java物件與json物件之間的轉換
阿新 • • 發佈:2018-12-12
1.簡單的解析json字串
首先將json字串轉換為json物件,然後再解析json物件,過程如下。JSONObject jsonObject = JSONObject.fromObject(jsonStr);
根據json中的鍵得到它的值
String name = jsonObject.getString("name");
int num = jsonObject.getInt("num");
String sex = jsonObject.getString("sex");
int age = jsonObject.getInt("age");
2.將json字串轉換為java物件
JSONObject obj = new JSONObject().fromObject(jsonStr);//將json字串轉換為json物件
將json物件轉換為java物件
Person jb = (Person)JSONObject.toBean(obj,Person.class);//將建json物件轉換為Person物件
3.將java物件轉換為json字串
先將java物件轉換為json物件,在將json物件轉換為json字串JSONObject json = JSONObject.fromObject(obj);//將java物件轉換為json物件
String str = json.toString();//將json物件轉換為字串
完整程式碼如下:
package baz.parse;
import java.util.ArrayList;
import java.util.List;
import net.sf.json.JSON;
import net.sf.json.JSONArray;
import net.sf.json.JSONObject;
import net.sf.json.JSONSerializer;
import baz.bean.Person;
public class ParseJson {
private String jsonStr;
public ParseJson() {
}
public ParseJson(String str){
this.jsonStr = str;
}
/**
* 解析json字串
*/
public void parse(){
JSONObject jsonObject = JSONObject.fromObject(jsonStr);
String name = jsonObject.getString("name");
int num = jsonObject.getInt("num");
String sex = jsonObject.getString("sex");
int age = jsonObject.getInt("age");
System.out.println(name + " " + num + " " + sex + " " + age);
}
//將json字串轉換為java物件
public Person JSON2Object(){
//接收{}物件,此處接收陣列物件會有異常
if(jsonStr.indexOf("[") != -1){
jsonStr = jsonStr.replace("[", "");
}
if(jsonStr.indexOf("]") != -1){
jsonStr = jsonStr.replace("]", "");
}
JSONObject obj = new JSONObject().fromObject(jsonStr);//將json字串轉換為json物件
Person jb = (Person)JSONObject.toBean(obj,Person.class);//將建json物件轉換為Person物件
return jb;//返回一個Person物件
}
}
package baz.bean;
public class Person {
private String name;
private int num;
private String sex;
private int age;
public Person() {
// TODO Auto-generated constructor stub
}
public Person(String name, int num, String sex, int age) {
super();
this.name = name;
this.num = num;
this.sex = sex;
this.age = age;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getNum() {
return num;
}
public void setNum(int num) {
this.num = num;
}
public String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
}
將java物件轉換為json字串
package baz.cons;
import net.sf.json.JSONObject;
/**
* 將java物件轉換為json字串
* @author Administrator
*
*/
public class ConsJson {
public ConsJson() {
// TODO Auto-generated constructor stub
}
public String Object2Json(Object obj){
JSONObject json = JSONObject.fromObject(obj);//將java物件轉換為json物件
String str = json.toString();//將json物件轉換為字串
return str;
}
}
測試類:
package baz.test;
import java.util.List;
import baz.bean.Person;
import baz.cons.ConsJson;
import baz.parse.ParseJson;
public class Test {
public static void main(String[] args) {
//將字串轉換為json物件,然後根據建得到相應的值
ParseJson pj = new ParseJson("{\"name\":\"gu\",\"num\":123456,\"sex\":\"male\",\"age\":24}");
pj.parse();
//將一個json字串轉換為java物件
Person p = pj.JSON2Object();
System.out.println("Name:" + p.getName());
System.out.println("Num:" + p.getNum());
System.out.println("Sex:" + p.getSex());
System.out.println("age:" + p.getAge());
//將一個java物件轉換為Json字串
Person p1 = new Person("gu1",123,"male",23);
ConsJson cj = new ConsJson();
String str1 = cj.Object2Json(p1);
System.out.println(str1);
}
}
測試輸出如下:gu 123456 male 24
Name:gu
Num:123456
Sex:male
age:24
{"age":23,"name":"gu1","num":123,"sex":"male"}
這只是最簡單使用方法,其他的使用我會在後期中更新。