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Diffstat (limited to 'common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/iterators/ChainIterator.java')
-rw-r--r--common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/iterators/ChainIterator.java159
1 files changed, 0 insertions, 159 deletions
diff --git a/common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/iterators/ChainIterator.java b/common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/iterators/ChainIterator.java
deleted file mode 100644
index baf6710cb7..0000000000
--- a/common/plugins/org.eclipse.jpt.common.utility/src/org/eclipse/jpt/common/utility/internal/iterators/ChainIterator.java
+++ /dev/null
@@ -1,159 +0,0 @@
-/*******************************************************************************
- * Copyright (c) 2005, 2010 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.common.utility.internal.iterators;
-
-import java.util.Iterator;
-import java.util.NoSuchElementException;
-import org.eclipse.jpt.common.utility.internal.StringTools;
-
-/**
- * A <code>ChainIterator</code> provides a pluggable {@link Iterator}
- * that loops over a chain of arbitrarily linked objects. The chain
- * should be null-terminated (i.e. a call to the {@link #nextLink(Object)}
- * method should return <code>null</code> when it is passed the last
- * link of the chain).
- * To use, supply a starting link and supply a {@link Linker} or
- * subclass <code>ChainIterator</code> and override the
- * {@link #nextLink(Object)} method.
- * The starting link will be the first object returned by the iterator.
- * If the starting link is <code>null</code>, the iterator will be empty.
- * Note this iterator does not support <code>null</code> elements.
- *
- * @param <E> the type of elements returned by the iterator
- *
- * @see org.eclipse.jpt.common.utility.internal.iterables.ChainIterable
- */
-public class ChainIterator<E>
- implements Iterator<E>
-{
- private E nextLink;
- private final Linker<E> linker;
-
-
- /**
- * Construct an iterator with the specified starting link
- * and a disabled linker.
- * Use this constructor if you want to override the
- * {@link #nextLink(Object)} method instead of building
- * a {@link Linker}.
- */
- public ChainIterator(E startLink) {
- this(startLink, Linker.Disabled.<E>instance());
- }
-
- /**
- * Construct an iterator with the specified starting link
- * and linker.
- */
- public ChainIterator(E startLink, Linker<E> linker) {
- super();
- this.nextLink = startLink;
- this.linker = linker;
- }
-
- public boolean hasNext() {
- return this.nextLink != null;
- }
-
- public E next() {
- if (this.nextLink == null) {
- throw new NoSuchElementException();
- }
- E result = this.nextLink;
- this.nextLink = this.nextLink(this.nextLink);
- return result;
- }
-
- public void remove() {
- throw new UnsupportedOperationException();
- }
-
- /**
- * Return the next link in the chain; null if there are no more links.
- */
- protected E nextLink(E currentLink) {
- return this.linker.nextLink(currentLink);
- }
-
- @Override
- public String toString() {
- return StringTools.buildToStringFor(this, this.nextLink);
- }
-
-
- //********** member interface **********
-
- /**
- * Used by {@link ChainIterator} to link
- * the elements in the chain.
- */
- public interface Linker<T> {
-
- /**
- * Return the next link in the chain; null if there are no more links.
- */
- T nextLink(T currentLink);
-
-
- final class Null<S> implements Linker<S> {
- @SuppressWarnings("rawtypes")
- public static final Linker INSTANCE = new Null();
- @SuppressWarnings("unchecked")
- public static <R> Linker<R> instance() {
- return INSTANCE;
- }
- // ensure single instance
- private Null() {
- super();
- }
- // simply return null, indicating the chain is ended
- public S nextLink(S currentLink) {
- return null;
- }
- @Override
- public String toString() {
- return "ChainIterator.Linker.Null"; //$NON-NLS-1$
- }
- private static final long serialVersionUID = 1L;
- private Object readResolve() {
- // replace this object with the singleton
- return INSTANCE;
- }
- }
-
- final class Disabled<S> implements Linker<S> {
- @SuppressWarnings("rawtypes")
- public static final Linker INSTANCE = new Disabled();
- @SuppressWarnings("unchecked")
- public static <R> Linker<R> instance() {
- return INSTANCE;
- }
- // ensure single instance
- private Disabled() {
- super();
- }
- // throw an exception
- public S nextLink(S currentLink) {
- throw new UnsupportedOperationException(); // ChainIterator.nextLink(Object) was not implemented
- }
- @Override
- public String toString() {
- return "ChainIterator.Linker.Disabled"; //$NON-NLS-1$
- }
- private static final long serialVersionUID = 1L;
- private Object readResolve() {
- // replace this object with the singleton
- return INSTANCE;
- }
- }
-
- }
-
-}

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