java对象与json对象间的相互转换的方法

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");

JSONObject obj = new JSONObject().fromObject(jsonStr);
//将json字符串转换为json对象

Person jb = (Person)JSONObject.toBean(obj,Person.class);
//将建json对象转换为Person对象

JSONObject json = JSONObject.fromObject(obj);

//将java对象转换为json对象
String str = json.toString();//将json对象转换为字符串

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字符串 
   */ 
  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); 
  } 
  //将json字符串转换为java对象 
  public Person JSON2Object(){ 
    //接收{}对象，此处接收数组对象会有异常 
    if(jsonStr.indexOf("[") != -1){ 
      jsonStr = jsonStr.replace("[", ""); 
    } 
    if(jsonStr.indexOf("]") != -1){ 
      jsonStr = jsonStr.replace("]", ""); 
    } 
    JSONObject obj = new JSONObject().fromObject(jsonStr);//将json字符串转换为json对象 
    Person jb = (Person)JSONObject.toBean(obj,Person.class);//将建json对象转换为Person对象 
    return jb;//返回一个Person对象 
  } 
   
 
} 

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; 
  } 
   
} 

package baz.cons; 
 import net.sf.json.JSONObject; 
 /** 
 * 将java对象转换为json字符串 
 * @author Administrator 
 * 
 */ 
public class ConsJson { 
   
  public ConsJson() { 
    // TODO Auto-generated constructor stub 
  } 
   
  public String Object2Json(Object obj){ 
    JSONObject json = JSONObject.fromObject(obj);//将java对象转换为json对象 
    String str = json.toString();//将json对象转换为字符串 
     
    return str; 
  } 
} 

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) { 
     
    //将字符串转换为json对象，然后根据建得到相应的值 
    ParseJson pj = new ParseJson("{\"name\":\"gu\",\"num\":123456,\"sex\":\"male\",\"age\":24}"); 
    pj.parse(); 
     
    //将一个json字符串转换为java对象 
    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()); 
     
    //将一个java对象转换为Json字符串 
    Person p1 = new Person("gu1",123,"male",23); 
    ConsJson cj = new ConsJson(); 
    String str1 = cj.Object2Json(p1); 
    System.out.println(str1); 
     
  } 
 
} 

{"age":23,"name":"gu1","num":123,"sex":"male"}