Java JSON入门

一、所需jar包　

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

下载地址：

http://json-lib.sourceforge.net/
http://ezmorph.sourceforge.net/
http://morph.sourceforge.net/
http://www.docjar.com

二、举例(json官网 ：http://json-lib.sourceforge.net/usage.html)

　　1、from beans to json

	public class Person {
		private String username;
		private String password;
	}
	@Test
	public void demo1() {
		Person person1 = new Person("aaa", "aaa");
		Person person2 = new Person("bbb", "bbb");
		List<Person> list = new ArrayList<Person>();
		list.add(person1);
		list.add(person2);
		JSONArray.fromObject(list);
		JSONArray jsonArray = JSONArray.fromObject(list);
		System.out.println( jsonArray.toString());
	}
　　　　　//[{"password":"aaa","username":"aaa"},{"password":"bbb","username":"bbb"}]

　　from json to beans

class MyBean{
   private List data;
   // getters & setters
}
class Person{
   private String name;
   // getters & setters
}
String json = "{'data':[{'name':'Wallace'},{'name':'Grommit'}]}";
Map classMap = new HashMap();
classMap.put( "data", Person.class );
MyBean bean = JSONObject.toBean( JSONObject.fromObject(json), MyBean.class, classMap );  

　2、from bean to json

class MyBean{
   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];");  

   // getters & setters
   ...
}  

JSONObject jsonObject = JSONObject.fromObject( new MyBean() );
System.out.println( jsonObject );
/* prints
  {"name":"json","pojoId":1,"options":["a","f"],
  "func1":function(i){ return this.options[i];},
  "func2":function(i){ return this.options[i];}}
*/

　　　from json to bean

String json = "{bool:true,integer:1,string:\"json\"}";
JSONObject jsonObject = JSONObject.fromObject( json );
BeanA bean = (BeanA) JSONObject.toBean( jsonObject, BeanA.class );