JSON字符串中获取一个特定字段的值
- 一、方式一，引用gson工具
- 二、方式二，使用jackson
- 三、方式三，使用jackson转换Object
- 四、方式四，使用hutool，获取报文数组数据
一、方式一，引用gson工具
测试报文：
{
"account":"zhangsan",
"password":"123456"
}
引入pom
<!-- https://mvnrepository.com/artifact/com.google.code.gson/gson -->
<dependency>
<groupId>com.google.code.gson</groupId>
<artifactId>gson</artifactId>
<version>2.6.2</version>
</dependency>
代码
package com;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;
public class Test {
public static void main(String[] args) {
String json = "{\n" +
"\t\"account\":\"zhangsan\",\n" +
"\t\"password\":\"123456\"\n" +
"}";
JsonParser jsonParser = new JsonParser();
JsonElement jsonElement = jsonParser.parse(json);
JsonObject jsonObject = jsonElement.getAsJsonObject();
String fieldValue = jsonObject.get("account").getAsString();
System.out.println(fieldValue);
}
}
二、方式二，使用jackson
测试报文：
{
"account":"zhangsan",
"password":"123456",
"flag":"true"
}
代码
package com;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
public class Test {
public static void main(String[] args) throws JsonProcessingException {
String json = "{\n" +
"\t\"account\":\"zhangsan\",\n" +
"\t\"password\":\"123456\",\n" +
"\t\"flag\":\"true\"\n" +
"}";
ObjectMapper objectMapper = new ObjectMapper();
JsonNode jsonNode = objectMapper.readTree(json);
String account = jsonNode.get("account").asText();
int password = jsonNode.get("password").asInt();
boolean flag = jsonNode.get("flag").asBoolean();
System.out.println(account);
System.out.println(password);
System.out.println(flag);
}
}
三、方式三，使用jackson转换Object
测试报文：
{
"account":"zhangsan",
"password":"123456"
}
代码
package com;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
public class Test {
public static void main(String[] args) throws JsonProcessingException {
String json = "{\n" +
"\t\"account\":\"zhangsan\",\n" +
"\t\"password\":\"123456\"\n" +
"}";
ObjectMapper objectMapper = new ObjectMapper();
Login login = objectMapper.readValue(json, Test.Login.class);
System.out.println(login.toString());
}
public static class Login{
private String account;
private String password;
public String getAccount() {
return account;
}
public void setAccount(String account) {
this.account = account;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
@Override
public String toString() {
return "Login{" +
"account='" + account + '\'' +
", password='" + password + '\'' +
'}';
}
}
}
四、方式四，使用hutool，获取报文数组数据
测试报文：
{
"code":"0",
"message":"",
"data":[{
"account":"zhangsan",
"password":"123456"
}]
}
引入pom
<dependency>
<groupId>cn.hutool</groupId>
<artifactId>hutool-all</artifactId>
<version>4.1.19</version>
</dependency>
代码
package com;
import cn.hutool.json.JSONArray;
import cn.hutool.json.JSONObject;
import com.fasterxml.jackson.core.JsonProcessingException;
public class Test {
public static void main(String[] args) throws JsonProcessingException {
String json = "{\n" +
"\t\"code\":\"0\",\n" +
"\t\"message\":\"\",\n" +
"\t\"data\":[{\n" +
"\t\t\"account\":\"zhangsan\",\n" +
"\t\t\"password\":\"123456\"\n" +
"\t}]\n" +
"}";
JSONObject jsonObject = new JSONObject(json);
JSONArray jsonArray = jsonObject.getJSONArray("data");
JSONObject resultObject = jsonArray.getJSONObject(0);
String account = resultObject.getStr("account");
System.out.println(account);
}
}
OK，就这些吧。
有什么不对的还望指正，书写不易，觉得有帮助就点个赞吧！☺☺☺
参考链接：https://www.cnblogs.com/xbinbin/p/17647956.html
