JSON-lib这个Java类包用于把bean,map和XML转换成JSON并能够把JSON转回成bean和DynaBean。

下载地址:http://json-lib.sourceforge.net/
还要需要的第3方包:
org.apache.commons(3.2以上版本)
org.apache.oro
net.sf.ezmorph(ezmorph-1.0.4.jar)
-------
nu.xom

1、List
Java代码
boolean[] boolArray = new boolean[]{true,false,true};     
           JSONArray jsonArray1 = JSONArray.fromObject( boolArray );     
           System.out.println( jsonArray1 );     
           // prints [true,false,true]    
             
           List list = new ArrayList();     
           list.add( "first" );     
           list.add( "second" );     
           JSONArray jsonArray2 = JSONArray.fromObject( list );     
           System.out.println( jsonArray2 );     
           // prints ["first","second"]    
 
           JSONArray jsonArray3 = JSONArray.fromObject( "['json','is','easy']" );     
           System.out.println( jsonArray3 );     
           // prints ["json","is","easy"]    

2、Map
Java代码
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 json = JSONObject.fromObject( map );     
         System.out.println( json );     
         //{"func":function(i){ return this.arr[i]; },"arr":["a","b"],"int":1,"name":"json","bool":true} 

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 json = JSONObject.fromObject( map );  
         System.out.println( json );  
         //{"func":function(i){ return this.arr[i]; },"arr":["a","b"],"int":1,"name":"json","bool":true}

3、BEAN
Java代码
/** 
     * Bean.java  
        private String name = "json";    
        private int pojoId = 1;    
        private char[] options = new char[]{'a','f'};    
        private String func1 = "function(i){ return this.options[i]; }";    
        private JSONFunction func2 = new JSONFunction(new String[]{"i"},"return this.options[i];"); 
    */   
JSONObject jsonObject = JSONObject.fromObject( new JsonBean() );     
System.out.println( jsonObject );     
 //{"func1":function(i){ return this.options[i]; },"pojoId":1,"name":"json","options":["a","f"],"func2":function(i){ return this.options[i]; }}   

/**
     * Bean.java
        private String name = "json";  
        private int pojoId = 1;  
        private char[] options = new char[]{'a','f'};  
        private String func1 = "function(i){ return this.options[i]; }";  
        private JSONFunction func2 = new JSONFunction(new String[]{"i"},"return this.options[i];");
    */
JSONObject jsonObject = JSONObject.fromObject( new JsonBean() );  
System.out.println( jsonObject );  
 //{"func1":function(i){ return this.options[i]; },"pojoId":1,"name":"json","options":["a","f"],"func2":function(i){ return this.options[i]; }} 

4、BEANS
Java代码
/** 
      * private int row ; 
          private int col ; 
          private String value ; 
      * 
      */ 
List list = new ArrayList();  
         JsonBean2 jb1 = new JsonBean2();  
         jb1.setCol(1);  
         jb1.setRow(1);  
         jb1.setValue("xx");  
           
         JsonBean2 jb2 = new JsonBean2();  
         jb2.setCol(2);  
         jb2.setRow(2);  
         jb2.setValue("");  
           
           
         list.add(jb1);  
         list.add(jb2);  
           
         JSONArray ja = JSONArray.fromObject(list);  
         System.out.println( ja.toString() );  
         //[{"value":"xx","row":1,"col":1},{"value":"","row":2,"col":2}] 

/**
      * private int row ;
          private int col ;
          private String value ;
      *
      */
List list = new ArrayList();
         JsonBean2 jb1 = new JsonBean2();
         jb1.setCol(1);
         jb1.setRow(1);
         jb1.setValue("xx");
        
         JsonBean2 jb2 = new JsonBean2();
         jb2.setCol(2);
         jb2.setRow(2);
         jb2.setValue("");
        
        
         list.add(jb1);
         list.add(jb2);
        
         JSONArray ja = JSONArray.fromObject(list);
         System.out.println( ja.toString() );
         //[{"value":"xx","row":1,"col":1},{"value":"","row":2,"col":2}]

5、String to bean
Java代码
String json = "{name=\"json\",bool:true,int:1,double:2.2,func:function(a){ return a; },array:[1,2]}";     
JSONObject jsonObject = JSONObject.fromString(json);     
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" ) );     
  List expected = JSONArray.toList( jsonObject.getJSONArray( "array" ) );     
  assertEquals( expected, (List) PropertyUtils.getProperty( bean, "array" ) );   

String json = "{name=\"json\",bool:true,int:1,double:2.2,func:function(a){ return a; },array:[1,2]}";  
JSONObject jsonObject = JSONObject.fromString(json);  
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" ) );  
  List expected = JSONArray.toList( jsonObject.getJSONArray( "array" ) );  
  assertEquals( expected, (List) PropertyUtils.getProperty( bean, "array" ) ); 

Java代码
String json = "{\"value\":\"xx\",\"row\":1,\"col\":1}";     
 JSONObject jsonObject = JSONObject.fromString(json);  
  JsonBean2 bean = (JsonBean2) JSONObject.toBean( jsonObject, JsonBean2.class );     
   assertEquals( jsonObject.get( "col" ),new Integer( bean.getCol())  );     
     assertEquals( jsonObject.get( "row" ), new Integer( bean.getRow() ) );     
     assertEquals( jsonObject.get( "value" ), bean.getValue() );   

 String json = "{\"value\":\"xx\",\"row\":1,\"col\":1}";  
  JSONObject jsonObject = JSONObject.fromString(json);
   JsonBean2 bean = (JsonBean2) JSONObject.toBean( jsonObject, JsonBean2.class );  
    assertEquals( jsonObject.get( "col" ),new Integer( bean.getCol())  );  
      assertEquals( jsonObject.get( "row" ), new Integer( bean.getRow() ) );  
      assertEquals( jsonObject.get( "value" ), bean.getValue() ); 

6 json to xml
1)
JSONObject json = new JSONObject( true );
String xml = XMLSerializer.write( json );

<o class="object" null="true">

2)
JSONObject json = JSONObject.fromObject("{\"name\":\"json\",\"bool\":true,\"int\":1}");
String xml = XMLSerializer.write( json );
<o class="object">
<name type="string">json</name>
<bool type="boolean">true</bool>
<int type="number">1</int>
</o>
<o class="object">
<name type="string">json</name>
<bool type="boolean">true</bool>
<int type="number">1</int>
</o>
3)
JSONArray json = JSONArray.fromObject("[1,2,3]");
String xml = XMLSerializer.write( json );
<a class="array">
<e type="number">1</e>
<e type="number">2</e>
<e type="number">3</e>
</a>

7 、xml to json
<a class="array">
<e type="function" params="i,j">
return matrix[i][j];
</e>
</a>
<a class="array">
<e type="function" params="i,j">
return matrix[i][j];
</e>
</a>

JSONArray json = (JSONArray) XMLSerializer.read( xml );
System.out.println( json );
// prints [function(i,j){ return matrix[i][j]; }]