) {
- this(roots.iterator());
- }
-
- /**
- * Construct an iterator that returns the nodes of a tree
- * with the specified collection of roots
- * and a disabled midwife.
- * Use this constructor if you want to override the
- * {@link #children(Object)} method instead of building
- * a {@link Midwife}.
- */
- public TreeIterator(Iterator<? extends E> roots) {
- this(roots, Midwife.Disabled.<E>instance());
- }
-
- /**
- * Construct an iterator that returns the nodes of a tree
- * with the specified root and a disabled midwife.
- * Use this constructor if you want to override the
- * {@link #children(Object)} method instead of building
- * a {@link Midwife}.
- */
- public TreeIterator(E root) {
- this(root, Midwife.Disabled.<E>instance());
- }
-
- /**
- * Construct an iterator that returns the nodes of a tree
- * with the specified root and midwife.
- */
- public TreeIterator(E root, Midwife<E> midwife) {
- this(new SingleElementIterator<E>(root), midwife);
- }
-
- /**
- * Construct an iterator that returns the nodes of a tree
- * with the specified roots and midwife.
- */
- public TreeIterator(E[] roots, Midwife<E> midwife) {
- this(new ArrayIterator<E>(roots), midwife);
- }
-
- /**
- * Construct an iterator that returns the nodes of a tree
- * with the specified roots and midwife.
- */
- public TreeIterator(Iterable<? extends E> roots, Midwife<E> midwife) {
- this(roots.iterator(), midwife);
- }
-
- /**
- * Construct an iterator that returns the nodes of a tree
- * with the specified roots and midwife.
- */
- public TreeIterator(Iterator<? extends E> roots, Midwife<E> midwife) {
- super();
- this.currentIterator = roots;
- // use a LinkedList since we will be pulling off the front and adding to the end
- this.iterators = new LinkedList<Iterator<? extends E>>();
- this.midwife = midwife;
- }
-
- public boolean hasNext() {
- if (this.currentIterator.hasNext()) {
- return true;
- }
- for (Iterator<? extends E> iterator : this.iterators) {
- if (iterator.hasNext()) {
- return true;
- }
- }
- return false;
- }
-
- public E next() {
- if (this.currentIterator.hasNext()) {
- return this.nextInternal();
- }
- for (Iterator<Iterator<? extends E>> stream = this.iterators.iterator(); stream.hasNext(); ) {
- this.currentIterator = stream.next();
- if (this.currentIterator.hasNext()) {
- break;
- }
- stream.remove();
- }
- return this.nextInternal();
- }
-
- /**
- * Fetch the children of the next node before returning it.
- */
- private E nextInternal() {
- E next = this.currentIterator.next();
- this.iterators.add(this.children(next));
- return next;
- }
-
- public void remove() {
- this.currentIterator.remove();
- }
-
- /**
- * Return the immediate children of the specified object.
- * <p>
- * This method can be overridden by a subclass as an
- * alternative to building a {@link Midwife}.
- */
- protected Iterator<? extends E> children(E next) {
- return this.midwife.children(next);
- }
-
- @Override
- public String toString() {
- return StringTools.buildToStringFor(this, this.currentIterator);
- }
-
-
- //********** inner classes **********
-
- /**
- * Used by {@link TreeIterator} to retrieve
- * the immediate children of a node in the tree.
- */
- public interface Midwife<T> {
-
- /**
- * Return the immediate children of the specified object.
- */
- Iterator<? extends T> children(T o);
-
-
- final class Null<S> implements Midwife<S> {
- @SuppressWarnings("unchecked")
- public static final Midwife INSTANCE = new Null();
- @SuppressWarnings("unchecked")
- public static <R> Midwife<R> instance() {
- return INSTANCE;
- }
- // ensure single instance
- private Null() {
- super();
- }
- // return no neighbors
- public Iterator<S> children(S next) {
- return EmptyIterator.instance();
- }
- @Override
- public String toString() {
- return "TreeIterator.Midwife.Null"; //$NON-NLS-1$
- }
- }
-
- /**
- * The midwife used when the {@link TreeIterator#children(Object)}
- * method is overridden.
- */
- final class Disabled<S> implements Midwife<S> {
- @SuppressWarnings("unchecked")
- public static final Midwife INSTANCE = new Disabled();
- @SuppressWarnings("unchecked")
- public static <R> Midwife<R> instance() {
- return INSTANCE;
- }
- // ensure single instance
- private Disabled() {
- super();
- }
- // throw an exception
- public Iterator<S> children(S next) {
- throw new UnsupportedOperationException(); // TreeIterator.children(Object) was not implemented
- }
- @Override
- public String toString() {
- return "TreeIterator.Midwife.Disabled"; //$NON-NLS-1$
- }
- }
-
- }
-
-}

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