遍历 java map_Java Map 的三种遍历方式

第一种是遍历 map中键所对应的值

public static void work(Map map) {

Collection c = map.values();

Iterator it = c.iterator();

for (; it.hasNext();) {

System.out.println(it.next());

}

}

第二种是遍历 map中的 键 和 值

public static void workByKeySet(Map map) {

Set key = map.keySet();

for (Iterator it = key.iterator(); it.hasNext();) {

String s = (String) it.next();

System.out.println(map.get(s));

}

}

第三种和第二种差不多，但是比较灵活  public static void workByEntry(Map map) {         Set> set = map.entrySet();         for (Iterator> it = set.iterator(); it.hasNext();) {             Map.Entry entry = (Map.Entry) it.next();             System.out.println(entry.getKey() + "--->" + entry.getValue());         }     } }