json与对象，集合之间的相互转换

工具工具

创建时间:2019-01-07 18:42

阅读:

// 对象转json
private ObjectMapper mapper = new ObjectMapper();
@Test
public void testJson() throws JsonProcessingException {
User user = new User();
user.setId(8L);
user.setAge(21);
user.setName(“柳岩”);
user.setUserName(“liuyan”);
// 序列化
String json = mapper.writeValueAsString(user);
System.out.println(“json = “ + json);
}

// json转对象
private ObjectMapper mapper = new ObjectMapper();
@Test
public void testJson() throws IOException {
User user = new User();
user.setId(8L);
user.setAge(21);
user.setName(“柳岩”);
user.setUserName(“liuyan”);
// 序列化
String json = mapper.writeValueAsString(user);

// 反序列化，接收两个参数：json数据，反序列化的目标类字节码
User result = mapper.readValue(json, User.class);
System.out.println("result = " + result);

}

// json转集合
private ObjectMapper mapper = new ObjectMapper();
@Test
public void testJson() throws IOException {
User user = new User();
user.setId(8L);
user.setAge(21);
user.setName(“柳岩”);
user.setUserName(“liuyan”);

// 序列化,得到对象集合的json字符串
String json = mapper.writeValueAsString(Arrays.asList(user, user));

// 反序列化，接收两个参数：json数据，反序列化的目标类字节码
List<User> users = mapper.readValue(json, mapper.getTypeFactory().constructCollectionType(List.class, User.class));
for (User u : users) {
    System.out.println("u = " + u);
}

}

//json转任意复杂类型

private ObjectMapper mapper = new ObjectMapper();
@Test
public void testJson() throws IOException {
User user = new User();
user.setId(8L);
user.setAge(21);
user.setName(“柳岩”);
user.setUserName(“liuyan”);

// 序列化,得到对象集合的json字符串
String json = mapper.writeValueAsString(Arrays.asList(user, user));

// 反序列化，接收两个参数：json数据，反序列化的目标类字节码
List<User> users = mapper.readValue(json, new TypeReference<List<User>>(){});
for (User u : users) {
    System.out.println("u = " + u);
}

}

转载请注明来源，欢迎对文章中的引用来源进行考证，欢迎指出任何有错误或不够清晰的表达。可以在下面评论区评论，也可以邮件至 591235401@qq.com