Code example for WeakHashMap

Methods: put

0
		map = new WeakHashMap<E, Object>();
	} 
 
	@Override 
    public boolean add(E key) {
		return map.put(key, placeholder) == null;
	} 
 
	@Override 
    public void clear() { 
		map.clear();
	} 
 
	@Override 
    public boolean contains(Object key) {
		return map.containsKey(key);
	} 
 
	@Override 
    public boolean containsAll(Collection<?> arg0) {
		return map.keySet().containsAll(arg0);