| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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.collections4.list; |
| |
| import java.util.Collection; |
| import java.util.Iterator; |
| import java.util.List; |
| import java.util.ListIterator; |
| |
| import org.apache.commons.collections4.BoundedCollection; |
| import org.apache.commons.collections4.iterators.AbstractListIteratorDecorator; |
| import org.apache.commons.collections4.iterators.UnmodifiableIterator; |
| |
| /** |
| * Decorates another <code>List</code> to fix the size preventing add/remove. |
| * <p> |
| * The add, remove, clear and retain operations are unsupported. |
| * The set method is allowed (as it doesn't change the list size). |
| * <p> |
| * This class is Serializable from Commons Collections 3.1. |
| * |
| * @since 3.0 |
| * @version $Id$ |
| */ |
| public class FixedSizeList<E> |
| extends AbstractSerializableListDecorator<E> |
| implements BoundedCollection<E> { |
| |
| /** Serialization version */ |
| private static final long serialVersionUID = -2218010673611160319L; |
| |
| /** |
| * Factory method to create a fixed size list. |
| * |
| * @param <E> the type of the elements in the list |
| * @param list the list to decorate, must not be null |
| * @return a new fixed size list |
| * @throws NullPointerException if list is null |
| * @since 4.0 |
| */ |
| public static <E> FixedSizeList<E> fixedSizeList(final List<E> list) { |
| return new FixedSizeList<E>(list); |
| } |
| |
| //----------------------------------------------------------------------- |
| /** |
| * Constructor that wraps (not copies). |
| * |
| * @param list the list to decorate, must not be null |
| * @throws NullPointerException if list is null |
| */ |
| protected FixedSizeList(final List<E> list) { |
| super(list); |
| } |
| |
| //----------------------------------------------------------------------- |
| @Override |
| public boolean add(final E object) { |
| throw new UnsupportedOperationException("List is fixed size"); |
| } |
| |
| @Override |
| public void add(final int index, final E object) { |
| throw new UnsupportedOperationException("List is fixed size"); |
| } |
| |
| @Override |
| public boolean addAll(final Collection<? extends E> coll) { |
| throw new UnsupportedOperationException("List is fixed size"); |
| } |
| |
| @Override |
| public boolean addAll(final int index, final Collection<? extends E> coll) { |
| throw new UnsupportedOperationException("List is fixed size"); |
| } |
| |
| @Override |
| public void clear() { |
| throw new UnsupportedOperationException("List is fixed size"); |
| } |
| |
| @Override |
| public E get(final int index) { |
| return decorated().get(index); |
| } |
| |
| @Override |
| public int indexOf(final Object object) { |
| return decorated().indexOf(object); |
| } |
| |
| @Override |
| public Iterator<E> iterator() { |
| return UnmodifiableIterator.unmodifiableIterator(decorated().iterator()); |
| } |
| |
| @Override |
| public int lastIndexOf(final Object object) { |
| return decorated().lastIndexOf(object); |
| } |
| |
| @Override |
| public ListIterator<E> listIterator() { |
| return new FixedSizeListIterator(decorated().listIterator(0)); |
| } |
| |
| @Override |
| public ListIterator<E> listIterator(final int index) { |
| return new FixedSizeListIterator(decorated().listIterator(index)); |
| } |
| |
| @Override |
| public E remove(final int index) { |
| throw new UnsupportedOperationException("List is fixed size"); |
| } |
| |
| @Override |
| public boolean remove(final Object object) { |
| throw new UnsupportedOperationException("List is fixed size"); |
| } |
| |
| @Override |
| public boolean removeAll(final Collection<?> coll) { |
| throw new UnsupportedOperationException("List is fixed size"); |
| } |
| |
| @Override |
| public boolean retainAll(final Collection<?> coll) { |
| throw new UnsupportedOperationException("List is fixed size"); |
| } |
| |
| @Override |
| public E set(final int index, final E object) { |
| return decorated().set(index, object); |
| } |
| |
| @Override |
| public List<E> subList(final int fromIndex, final int toIndex) { |
| final List<E> sub = decorated().subList(fromIndex, toIndex); |
| return new FixedSizeList<E>(sub); |
| } |
| |
| /** |
| * List iterator that only permits changes via set() |
| */ |
| private class FixedSizeListIterator extends AbstractListIteratorDecorator<E> { |
| protected FixedSizeListIterator(final ListIterator<E> iterator) { |
| super(iterator); |
| } |
| @Override |
| public void remove() { |
| throw new UnsupportedOperationException("List is fixed size"); |
| } |
| @Override |
| public void add(final Object object) { |
| throw new UnsupportedOperationException("List is fixed size"); |
| } |
| } |
| |
| public boolean isFull() { |
| return true; |
| } |
| |
| public int maxSize() { |
| return size(); |
| } |
| |
| } |