FastJSON应用前测试

FastJSON 应用前测试

FastJSON是一个很好的java开源json工具类库，相比其他同类的json类库，它的速度的确是fast，最快！但是文档做得不好，在应用前不得不亲测一些功能。\

实际上其他的json处理工具都和它差不多，api也有几分相似。

一、JSON规范

JSON是一个标准规范，用于数据交互，规范的中文文档如下：

http://www.json.org/json-zh.html

参看规范，来对比JSON类库处理结果。

二、fastjson的一些简要说明

1、了解fastjson

Fastjson介绍

Fastjson是一个Java语言编写的JSON处理器。
1、遵循http://json.org标准，为其官方网站收录的参考实现之一。
2、功能qiang打，支持JDK的各种类型，包括基本的JavaBean、Collection、Map、Date、Enum、泛型。
3、无依赖，不需要例外额外的jar，能够直接跑在JDK上。
4、开源，使用Apache License 2.0协议开源。http://code.alibabatech.com/wiki/display/FastJSON/Home

如果获得Fastjson？
SVN:http://code.alibabatech.com/svn/fastjson/trunk/
WIKI:http://code.alibabatech.com/wiki/display/FastJSON/Home
Issue Tracking:http://code.alibabatech.com/jira/browse/FASTJSON

2、主要的使用入口

Fastjson API入口类是com.alibaba.fastjson.JSON，常用的序列化操作都可以在JSON类上的静态方法直接完成。

public static final Object parse(String text); // 把JSON文本parse为JSONObject或者JSONArray
public static final JSONObject parseObject(String text)； // 把JSON文本parse成JSONObject
public static final <T> T parseObject(String text, Class<T> clazz); // 把JSON文本parse为JavaBean
public static final JSONArray parseArray(String text); // 把JSON文本parse成JSONArray
public static final <T> List<T> parseArray(String text, Class<T> clazz); //把JSON文本parse成JavaBean集合
public static final String toJSONString(Object object); // 将JavaBean序列化为JSON文本
public static final String toJSONString(Object object, boolean prettyFormat); // 将JavaBean序列化为带格式的JSON文本
public static final Object toJSON(Object javaObject); 将JavaBean转换为JSONObject或者JSONArray。
 

3、有关类库的一些说明

SerializeWriter：相当于StringBuffer

JSONArray：相当于List<Object>

JSONObject：相当于Map<String, Object>

JSON反序列化没有真正数组，本质类型都是List<Object>

4、fastjson还有很多很高级的特性，比如支持注解、支持全类型序列化，这些都是很好的特性，功能强大，不在本次测试范围。

三、测试代码

package lavasoft.stu.json;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.serializer.SerializeConfig;
import com.alibaba.fastjson.serializer.SimpleDateFormatSerializer;

import java.util.*;

/**
* Created by IntelliJ IDEA.
*
* @author leizhimin 11-11-22 上午9:15
*/
public class Foo {
        private String vString = "vStringhehhehe";
        private char vchar = 'x';

        private byte vbyte = ;
        private short vshort = ;
        private int vint = ;
        private long vlong = 9999999L;

        private float vfloat = 12.1f;
        private double vdouble = 22.203d;

        private boolean vboolean = false;

//        private Date vdate = new Date();
        private Date dddd = new Date();
        private Date vDate = new Date();
        private Date v_Date = new Date();
        private Object vnull = null;

        private String[] avString = {"aaa", "bbb", "ccc"};
        private int[] avint = {, , , };
        private boolean[] avboolean = {true, false, true, true};

        private List<String> listString = new ArrayList<String>();
        private Map<String, String> map = new HashMap<String, String>();

        private Bar bar = new Bar();
        private Bar[] avBar = {new Bar(), new Bar()};
        private List<Bar> listBar = new ArrayList<Bar>();

        {
                listString.add("listString1");
                listString.add("listString2");
                listString.add("listString3");

                map.put("x", "s11111x");
                map.put("y", "s22222y");
                map.put("z", "s33333z");

                listBar.add(new Bar());
                listBar.add(new Bar());
                listBar.add(new Bar());
        }

        public String getvString() {
                return vString;
        }

        public void setvString(String vString) {
                this.vString = vString;
        }

        public char getVchar() {
                return vchar;
        }

        public void setVchar(char vchar) {
                this.vchar = vchar;
        }

        public byte getVbyte() {
                return vbyte;
        }

        public void setVbyte(byte vbyte) {
                this.vbyte = vbyte;
        }

        public short getVshort() {
                return vshort;
        }

        public void setVshort(short vshort) {
                this.vshort = vshort;
        }

        public int getVint() {
                return vint;
        }

        public void setVint(int vint) {
                this.vint = vint;
        }

        public long getVlong() {
                return vlong;
        }

        public void setVlong(long vlong) {
                this.vlong = vlong;
        }

        public float getVfloat() {
                return vfloat;
        }

        public void setVfloat(float vfloat) {
                this.vfloat = vfloat;
        }

        public double getVdouble() {
                return vdouble;
        }

        public void setVdouble(double vdouble) {
                this.vdouble = vdouble;
        }

        public boolean isVboolean() {
                return vboolean;
        }

        public void setVboolean(boolean vboolean) {
                this.vboolean = vboolean;
        }

        public Date getDddd() {
                return dddd;
        }

        public void setDddd(Date dddd) {
                this.dddd = dddd;
        }

        public Date getV_Date() {
                return v_Date;
        }

        public void setV_Date(Date v_Date) {
                this.v_Date = v_Date;
        }

        public Date getvDate() {
                return vDate;
        }

        public void setvDate(Date vDate) {
                this.vDate = vDate;
        }

        public Object getVnull() {
                return vnull;
        }

        public void setVnull(Object vnull) {
                this.vnull = vnull;
        }

        public String[] getAvString() {
                return avString;
        }

        public void setAvString(String[] avString) {
                this.avString = avString;
        }

        public int[] getAvint() {
                return avint;
        }

        public void setAvint(int[] avint) {
                this.avint = avint;
        }

        public boolean[] getAvboolean() {
                return avboolean;
        }

        public void setAvboolean(boolean[] avboolean) {
                this.avboolean = avboolean;
        }

        public List<String> getListString() {
                return listString;
        }

        public void setListString(List<String> listString) {
                this.listString = listString;
        }

        public Map<String, String> getMap() {
                return map;
        }

        public void setMap(Map<String, String> map) {
                this.map = map;
        }

        public Bar getBar() {
                return bar;
        }

        public void setBar(Bar bar) {
                this.bar = bar;
        }

        public Bar[] getAvBar() {
                return avBar;
        }

        public void setAvBar(Bar[] avBar) {
                this.avBar = avBar;
        }

        public List<Bar> getListBar() {
                return listBar;
        }

        public void setListBar(List<Bar> listBar) {
                this.listBar = listBar;
        }
}

package lavasoft.stu.json;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.serializer.SerializeConfig;
import com.alibaba.fastjson.serializer.SimpleDateFormatSerializer;

import java.util.Date;
import java.util.Random;

/**
* Created by IntelliJ IDEA.
*
* @author leizhimin 11-11-22 上午9:15
*/
public class Bar {
        public static SerializeConfig mapping = new SerializeConfig();
        private String barName;
        private int barAge;
        private Date barDate = new Date();
        static {
                mapping.put(Date.class, new SimpleDateFormatSerializer("yyyy-MM-dd"));
        }
        {
                Random r = new Random();
                barName = "sss_"+String.valueOf(r.nextFloat());
                barAge = r.nextInt();
        }

        public static void main(String[] args) {
                Object obj = JSON.toJSON(new Bar());
                String x1 = JSON.toJSONString(new Bar(), true);
                System.out.println(x1);
                String x2 = JSON.toJSONString(new Bar(), mapping);
                System.out.println(x2);
        }

        public String getBarName() {
                return barName;
        }

        public void setBarName(String barName) {
                this.barName = barName;
        }

        public int getBarAge() {
                return barAge;
        }

        public void setBarAge(int barAge) {
                this.barAge = barAge;
        }

        public Date getBarDate() {
                return barDate;
        }

        public void setBarDate(Date barDate) {
                this.barDate = barDate;
        }

        @Override
        public String toString() {
                return "Bar{" +
                                "barName='" + barName + '\'' +
                                ", barAge=" + barAge +
                                ", barDate=" + barDate +
                                '}';
        }
} 

package lavasoft.stu.json;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONArray;
import com.alibaba.fastjson.serializer.SerializeConfig;
import com.alibaba.fastjson.serializer.SimpleDateFormatSerializer;

import java.util.*;

/**
* Created by 2IntelliJ IDEA.
*
* @author leizhimin 11-11-22 上午9:45
*/
public class Test {
        private static SerializeConfig mapping = new SerializeConfig(); static {
                mapping.put(Date.class, new SimpleDateFormatSerializer("yyyy-MM-dd HH:mm:ss"));
        }

        public static void main(String[] args) {
                Foo f1 = new Foo();
                Date date = new Date();
                String text = JSON.toJSONString(date, mapping);
                System.out.println(text);
                System.out.println(JSON.toJSONString(f1, true));
                String x2 =JSON.toJSONString(f1, mapping);
                System.out.println(x2);
        }

        public static void json2List(){
                //List -> JSON array
                List<Bar> barList = new ArrayList<Bar>();
                barList.add(new Bar());
                barList.add(new Bar());
                barList.add(new Bar());
                String json= JSON.toJSONString(barList, true);
                System.out.println(json);
                //JSON array -> List
                List<Bar> barList1 = JSON.parseArray(json,Bar.class);
                for (Bar bar : barList1) {
                        System.out.println(bar.toString());
                }
        }

        public static void json2Map(){
                //Map -> JSON
                Map<String,Bar> map = new HashMap<String, Bar>();
                map.put("a",new Bar());
                map.put("b",new Bar());
                map.put("c",new Bar());
                String json = JSON.toJSONString(map,true);
                System.out.println(json);
                //JSON -> Map
                Map<String,Bar> map1 = (Map<String,Bar>)JSON.parse(json);
                for (String key : map1.keySet()) {
                        System.out.println(key+":"+map1.get(key));
                }
        }

        public static void array2JSON(){
                String[] arr_String    = {"a","b","c"};
                String json_arr_String = JSON.toJSONString(arr_String,true);
                System.out.println(json_arr_String);
                JSONArray jsonArray = JSON.parseArray(json_arr_String);
                for (Object o : jsonArray) {
                        System.out.println(o);
                }
                System.out.println(jsonArray);
        }
        public static void array2JSON2(){
                Bar[] arr_Bar    = {new Bar(),new Bar(),new Bar()};
                String json_arr_Bar = JSON.toJSONString(arr_Bar,true);
                System.out.println(json_arr_Bar);
                JSONArray jsonArray = JSON.parseArray(json_arr_Bar);
                for (Object o : jsonArray) {
                        System.out.println(o);
                }
                System.out.println(jsonArray);
        }

        public static void map2JSON(){
                Map map = new HashMap();
                map.put("a","aaa");
                map.put("b","bbb");
                map.put("c","ccc");
                String json=JSON.toJSONString(map);
                System.out.println(json);
                Map map1 = JSON.parseObject(json);
                for (Object o : map.entrySet()) {
                        Map.Entry<String,String> entry = (Map.Entry<String,String>)o;
                        System.out.println(entry.getKey()+"--->"+entry.getValue());
                }
        }
}

说明：

SerializeConfig：是对序列化过程中一些序列化过程的特殊配置，这里用作日期格式的定义。

有关需要带类型的全类型序列化过程，需要调用JSON.toJSONStringZ()方法。

需要美化输出时候，需要打开序列化美化开关，在方法中true那个参数。

输出结果：

"2011-11-23 23:30:33"
{
  "avBar":[{
    "barAge":,
    "barDate":,
    "barName":"sss_0.62378174"
  },{
    "barAge":,
    "barDate":,
    "barName":"sss_0.36014742"
  }],
  "avString":["aaa","bbb","ccc"],
  "avboolean":[true,false,true,true],
  "avint":[,,,],
  "bar":{
    "barAge":,
    "barDate":,
    "barName":"sss_0.46644872"
  },
  "dddd":,
  "listBar":[
    {
      "barAge":-,
      "barDate":,
      "barName":"sss_0.83562374"
    },
    {
      "barAge":,
      "barDate":,
      "barName":"sss_0.59483266"
    },
    {
      "barAge":,
      "barDate":,
      "barName":"sss_0.9961642"
    }
  ],
  "listString":[
    "listString1",
    "listString2",
    "listString3"
  ],
  "map":{"x":"s11111x","y":"s22222y","z":"s33333z"},
  "v_Date":,
  "vboolean":false,
  "vbyte":,
  "vchar":"x",
  "vdouble":22.203,
  "vfloat":12.1,
  "vint":,
  "vlong":,
  "vshort":
}
{"avBar":[{"barAge":,"barDate":"2011-11-23 23:30:33","barName":"sss_0.62378174"},{"barAge":,"barDate":"2011-11-23 23:30:33","barName":"sss_0.36014742"}],"avString":["aaa","bbb","ccc"],"avboolean":[true,false,true,true],"avint":[,,,],"bar":{"barAge":,"barDate":"2011-11-23 23:30:33","barName":"sss_0.46644872"},"dddd":"2011-11-23 23:30:33","listBar":[{"barAge":-,"barDate":"2011-11-23 23:30:33","barName":"sss_0.83562374"},{"barAge":,"barDate":"2011-11-23 23:30:33","barName":"sss_0.59483266"},{"barAge":,"barDate":"2011-11-23 23:30:33","barName":"sss_0.9961642"}],"listString":["listString1","listString2","listString3"],"map":{"x":"s11111x","y":"s22222y","z":"s33333z"},"v_Date":"2011-11-23 23:30:33","vboolean":false,"vbyte":,"vchar":"x","vdouble":22.203,"vfloat":12.1,"vint":,"vlong":,"vshort":}

Process finished with exit code  

fastjson通过各方面测试都很好，功能性能都是No.1，喜欢，它的源代码质量很高，作者也煞费苦心，将性能做到了最好，全免超越其他的json类库。

从其中的源代码中，可以学到很多东西，在阅读源码后，不得不佩服作者高超的程序设计水平，和高质量的编码。

 

感谢alibaba对此工具开源。

fastjson-1.1.10-sources.jar

 

由于fastjson缺乏良好的api文档，在阅读源码过程中，参考了网上一些文档：

http://code.alibabatech.com/wiki/display/FastJSON/Home

http://www.ibm.com/developerworks/cn/education/java/j-generics/section5.html

http://archive.cnblogs.com/a/1713531/

http://www.iflym.com/index.php/code/alibaba-fastjson-json-serializer-chapter-source-analyse-one-global-analyse.html

http://www.cnblogs.com/hoojo/archive/2011/04/21/2023805.html

http://archive.cnblogs.com/a/1713531/