Java Map遍歴

2908 ワード

一般的な遍歴には4つの方法があります
//   :    ,    
  System.out.println("  Map.keySet  key value:");
  for (String key : map.keySet()) {
   System.out.println("key= "+ key + " and value= " + map.get(key));
  }

  //   
  System.out.println("  Map.entrySet  iterator  key value:");
  Iterator.Entry> it = map.entrySet().iterator();
  while (it.hasNext()) {
   Map.Entry entry = it.next();
   System.out.println("key= " + entry.getKey() + " and value= " + entry.getValue());
  }

  //   :  ,       
  System.out.println("  Map.entrySet  key value");
  for (Map.Entry entry : map.entrySet()) {
   System.out.println("key= " + entry.getKey() + " and value= " + entry.getValue());
  }

  //   
  System.out.println("  Map.values()     value,     key");
  for (String v : map.values()) {
   System.out.println("value= " + v);