Map的两种遍历方式

Map<String,String> map = new HashMap<String,String> ();map.put("1", "a");map.put("2", "b");map.put("3", "c");//第一种遍历方式：返回set视图Set<Map.Entry<String, String>> entryseSet=map.entrySet();for (Map.Entry<String, String> entry:entryseSet) {    System.out.println(entry.getKey()+","+entry.getValue());}

//第二种遍历方式：返回键的set视图Iterator iterator = map.keySet().iterator(); while (iterator.hasNext()) {     String key = (String) iterator.next();     String value = map.get(key);     System.out.println(key+"=======>"+value);}