java对象转JSON

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使用json-lib进行Java和JSON之间的转换

1. json-lib是一个java类库，提供将Java对象，包括beans, maps, collections, java arrays and XML等转换成JSON，或者反向转换的功能。
2. json-lib 主页： http://json-lib.sourceforge.net/
3.执行环境
需要以下类库支持
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
4.功能示例
这里通过JUnit-Case例子给出代码示例
package com.mai.json;import static org.junit.Assert.assertEquals;import java.util.ArrayList;import java.util.Date;import java.util.HashMap;import java.util.Iterator;import java.util.List;import java.util.Map;import net.sf.ezmorph.Morpher;import net.sf.ezmorph.MorpherRegistry;import net.sf.ezmorph.bean.BeanMorpher;import net.sf.json.JSONArray;import net.sf.json.JSONObject;import net.sf.json.util.JSONUtils;import org.apache.commons.beanutils.PropertyUtils;import org.junit.Test;public class JsonLibTest {    /*     *  普通类型、List、Collection等都是用JSONArray解析     *       *  Map、自定义类型是用JSONObject解析     *  可以将Map理解成一个对象，里面的key/value对可以理解成对象的属性/属性值     *  即{key1:value1,key2,value2......}     *      * 1.JSONObject是一个name:values集合，通过它的get(key)方法取得的是key后对应的value部分(字符串)     *         通过它的getJSONObject(key)可以取到一个JSONObject，--> 转换成map,     *         通过它的getJSONArray(key) 可以取到一个JSONArray ，     *      *      */        //一般数组转换成JSON    @Test    public void testArrayToJSON(){        boolean[] boolArray = new boolean[]{true,false,true};          JSONArray jsonArray = JSONArray.fromObject( boolArray );          System.out.println( jsonArray );          // prints [true,false,true]      }            //Collection对象转换成JSON    @Test    public void testListToJSON(){        List list = new ArrayList();          list.add( "first" );          list.add( "second" );          JSONArray jsonArray = JSONArray.fromObject( list );          System.out.println( jsonArray );          // prints ["first","second"]      }            //字符串json转换成json， 根据情况是用JSONArray或JSONObject    @Test    public void testJsonStrToJSON(){        JSONArray jsonArray = JSONArray.fromObject( "['json','is','easy']" );          System.out.println( jsonArray );          // prints ["json","is","easy"]      }            //Map转换成json， 是用jsonObject    @Test    public void testMapToJSON(){        Map map = new HashMap();          map.put( "name", "json" );          map.put( "bool", Boolean.TRUE );          map.put( "int", new Integer(1) );          map.put( "arr", new String[]{"a","b"} );          map.put( "func", "function(i){ return this.arr[i]; }" );                    JSONObject jsonObject = JSONObject.fromObject( map );          System.out.println( jsonObject );      }        //复合类型bean转成成json    @Test    public void testBeadToJSON(){        MyBean bean = new MyBean();        bean.setId("001");        bean.setName("银行卡");        bean.setDate(new Date());                List cardNum = new ArrayList();        cardNum.add("农行");        cardNum.add("工行");        cardNum.add("建行");        cardNum.add(new Person("test"));                bean.setCardNum(cardNum);                JSONObject jsonObject = JSONObject.fromObject(bean);        System.out.println(jsonObject);            }        //普通类型的json转换成对象    @Test    public void testJSONToObject() throws Exception{        String json = "{name=\"json\",bool:true,int:1,double:2.2,func:function(a){ return a; },array:[1,2]}";          JSONObject jsonObject = JSONObject.fromObject( json );         System.out.println(jsonObject);        Object bean = JSONObject.toBean( jsonObject );         assertEquals( jsonObject.get( "name" ), PropertyUtils.getProperty( bean, "name" ) );          assertEquals( jsonObject.get( "bool" ), PropertyUtils.getProperty( bean, "bool" ) );          assertEquals( jsonObject.get( "int" ), PropertyUtils.getProperty( bean, "int" ) );          assertEquals( jsonObject.get( "double" ), PropertyUtils.getProperty( bean, "double" ) );          assertEquals( jsonObject.get( "func" ), PropertyUtils.getProperty( bean, "func" ) );          System.out.println(PropertyUtils.getProperty(bean, "name"));        System.out.println(PropertyUtils.getProperty(bean, "bool"));        System.out.println(PropertyUtils.getProperty(bean, "int"));        System.out.println(PropertyUtils.getProperty(bean, "double"));        System.out.println(PropertyUtils.getProperty(bean, "func"));        System.out.println(PropertyUtils.getProperty(bean, "array"));                List arrayList = (List)JSONArray.toCollection(jsonObject.getJSONArray("array"));        for(Object object : arrayList){            System.out.println(object);        }            }            //将json解析成复合类型对象, 包含List    @Test    public void testJSONToBeanHavaList(){        String json = "{list:[{name:'test1'},{name:'test2'}],map:[{test1:{name:'test1'}},{test2:{name:'test2'}}]}";//        String json = "{list:[{name:'test1'},{name:'test2'}]}";        Map classMap = new HashMap();        classMap.put("list", Person.class);        MyBeanWithPerson diyBean = (MyBeanWithPerson)JSONObject.toBean(JSONObject.fromObject(json),MyBeanWithPerson.class , classMap);        System.out.println(diyBean);                List list = diyBean.getList();        for(Object o : list){            if(o instanceof Person){                Person p = (Person)o;                System.out.println(p.getName());            }        }    }            //将json解析成复合类型对象, 包含Map    @Test    public void testJSONToBeanHavaMap(){        //把Map看成一个对象        String json = "{list:[{name:'test1'},{name:'test2'}],map:{test1:{name:'test1'},test2:{name:'test2'}}}";        Map classMap = new HashMap();        classMap.put("list", Person.class);        classMap.put("map", Map.class);        //使用暗示，直接将json解析为指定自定义对象，其中List完全解析,Map没有完全解析        MyBeanWithPerson diyBean = (MyBeanWithPerson)JSONObject.toBean(JSONObject.fromObject(json),MyBeanWithPerson.class , classMap);        System.out.println(diyBean);                System.out.println("do the list release");        List<Person> list = diyBean.getList();        for(Person o : list){            Person p = (Person)o;            System.out.println(p.getName());        }                System.out.println("do the map release");                //先往注册器中注册变换器，需要用到ezmorph包中的类        MorpherRegistry morpherRegistry = JSONUtils.getMorpherRegistry();        Morpher dynaMorpher = new BeanMorpher( Person.class,  morpherRegistry);          morpherRegistry.registerMorpher( dynaMorpher );                          Map map = diyBean.getMap();        /*这里的map没进行类型暗示，故按默认的，里面存的为net.sf.ezmorph.bean.MorphDynaBean类型的对象*/        System.out.println(map);        List<Person> output = new ArrayList();          for( Iterator i = map.values().iterator(); i.hasNext(); ){              //使用注册器对指定DynaBean进行对象变换           output.add( (Person)morpherRegistry.morph( Person.class, i.next() ) );          }                  for(Person p : output){            System.out.println(p.getName());        }            }            }
5.下面提供上面例子所需的资源，包括jar包和代码
/Files/mailingfeng/json-lib/json-lib用例所需jar包和java类.rar