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 2013-2016 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 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(K key, 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(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(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();
}
}
