- /*
- * Copyright 2003-2004 The Apache Software Foundation
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
- package org.apache.commons.collections.collection;
-
- import java.util.Collection;
- import java.util.Iterator;
-
- import org.apache.commons.collections.BoundedCollection;
- import org.apache.commons.collections.iterators.UnmodifiableIterator;
-
- /**
- * <code>UnmodifiableBoundedCollection</code> decorates another
- * <code>BoundedCollection</code> to ensure it can't be altered.
- * <p>
- * If a BoundedCollection is first wrapped in some other collection decorator,
- * such as synchronized or predicated, the BoundedCollection methods are no
- * longer accessible.
- * The factory on this class will attempt to retrieve the bounded nature by
- * examining the package scope variables.
- * <p>
- * This class is Serializable from Commons Collections 3.1.
- *
- * @since Commons Collections 3.0
- * @version $Revision: 1.10 $ $Date: 2004/06/03 22:02:13 $
- *
- * @author Stephen Colebourne
- */
- public final class UnmodifiableBoundedCollection
- extends AbstractSerializableCollectionDecorator
- implements BoundedCollection {
-
- /** Serialization version */
- private static final long serialVersionUID = -7112672385450340330L;
-
- /**
- * Factory method to create an unmodifiable bounded collection.
- *
- * @param coll the <code>BoundedCollection</code> to decorate, must not be null
- * @return a new unmodifiable bounded collection
- * @throws IllegalArgumentException if bag is null
- */
- public static BoundedCollection decorate(BoundedCollection coll) {
- return new UnmodifiableBoundedCollection(coll);
- }
-
- /**
- * Factory method to create an unmodifiable bounded collection.
- * <p>
- * This method is capable of drilling down through up to 1000 other decorators
- * to find a suitable BoundedCollection.
- *
- * @param coll the <code>BoundedCollection</code> to decorate, must not be null
- * @return a new unmodifiable bounded collection
- * @throws IllegalArgumentException if bag is null
- */
- public static BoundedCollection decorateUsing(Collection coll) {
- if (coll == null) {
- throw new IllegalArgumentException("The collection must not be null");
- }
-
- // handle decorators
- for (int i = 0; i < 1000; i++) { // counter to prevent infinite looping
- if (coll instanceof BoundedCollection) {
- break; // normal loop exit
- } else if (coll instanceof AbstractCollectionDecorator) {
- coll = ((AbstractCollectionDecorator) coll).collection;
- } else if (coll instanceof SynchronizedCollection) {
- coll = ((SynchronizedCollection) coll).collection;
- } else {
- break; // normal loop exit
- }
- }
-
- if (coll instanceof BoundedCollection == false) {
- throw new IllegalArgumentException("The collection is not a bounded collection");
- }
- return new UnmodifiableBoundedCollection((BoundedCollection) coll);
- }
-
- /**
- * Constructor that wraps (not copies).
- *
- * @param coll the collection to decorate, must not be null
- * @throws IllegalArgumentException if coll is null
- */
- private UnmodifiableBoundedCollection(BoundedCollection coll) {
- super(coll);
- }
-
- //-----------------------------------------------------------------------
- public Iterator iterator() {
- return UnmodifiableIterator.decorate(getCollection().iterator());
- }
-
- public boolean add(Object object) {
- throw new UnsupportedOperationException();
- }
-
- public boolean addAll(Collection coll) {
- throw new UnsupportedOperationException();
- }
-
- public void clear() {
- throw new UnsupportedOperationException();
- }
-
- public boolean remove(Object object) {
- throw new UnsupportedOperationException();
- }
-
- public boolean removeAll(Collection coll) {
- throw new UnsupportedOperationException();
- }
-
- public boolean retainAll(Collection coll) {
- throw new UnsupportedOperationException();
- }
-
- //-----------------------------------------------------------------------
- public boolean isFull() {
- return ((BoundedCollection) collection).isFull();
- }
-
- public int maxSize() {
- return ((BoundedCollection) collection).maxSize();
- }
-
- }