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Diffstat (limited to 'jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/NullList.java')
-rw-r--r--jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/NullList.java153
1 files changed, 0 insertions, 153 deletions
diff --git a/jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/NullList.java b/jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/NullList.java
deleted file mode 100644
index a419b5e8f9..0000000000
--- a/jpa/plugins/org.eclipse.jpt.utility/src/org/eclipse/jpt/utility/internal/NullList.java
+++ /dev/null
@@ -1,153 +0,0 @@
-/*******************************************************************************
- * Copyright (c) 2008, 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;
-
-import java.io.Serializable;
-import java.util.Collection;
-import java.util.Iterator;
-import java.util.List;
-import java.util.ListIterator;
-import org.eclipse.jpt.utility.internal.iterators.EmptyIterator;
-import org.eclipse.jpt.utility.internal.iterators.EmptyListIterator;
-
-/**
- * A "null" list is a bit different from an "empty" list: it allows clients to
- * add/remove elements to/from it but never changes. This is useful
- * for passing to methods that require a "collecting parameter" but the
- * client will ignore the resulting "collection".
- */
-public final class NullList<E>
- implements List<E>, Serializable
-{
-
- // singleton
- @SuppressWarnings("unchecked")
- private static final NullList INSTANCE = new NullList();
-
- /**
- * Return the singleton.
- */
- @SuppressWarnings("unchecked")
- public static <E> List<E> instance() {
- return INSTANCE;
- }
-
- /**
- * Ensure single instance.
- */
- private NullList() {
- super();
- }
-
- public boolean add(E o) {
- return false; // the list did not change
- }
-
- public void add(int index, E element) {
- // ignore
- }
-
- public boolean addAll(Collection<? extends E> c) {
- return false; // the list did not change
- }
-
- public boolean addAll(int index, Collection<? extends E> c) {
- return false; // the list did not change
- }
-
- public void clear() {
- // ignore
- }
-
- public boolean contains(Object o) {
- return false;
- }
-
- public boolean containsAll(Collection<?> c) {
- return c.isEmpty();
- }
-
- public E get(int index) {
- throw new IndexOutOfBoundsException("Index: " + index + ", Size: 0"); //$NON-NLS-1$ //$NON-NLS-2$
- }
-
- public int indexOf(Object o) {
- return -1;
- }
-
- public boolean isEmpty() {
- return true;
- }
-
- public Iterator<E> iterator() {
- return EmptyIterator.instance();
- }
-
- public int lastIndexOf(Object o) {
- return -1;
- }
-
- public ListIterator<E> listIterator() {
- return EmptyListIterator.instance();
- }
-
- public ListIterator<E> listIterator(int index) {
- return EmptyListIterator.instance();
- }
-
- public boolean remove(Object o) {
- return false; // the list did not change
- }
-
- public E remove(int index) {
- throw new IndexOutOfBoundsException("Index: " + index + ", Size: 0"); //$NON-NLS-1$ //$NON-NLS-2$
- }
-
- public boolean removeAll(Collection<?> c) {
- return false; // the list did not change
- }
-
- public boolean retainAll(Collection<?> c) {
- return false; // the list did not change
- }
-
- public E set(int index, E element) {
- throw new IndexOutOfBoundsException("Index: " + index + ", Size: 0"); //$NON-NLS-1$ //$NON-NLS-2$
- }
-
- public int size() {
- return 0;
- }
-
- public List<E> subList(int fromIndex, int toIndex) {
- return this;
- }
-
- private static final Object[] EMPTY_OBJECT_ARRAY = new Object[0];
- public Object[] toArray() {
- return EMPTY_OBJECT_ARRAY;
- }
-
- public <T> T[] toArray(T[] a) {
- return a;
- }
-
- @Override
- public String toString() {
- return StringTools.buildToStringFor(this);
- }
-
- private static final long serialVersionUID = 1L;
- private Object readResolve() {
- // replace this object with the singleton
- return INSTANCE;
- }
-
-}

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