package com.planet_ink.coffee_mud.core.collections; import java.util.ArrayList; import java.util.Collection; import java.util.Hashtable; import java.util.Iterator; import java.util.LinkedList; import java.util.List; import java.util.ListIterator; import java.util.Map; /* Copyright 2013-2019 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 OrderedMap<K,J> extends Hashtable<K,J> implements Iterable<J> { private static final long serialVersionUID = -6379440278237091571L; private volatile ArrayList<J> list = null; @SuppressWarnings("rawtypes" ) private static final Iterator empty=EmptyIterator.INSTANCE; @SuppressWarnings("unchecked") @Override public Iterator<J> iterator() { if(size()==0) return empty; return list.iterator(); } @SuppressWarnings("unchecked") @Override public synchronized J put(final K key, final J value) { final ArrayList<J> newList; if (list == null) { newList=new ArrayList<J>(0); newList.add(value); } else { if(containsKey(key)) { if((list.size()>0)&&(list.get(0)==value)) return value; } newList=(ArrayList<J>)list.clone(); if(containsKey(key)) newList.remove(value); if(newList.size()==0) newList.add(value); else newList.add(0, value); } list=newList; return super.put(key, value); } @Override public synchronized void putAll(final Map<? extends K, ? extends J> t) { for(final Map.Entry<? extends K,? extends J> i : t.entrySet()) put(i.getKey(),i.getValue()); } @Override public synchronized J remove(final Object key) { if(super.containsKey(key)) { @SuppressWarnings("unchecked") final ArrayList<J> newList=(ArrayList<J>)list.clone(); newList.remove(get(key)); list=newList; } return super.remove(key); } @Override public synchronized void clear() { list=null; super.clear(); } }