java map类型转换成string类型

Map<String, String> map = new HashMap<String, String>();
map.put("key1", "value1");
map.put("key2", "value2");
map.put("key3", "value3");
System.out.println(map.toString());

执行结果：

{key1=value1, key2=value2, key3=value3}