public static void main(String[] args){ Map<String, String> map = new HashMap<String, String>(); map.put("id1", "wang"); map.put("id2", "sheng"); //方法一 Set<String> set = map.keySet(); for (String s:set) { System.out.println(s+","+map.get(s)); } //方法二 Set<Map.Entry<String, String>> entryseSet=map.entrySet(); for (Map.Entry<String, String> entry:entryseSet) { System.out.println(entry.getKey()+","+entry.getValue()); } }