package com.planet_ink.coffee_mud.core.collections; import java.lang.ref.WeakReference; import java.util.*; /* Copyright 2011-2016 Bo Zimmerman 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. */ public class ChameleonList<K> implements List<K>, SizedIterable<K> { private volatile List<K> list; private volatile Signaler<K> signaler; public static abstract class Signaler<K> { protected WeakReference<List<K>> oldReferenceListRef; public Signaler(final List<K> referenceList) { oldReferenceListRef = new WeakReference<List<K>>(referenceList); } public abstract void rebuild(final ChameleonList<K> me); public abstract boolean isDeprecated(); public final synchronized void possiblyChangeMe(final ChameleonList<K> me) { if(!isDeprecated()) return; rebuild(me); } } public ChameleonList(final List<K> l, final Signaler<K> signaler) { list=l; this.signaler = signaler; } public void changeMeInto(final ChameleonList<K> fromList) { this.list=fromList.list; this.signaler=fromList.signaler; } public Signaler<K> getSignaler() { return signaler;} @Override public boolean add(K arg0) { throw new java.lang.IllegalArgumentException(); } @Override public void add(int arg0, K arg1) { throw new java.lang.IllegalArgumentException(); } @Override public boolean addAll(Collection<? extends K> arg0) { throw new java.lang.IllegalArgumentException(); } @Override public boolean addAll(int arg0, Collection<? extends K> arg1) { throw new java.lang.IllegalArgumentException(); } @Override public void clear() { throw new java.lang.IllegalArgumentException(); } @Override public boolean contains(Object arg0) { signaler.possiblyChangeMe(this); return list.contains(arg0); } @Override public boolean containsAll(Collection<?> arg0) { signaler.possiblyChangeMe(this); return list.containsAll(arg0); } @Override public K get(int arg0) { signaler.possiblyChangeMe(this); return list.get(arg0); } @Override public int indexOf(Object arg0) { signaler.possiblyChangeMe(this); return list.indexOf(arg0); } @Override public boolean isEmpty() { signaler.possiblyChangeMe(this); return list.isEmpty(); } @Override public Iterator<K> iterator() { signaler.possiblyChangeMe(this); return new ReadOnlyIterator<K>(list.iterator()); } @Override public int lastIndexOf(Object arg0) { signaler.possiblyChangeMe(this); return list.lastIndexOf(arg0); } @Override public ListIterator<K> listIterator() { signaler.possiblyChangeMe(this); return new ReadOnlyListIterator<K>(list.listIterator()); } @Override public ListIterator<K> listIterator(int arg0) { signaler.possiblyChangeMe(this); return new ReadOnlyListIterator<K>(list.listIterator(arg0)); } @Override public boolean remove(Object arg0) { throw new java.lang.IllegalArgumentException(); } @Override public K remove(int arg0) { throw new java.lang.IllegalArgumentException(); } @Override public boolean removeAll(Collection<?> arg0) { throw new java.lang.IllegalArgumentException(); } @Override public boolean retainAll(Collection<?> arg0) { throw new java.lang.IllegalArgumentException(); } @Override public K set(int arg0, K arg1) { throw new java.lang.IllegalArgumentException(); } @Override public int size() { signaler.possiblyChangeMe(this); return list.size(); } @Override public List<K> subList(int arg0, int arg1) { signaler.possiblyChangeMe(this); return new ReadOnlyList<K>(list.subList(arg0,arg1)); } @Override public Object[] toArray() { signaler.possiblyChangeMe(this); return list.toArray(); } @Override public <T> T[] toArray(T[] arg0) { signaler.possiblyChangeMe(this); return list.toArray(arg0); } }