fastjson--Gson生成Json字符串，并且解析Json字符串生成对象

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json.jar地址下载点击打开链接

+++++++++++++++++++++++++++++先看fastjson的使用方法++++++++++++++++++++++++++++++++

Student

package com.example.fastjson;
public class Student {  private String name;  private int age;  /*** 默认的构造方法必须要写，不然是无法解析的*/public Student() {  }  public Student(String name,int age){  this.name = name;  this.age = age;  }  public int getAge() {  return age;  }  public void setAge(int age) {  this.age = age;  }  public String getName() {  return name;  }  public void setName(String name) {  this.name = name;  }  @Overridepublic String toString() {return "Student [name=" + name + ", age=" + age + "]";  }
}

Grade

package com.example.fastjson;
import java.util.ArrayList;
import java.util.List;public class Grade {  private String gradeName;  private List<Student> students = new ArrayList<Student>();  public Grade() {  }  public Grade(String gradeName) {  this.gradeName = gradeName;  }  public String getGradeName() {  return gradeName;  }  public void setGradeName(String gradeName) {  this.gradeName = gradeName;  }  public List<Student> getStudents() {  return students;  }  public void setStudents(List<Student> students) {  this.students = students;  }  }

MainActivity

package com.example.fastjson;import java.util.ArrayList;
import java.util.List;import android.app.Activity;
import android.os.Bundle;
import android.util.Log;import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.TypeReference;
import com.alibaba.fastjson.serializer.SimplePropertyPreFilter;public class MainActivity extends Activity {@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);/*** 1、1输出javaBean的json格式*/Student student = new Student("dandy",27);  String jsonStudent1 = JSON.toJSONString(student);  String jsonStudent2 = JSON.toJSONString(student,true);  //jsonStudent:{"age":27,"name":"dandy"}Log.i("TAG", "jsonStudent1 standard:"+jsonStudent1);Log.i("TAG", "jsonStudent2 true:"+jsonStudent2);/*** 1、2输出javaBean的特定属性json格式* new SimplePropertyPreFilter(实体类.class,"字段一","字段二"); */SimplePropertyPreFilter filter = new SimplePropertyPreFilter(Student.class,"name");  String jsonStudent = JSON.toJSONString(student,filter);  Log.i("TAG", "jsonStudent filter:"+jsonStudent);/*** 1、3输出复杂的javaBean(带集合的)*/Grade grade = new Grade("高一");  grade.getStudents().add(new Student("dandy",27));  grade.getStudents().add(new Student("Tabolt", 28));  String jsonGrade = JSON.toJSONString(grade);  Log.i("TAG", "jsonGrade:"+jsonGrade);/*** 2、1Json生成javaBean对象实例*/String json = JSON.toJSONString(new Student("Tabolt", 28));  Student studentBean = JSON.parseObject(json,Student.class);  Log.i("TAG", "studentBean:"+studentBean);/*** 2、2Json生成javaBean对象实例 集合*/List<Student> students = new ArrayList<Student>();  for(int i = 0;i < 5;i++){  Student studentFor = new Student("dandy_"+i,26+i);  students.add(studentFor);  }  String jsonFor = JSON.toJSONString(students);  List<Student> stus1 = JSON.parseArray(jsonFor, Student.class);List<Student> stus2 = JSON.parseObject(jsonFor,new TypeReference<List<Student>>(){});  for(Student stu:stus1){  Log.i("TAG", "studentBean:"+stu.toString());}  for(Student stu:stus2){  Log.i("TAG", "studentBean:"+stu.toString());}  }
}

log输出如下。。。

+++++++++++++++++++++++++++++先看Gson的使用方法++++++++++++++++++++++++++++++++

package com.example.gsondemo;import java.util.ArrayList;
import java.util.List;import android.app.Activity;
import android.os.Bundle;
import android.util.Log;import com.google.gson.Gson;
import com.google.gson.reflect.TypeToken;public class MainActivity extends Activity {@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);/*** 1、1gson解析对象*/Gson gson = new Gson();Student student = new Student("dandy", 27);String stuStr = gson.toJson(student);Log.i("TAG", "str:" + stuStr);/*** 1、2gson解析数组对象*/Grade grade = new Grade("高一");grade.getStudents().add(new Student("dandy", 27));grade.getStudents().add(new Student("Tabolt", 28));String str = gson.toJson(grade);Log.i("TAG", "str:" + str);/*** * 2、1 gson解析字符串为javaBean对象*/Student fromJson2Stu = gson.fromJson(stuStr, Student.class);Log.i("TAG", "fromJson2Stu-->" + fromJson2Stu.toString());/*** 2、2gson解析字符串为javaBean对象集合*/List<Student> students = new ArrayList<Student>();for (int i = 0; i < 5; i++) {Student studentFor = new Student("dandy_" + i, 26 + i);students.add(studentFor);}String jsonFor = gson.toJson(students);List<Student> fromJson2StuArr = gson.fromJson(jsonFor,new TypeToken<List<Student>>() {}.getType());for (int i = 0; i < fromJson2StuArr.size(); i++) {Student student2 = fromJson2StuArr.get(i);Log.i("TAG", "student2-->" + student2.toString());}}}