public Hashtable(Map<? extends K,? extends V> t){
  this(Math.max(2 * t.size(),11),0.75f);
  putAll(t);
}

public Hashtable ( Map < ? extends K , ? extends V > t ) { this ( Math . max ( 2 * t . size ( ) , 11 ) , 0.75f ) ; putAll ( t ) ; }
constructs a new hashtable with the same mappings as the given map . the hashtable is created with an initial capacity sufficient to hold the mappings in the given map and a default load factor ( 0 . 75 ) .
