public void putAll(Map m){
  Set keys=m.keySet();
  for (Iterator iter=keys.iterator(); iter.hasNext(); ) {
    Object key=iter.next();
    put(key,m.get(key));
  }
}

public void putAll ( Map m ) { Set keys = m . keySet ( ) ; for ( Iterator iter = keys . iterator ( ) ; iter . hasNext ( ) ; ) { Object key = iter . next ( ) ; put ( key , m . get ( key ) ) ; } }
puts all the elements in the map to this map .
