fastjson生成和解析json数据

发布时间：2020-12-16 19:41:06 所属栏目：百科来源：网络整理

导读：本文讲解2点： 1. fastjson生成和解析json数据 (举例：4种常用类型:JavaBean,ListJavaBean,ListString,ListMapString,Object) 2.通过一个android程序测试fastjson的用法。 fastjson简介： Fastjson是一个Java语言编写的高性能功能完善的JSON库。fastjson采用

本文讲解2点：

1. fastjson生成和解析json数据

(举例：4种常用类型:JavaBean,List<JavaBean>,List<String>,List<Map<String,Object>)

2.通过一个android程序测试fastjson的用法。

fastjson简介：

Fastjson是一个Java语言编写的高性能功能完善的JSON库。fastjson采用独创的算法，将parse的速度提升到极致，超过所有json库，包括曾经号称最快的jackson。并且还超越了google的二进制协议protocol buf。Fastjson完全支持http://json.org的标准，也是官方网站收录的参考实现之一。支持各种JDK类型。包括基本类型、JavaBean、Collection、Map、Enum、泛型等。支持JDK 5、JDK 6、Android、阿里云手机等环境。

一. fastjson生成json字符串(JavaBean,Object>)

String jsonStrng = JSON.toJSONString(object);

二. fastjson 解析json字符串为四种类型

1. JavaBean

Person person = JSON.parSEObject(jsonString,Person.class);

2. List<JavaBean>

List<Person> listPerson =JSON.parseArray(jsonString,43)"> 3. List<String>

List<String> listString = JSON.parseArray(jsonString,String.class);

4. List<Map<String,Object>>

List<Map<String,Object>> listMap = JSON.parSEObject(jsonString,new TypeReference<List<Map<String,Object>>>(){}); (注意：此处可看出fastjson反射机制比gson更准确， id = 1001 通过fastjson反射仍是 id = 1001,而通过gson反射结果为 id =1001.0,参考前篇程序运行结果图GSON方式生成和解析json数据)

-----------------------------------------------------------------------------------------------------------------------------------------

程序运行结果：

1. 点击“解析Person数据”按钮

2. 点击“解析Persons数据按钮”

3.点击“解析listString数据”按钮

4.点击“解析listMap数据”按钮

--------------------------------------------------------------------------------------------------------------------------------------

客户端eclipse android工程目录（左边）服务器端myeclipse web工程（右边）

---------------------------------------------------------------------------------------------------------------------------------------

服务器端 fastjson_Project

1.FastJsonAction.java

[java] 
   view plain 
   copy 
    
   
 
   
 packagecom.fastjson.action;
 
importjava.io.IOException;
 importjava.io.PrintWriter;
 
importjavax.servlet.ServletException;
importjavax.servlet.http.HttpServlet;
importjavax.servlet.http.HttpServletRequest;
importjavax.servlet.http.HttpServletResponse;
importcom.fastjson.service.FastJsonService;
importcom.fastjson.tools.*;
publicclassFastJsonActionextendsHttpServlet{
 /**
 *Destructionoftheservlet.<br>
*/
voiddestroy(){
super.destroy();//Justputs"destroy"stringinlog
//Putyourcodehere
 }
*ThedoGetmethodoftheservlet.<br>
*
*Thismethodiscalledwhenaformhasitstagvaluemethodequalstoget.
*@paramrequesttherequestsendbytheclienttotheserver
*@paramresponsetheresponsesendbytheservertotheclient
*@throwsServletExceptionifanerroroccurred
*@throwsIOExceptionifanerroroccurred
*/
voiddoGet(HttpServletRequestrequest,HttpServletResponseresponse)
throwsServletException,IOException{
this.doPost(request,response);
 }
/**
*ThedoPostmethodoftheservlet.<br>
*
*Thismethodiscalledwhenaformhasitstagvaluemethodequalstopost.
*@paramrequesttherequestsendbytheclienttotheserver
*@paramresponsetheresponsesendbytheservertotheclient
*@throwsServletExceptionifanerroroccurred
*@throwsIOExceptionifanerroroccurred
voiddoPost(HttpServletRequestrequest,HttpServletResponseresponse)
 response.setContentType("text/html;charset=utf-8");
 request.setCharacterEncoding("utf-8");
 response.setCharacterEncoding("utf-8");
 Stringaction_flag=request.getParameter("action_flag");
 PrintWriterout=response.getWriter();
if("person".equals(action_flag)){
//Stringperson=GsonTools.creatJsonString(GsonService.getPerson());
 Stringperson=FastJsonTools.createJsonString(FastJsonService.getPerson());
 out.println(person);
 System.out.println(person);
 }elseif("persons".equals(action_flag)){
//Stringpersons=GsonTools.creatJsonString(GsonService.getListPersons());
 Stringpersons=FastJsonTools.createJsonString(FastJsonService.getListPersons());
 out.println(persons);
 System.out.println(persons);
 }if("listString".equals(action_flag)){
//StringlistString=GsonTools.creatJsonString(GsonService.getListString());
 StringlistString=FastJsonTools.createJsonString(FastJsonService.getListString());
 out.println(listString);
 System.out.println(listString);
if("listMap".equals(action_flag)){
//StringlistMap=GsonTools.creatJsonString(GsonService.getListMap());
 StringlistMap=FastJsonTools.createJsonString(FastJsonService.getListMap());
 out.println(listMap);
 System.out.println(listMap);
 System.out.println();
 out.flush();
 out.close();
*Initializationoftheservlet.<br>
*@throwsServletExceptionifanerroroccurs
voidinit()throwsServletException{
 }

2.FastJsonService.java

copy

com.fastjson.service;

importjava.util.ArrayList;
importjava.util.HashMap;
importjava.util.List;
importjava.util.Map;
importcom.fastjson.data.Person;
classFastJsonService{
staticPersongetPerson(){
Personperson=newPerson(1001,"刘德华","香港");
returnperson;
staticList<Person>getListPersons(){
List<Person>persons=newArrayList<Person>();
Personperson1="香港");
Personperson2=1002,"宋慧乔","韩国");
persons.add(person1);
persons.add(person2);
returnpersons;
staticList<String>getListString(){
List<String>list=newArrayList<String>();
list.add("美国");
list.add("中国");
list.add("俄罗斯");
returnlist;
staticList<java.util.Map<String,Object>>getListMap(){
List<java.util.Map<String,Object>>list=newArrayList<Map<String,Object>>();
java.util.Map<String,Object>map1=newHashMap<String,Object>();
map1.put("id",1001);
map1.put("name","刘德华");
map1.put("address",108); list-style:decimal-leading-zero outside; color:inherit; line-height:18px; margin:0px!important; padding:0px 3px 0px 10px!important"> java.util.Map<String,Object>map2= map2.put("id",0); background-color:inherit">1002);
map2.put("name","宋慧乔");
map2.put("address",248)"> list.add(map1);
list.add(map2);
returnlist;
}

3.FastJsonTools.java

copy

com.fastjson.tools;

importcom.alibaba.fastjson.*;
classFastJsonTools{
staticStringcreateJsonString(Objectobject){
StringjsonString="";
try{
jsonString=JSON.toJSONString(object);
catch(Exceptione){
//TODO:handleexception
returnjsonString;
4.Person.java

copy
1. classPerson{
2. privateintid;
3. privateStringname;
4. privateStringaddress;
5. publicPerson(){
6. //TODOAuto-generatedconstructorstub
7. intgetId(){
8. returnid;
9. voidsetId(intid){
10. this.id=id;
11. publicStringgetName(){
12. returnname;
13. voidsetName(Stringname){
14. this.name=name;
15. publicStringgetAddress(){
16. returnaddress;
17. voidsetAddress(Stringaddress){
18. this.address=address;
19. publicPerson(intid,Stringname,Stringaddress){
20. super();
21. this.id=id;
22. this.address=address;
23. @Override
24. publicStringtoString(){
25. return"Person[id="+id+",name="+name+",address="+address
26. +"]";
27. 5. TestFastJson.java
  
  copy
  1. importcom.fastjson.tools.FastJsonTools;
  2. classTestFastJson{
  3. *@paramargs
  4. staticvoidmain(String[]args){
  5. //TODOAuto-generatedmethodstub
  6. //Test1Person
  7. System.out.println("FastJson数据格式测试结果：n");
  8. //Test2persons
  9. StringlistPerson=FastJsonTools.createJsonString(FastJsonService.getListPersons());
  10. //Test3listString
  11. //Test4listMap
  12. StringlistMap=FastJsonTools.createJsonString(FastJsonService.getListMap());
  13. System.out.println("测试结果1："+person+"n");
  14. System.out.println("测试结果2："+listPerson+"n");
  15. System.out.println("测试结果3："+listString+"n");
  16. System.out.println("测试结果4："+listMap);
  17. 客户端：android_fastjson
    
    1.MainActivity.java
    
    copy
    1. importjava.io.ByteArrayOutputStream;
    2. importjava.io.IOException;
    3. importjava.io.InputStream;
    4. importjava.io.Serializable;
    5. importjava.net.HttpURLConnection;
    6. importjava.net.URL;
    7. importcom.alibaba.fastjson.JSON;
    8. importcom.alibaba.fastjson.TypeReference;
    9. importcom.gson.data.Person;
    10. importcom.gson.http.HttpUtils;
    11. importandroid.os.Bundle;
    12. importandroid.os.StrictMode;
    13. importandroid.annotation.SuppressLint;
    14. importandroid.app.Activity;
    15. importandroid.content.Intent;
    16. importandroid.view.View;
    17. importandroid.view.View.OnClickListener;
    18. importandroid.widget.Button;
    19. classMainActivityextendsActivityimplementsOnClickListener{
    20. privateButtonperson,persons,listString,listMap;
    21. @Override
    22. protectedvoidonCreate(BundlesavedInstanceState){
    23. super.onCreate(savedInstanceState);
    24. setContentView(R.layout.activity_main);
    25. closeStrictMode();//关闭严苛模式
    26. person=(Button)findViewById(R.id.person);
    27. persons=(Button)findViewById(R.id.persons);
    28. listString=(Button)findViewById(R.id.listString);
    29. listMap=(Button)findViewById(R.id.listMap);
    30. person.setOnClickListener(this);
    31. persons.setOnClickListener(this);
    32. listString.setOnClickListener( listMap.setOnClickListener(voidonClick(Viewv){
    33. switch(v.getId()){
    34. caseR.id.person:
    35. Stringurl_path="http://192.168.0.102:8080/fastjson_Project/servlet/FastJsonAction?action_flag=person";
    36. StringjsonString=HttpUtils.getJsonContent(url_path,"utf-8");
    37. Personperson=FastJsonTools.getPerson(jsonString,Person.class);
    38. //用fastJson技术解析json字符串，转换为Person对象
    39. //Personperson=JSON.parSEObject(jsonString,Person.class);
    40. Intentintent=newIntent(MainActivity.this,OtherActivity. intent.putExtra("click_flag","person");
    41. intent.putExtra("person",(Serializable)person);
    42. startActivity(intent);
    43. //Log.i(TAG,person.toString());
    44. break;
    45. caseR.id.persons:
    46. Stringurl_path2="http://192.168.0.102:8080/fastjson_Project/servlet/FastJsonAction?action_flag=persons";
    47. StringjsonString2=HttpUtils.getJsonContent(url_path2,0); background-color:inherit">//用fastjson将json字符串转换成List<Person>
    48. //List<Person>listPerson=JSON.parseArray(jsonString2,248)"> List<Person>listPerson=FastJsonTools.getPersons(jsonString2,153); font-weight:bold; background-color:inherit">class);
    49. Intentintent2= intent2.putExtra("click_flag","persons");
    50. intent2.putExtra("persons",(Serializable)listPerson);//用Intent传递List<Person>数据类型
    51. startActivity(intent2);
    52. break;
    53. caseR.id.listString:
    54. Stringurl_path3="http://192.168.0.102:8080/fastjson_Project/servlet/FastJsonAction?action_flag=listString";
    55. StringjsonString3=HttpUtils.getJsonContent(url_path3,"utf-8");
    56. //用fastjson将json字符串转换成List<String>
    57. //List<String>listString=JSON.parseArray(jsonString3,String.class);
    58. List<String>listString=FastJsonTools.getPersons(jsonString3,String. Intentintent3= intent3.putExtra("click_flag","listString");
    59. intent3.putExtra("listString",(Serializable)listString);//用Intent传递List<Person>数据类型
    60. startActivity(intent3);
    61. caseR.id.listMap:
    62. Stringurl_path4="http://192.168.0.102:8080/fastjson_Project/servlet/FastJsonAction?action_flag=listMap";
    63. StringjsonString4=HttpUtils.getJsonContent(url_path4,0); background-color:inherit">//用fastjson将json字符串转换成List<Map<String,Object>>
    64. //List<Map<String,Object>>listMap=JSON.parSEObject(jsonString4,newTypeReference<List<Map<String,Object>>>(){});
    65. List<Map<String,Object>>listMap=FastJsonTools.getListMap(jsonString4);
    66. Intentintent4= intent4.putExtra("click_flag","listMap");
    67. intent4.putExtra("listMap",(Serializable)listMap);//用Intent传递List<Map<Sting,Object>>数据类型
    68. intent4.putExtra("jsonString",jsonString4);
    69. startActivity(intent4);
    70. @SuppressLint("NewApi")
    71. voidcloseStrictMode(){
    72. StrictMode.setThreadPolicy(newStrictMode.ThreadPolicy.Builder()
    73. .detectAll().penaltyLog().build());
    74. staticStringchangeInputStream(InputStreaminputStream,Stringencode)throwsIOException{
    75. StringjsonString=null;
    76. ByteArrayOutputStreamoutputStream=newByteArrayOutputStream();
    77. byte[]data=newbyte[1024];
    78. intlen=0;
    79. while((len=inputStream.read(data))!=-1){
    80. outputStream.write(data,0,len);
    81. jsonString=newString(outputStream.toByteArray(),encode);
    82. inputStream.close();
    83. 2.OtherActivity.java
      
      copy
      1. importjava.util.Map;
      2. importandroid.R.integer;
      3. importandroid.os.Bundle;
      4. importandroid.widget.TextView;
      5. classOtherActivityextendsActivity{
      6. privateTextViewtextView;
      7. super.onCreate(savedInstanceState);
      8. setContentView(R.layout.activity_other);
      9. textView=(TextView)findViewById(R.id.msg);
      10. Intentintent=getIntent();
      11. Stringclick_flag=intent.getStringExtra("click_flag");
      12. if("person".equals(click_flag)){//如果是点击person按钮
      13. //接收Intent传递的Person对象
      14. Personperson=(Person)intent.getSerializableExtra("person");
      15. textView.setText(person.toString());
      16. //textView.setText("test:"+intent.getStringExtra("test"));
      17. if("persons".equals(click_flag)){//如果是点击persons按钮
      18. //接收Intent传递的List<Person>参数
      19. @SuppressWarnings("unchecked")
      20. List<Person>list=(List<Person>)intent
      21. .getSerializableExtra("persons");
      22. Stringpersons="";
      23. for(Personperson:list){
      24. persons+=person.toString()+"n";
      25. textView.setText(persons);
      26. if("listString".equals(click_flag)){
      27. List<String>list=(List<String>)intent
      28. .getStringArrayListExtra("listString");
      29. StringlistString="";
      30. for(Strings:list){
      31. listString+=s+"n";
      32. textView.setText(listString);
      33. if("listMap".equals(click_flag)){
      34. //接收Intent传递的List<Map<String,Object>>参数
      35. .getSerializableExtra("listMap");
      36. StringlistMapString="";
      37. for(Map<String,Object>map:list){
      38. //遍历一个Map
      39. for(Map.Entry<String,Object>entry:map.entrySet()){
      40. Stringkey=entry.getKey();
      41. Objectvalue=entry.getValue();
      42. listMapString+=""+key+":"+value+"";
      43. listMapString+="n";
      44. textView.setText(listMapString+intent.getStringExtra("jsonString"));
      45. 3.FastJsonTools.java
        
        copy
        
        importcom.alibaba.fastjson.JSON;
        importcom.alibaba.fastjson.TypeReference;
        
        *用fastjson将json字符串解析为一个JavaBean
        
        *@paramjsonString
        
        *@paramcls
        
        *@return
        
        static<T>TgetPerson(StringjsonString,Class<T>cls){
        
        Tt=null;
        
        t=JSON.parSEObject(jsonString,cls);
        
        e.printStackTrace();
        
        returnt;
        
        *用fastjson将json字符串解析成为一个List<JavaBean>及List<String>
        
        static<T>List<T>getPersons(StringjsonString,248)"> List<T>list=newArrayList<T>();
        
        list=JSON.parseArray(jsonString,0); background-color:inherit">*用fastjson将jsonString解析成List<Map<String,Object>>
        
        *@paramjsonString
        
        staticList<Map<String,Object>>getListMap(StringjsonString){
        
        //两种写法
        
        //list=JSON.parSEObject(jsonString,new
        
        //TypeReference<List<Map<String,Object>>>(){}.getType());
        
        list=JSON.parSEObject(jsonString,
        
        newTypeReference<List<Map<String,Object>>>(){
        
        });
        
        }
        
        copy
        
        packagecom.gson.data;
        importjava.io.Serializable;
        
        classPersonimplementsSerializable{
        
        5.HttpUtils.java
        
        copy
        
        packagecom.gson.http;
        importjava.net.HttpURLConnection;
        
        importjava.net.URL;
        
        /**接收path服务器端返回的InputStream,转换为json字符串
        
        *@authorben
        
        classHttpUtils{
        
        staticStringgetJsonContent(Stringurl_path,Stringencode){
        
        StringjsonString="";
        
        try{
        
        URLurl=newURL(url_path);
        
        HttpURLConnectionconnection=(HttpURLConnection)url.openConnection();
        
        connection.setConnectTimeout(3000);
        
        connection.setRequestMethod("GET");
        
        connection.setDoInput(true);//从服务器获得数据
        
        intresponseCode=connection.getResponseCode();
        
        if(200==responseCode){
        
        jsonString=changeInputStream(connection.getInputStream(),encode);
        
        //
        
        returnjsonString;
        
        6.activity_matin.xml
        
        [html] copy
        
        <LinearLayoutxmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:tools="http://schemas.android.com/tools"
        
        android:layout_width="match_parent"
        
        android:layout_height="match_parent"
        
        android:orientation="vertical">
        
        Button
        
        android:id="@+id/person"
        
        android:layout_width="match_parent"
        
        android:layout_height="wrap_content"
        
        android:text="解析Person数据"/>
        
        Button
        
        android:id="@+id/persons"
        
        android:layout_height="wrap_content"
        
        android:text="解析Persons数据"/>
        
        android:id="@+id/listString"
        
        android:text="解析listString数据" android:id="@+id/listMap"
        
        android:text="解析listMap数据"</LinearLayout>
        
        7.activity_other.xml
        
        copy
        
        <?xmlversion="1.0"encoding="utf-8"?>
        LinearLayoutxmlns:android="http://schemas.android.com/apk/res/android"
        
        android:orientation="vertical"TextView
        
        android:id="@+id/msg"
        
        8.AndroidManifest.xml
        
        copy
        
        manifestxmlns:android="http://schemas.android.com/apk/res/android"
        package="com.android.mygson"
        
        android:versionCode="1"
        
        android:versionName="1.0"uses-sdk
        
        android:minSdkVersion="8"
        
        android:targetSdkVersion="19" 
        
        spanstyle="color:#ff0000;">uses-permissionandroid:name="android.permission.INTERNET"span>
        
        application
        
        android:allowBackup="true"
        
        android:icon="@drawable/ic_launcher"
        
        android:label="@string/app_name"
        
        android:theme="@style/AppTheme"activity
        
        android:name="com.android.mygson.MainActivity"
        
        android:label="@string/app_name"intent-filteractionandroid:name="android.intent.action.MAIN"categoryandroid:name="android.intent.category.LAUNCHER"activityactivityandroid:name=".OtherActivity"applicationmanifest
        -----------------------------------------------------------------------------------------------------------------
        
        注意一点：
        
        泛型方法
        
        客户端：FastJsonToos.java 泛型方法的写法。
        
        （编辑：李大同）
        
        【声明】本站内容均来自网络，其相关言论仅代表作者个人观点，不代表本站立场。若无意侵犯到您的权利，请及时与联系站长删除相关内容!