public Object putIfAbsent(String name, Object obj)
  {
    if (obj == null)
      throw new NullPointerException();

    if (_attributes == null)
      _attributes = new ConcurrentHashMap<String,Object>(8);

    return _attributes.putIfAbsent(name, obj);
  }
public Object putIfAbsent ( String name , Object obj ) { if ( obj == null ) throw new NullPointerException ( ) ; if ( _attributes == null ) _attributes = new ConcurrentHashMap < String , Object > ( 8 ) ; return _attributes . putIfAbsent ( name , obj ) ; }
Sets the named attributes