Json-lib的简单使用

前言

JSON-lib是一个能够将java bean/map/collection/java array/xml转换成JSON并且反过来将JSON转换成java对象的类库，它至少需要依赖如下的jar包，其他的依赖包可以参考官网http://json-lib.sourceforge.net/dependencies.html。不过现在并不推荐使用这个组件，官方也已经停止更新，可以使用jackson json。

jakarta commons-lang 2.5
jakarta commons-beanutils 1.8.0
jakarta commons-collections 3.2.1
jakarta commons-logging 1.1.1
ezmorph 1.0.6

JsonConfig参考官网的api文档说明http://json-lib.sourceforge.net/apidocs/jdk15/index.html

JSON是一个接口，其实现类有JSONArray, JSONNull, JSONObject

JSONSerializer

例子

1、基本用法，其中JSON转换后的java对象是MorphDynaBean

import java.util.Date;import net.sf.ezmorph.bean.MorphDynaBean;import net.sf.json.JSONObject;import net.sf.json.JSONSerializer;public class Demo {public static void main(String[] args) {System.out.println(JSONSerializer.toJSON(new Date()));// 打印当前日期的json格式MorphDynaBean db = (MorphDynaBean) JSONSerializer.toJava(JSONObject.fromObject("{\"Hello\":\"你好\"}"));// 返回一个动态beanSystem.out.println(db.get("Hello"));}}

{"date":1,"day":3,"hours":10,"minutes":6,"month":6,"seconds":23,"time":1435716383919,"timezoneOffset":-480,"year":115}你好

JSONObject 

例子

1、将bean/map转换为JSONObject，这里设置JsonConfig的一个属性，即循环的处理策略，其他属性的用法类似

import net.sf.json.JSONObject;import net.sf.json.JsonConfig;import net.sf.json.util.CycleDetectionStrategy;public class Demo {public static class CycleObject {private String id;private String name;private CycleObject co = this;public String getId() {return id;}public void setId(String id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}public CycleObject getCo() {return co;}public void setCo(CycleObject co) {this.co = co;}}public static void main(String[] args) {CycleObject object = new CycleObject();object.setId("1");object.setName("co");JsonConfig jsonConfig = new JsonConfig();// LENIENT：循环的成员变量返回null；NOPROP：不显示循环的成员变量；STRICT：报异常jsonConfig.setCycleDetectionStrategy(CycleDetectionStrategy.LENIENT);JSONObject json = JSONObject.fromObject(object, jsonConfig);System.out.println(json);}}

{"co":null,"id":"1","name":"co"}

2、JSON转换成MorphDynaBean

import net.sf.ezmorph.bean.MorphDynaBean;import net.sf.json.JSONObject;public class Demo {public static class CycleObject {private String id;private String name;private CycleObject co = this;public String getId() {return id;}public void setId(String id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}public CycleObject getCo() {return co;}public void setCo(CycleObject co) {this.co = co;}}public static void main(String[] args) {String json = "{name=\"json\",bool:true,int:1}";JSONObject jsonObject = JSONObject.fromObject(json);MorphDynaBean bean = (MorphDynaBean) JSONObject.toBean(jsonObject);System.out.println(bean.get("name"));}}

json

3、JSON转换成普通bean

import net.sf.json.JSONObject;public class Demo {public static class Bean {private String id;private String name;public String getId() {return id;}public void setId(String id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}@Overridepublic String toString() {return "id=" + id + ";name=" + name;}}public static void main(String[] args) {String json = "{id=\"1\",name=\"json\"}";JSONObject jsonObject = JSONObject.fromObject(json);Bean bean = (Bean) JSONObject.toBean(jsonObject, Bean.class);System.out.println(bean);}}

id=1;name=json

JSONArray

例子

1、

    boolean[] boolArray = new boolean[]{true,false,true};      JSONArray jsonArray = JSONArray.fromObject( boolArray );      System.out.println( jsonArray );      // prints [true,false,true]      List list = new ArrayList();      list.add( "first" );      list.add( "second" );      JSONArray jsonArray = JSONArray.fromObject( list );      System.out.println( jsonArray );      // prints ["first","second"]      JSONArray jsonArray = JSONArray.fromObject( "['json','is','easy']" );      System.out.println( jsonArray );      // prints ["json","is","easy"]  

2、

import net.sf.json.JSONArray;import net.sf.json.JSONObject;public class Demo {public static class Bean {private String id;private String name;public String getId() {return id;}public void setId(String id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}@Overridepublic String toString() {return "id=" + id + ";name=" + name;}}public static void main(String[] args) {boolean[] boolArray = new boolean[] { true, false, true };JSONArray jsonArray = JSONArray.fromObject(boolArray);Bean bean = new Bean();bean.setId("1");bean.setName("json");JSONObject jsonObject = JSONObject.fromObject(bean);jsonObject.put("data", jsonArray);System.out.println(jsonObject);}}

{"id":"1","name":"json","data":[true,false,true]}

xml

这个自己参考官网的例子吧http://json-lib.sourceforge.net/usage.html