一、json-lib所需的jar包：
json-lib.jar，commons-beanutils.jar,commons-collections.jar,commons-lang.jar,commons-logging.jar,ezmorph-1.0.6.jar（可直接在网上搜索下载）。
二、使用：
1、json字符串 <------> json
String jsonStr="{\"name\" : \"peter\",\"age\" : 25,\"address\" : \"广州\",\"weight\" : \"55.5\",\"handsome\" : true}";
//String------>json ???????JSONObject jsonObject=JSONObject.fromObject(jsonStr);
//json------>String
String jsonString=jsonObject.toString();
2、java实体类 <------> json
public class User { ???private String name; ???private int age; ???private String address; ???private double weight; ???private boolean handsome; ???//省略构造和get/set方法} User user=new User("peter", 20, "广州", 55.5, true);
//java实体类------>json ???JSONObject jsonObject=JSONObject.fromObject(user);
????//{"weight":55.5,"address":"广州","name":"peter","age":20,"handsome":true} ???System.out.println(jsonObject);
3、List <------> json
???????List<String> list=new ArrayList<String>(); ???????list.add("QQQQQQ"); ???????list.add("WWWWWW"); ???????list.add("EEEEEE"); ???????list.add("RRRRRR"); ???????//List------>json ???????JSONArray jsonArray=JSONArray.fromObject(list); ????????//json------>List ???????List<String> list3=(List)JSONArray.toCollection(jsonArray);4、Map <------> json
Map<String, String> map=new HashMap<String, String>(); ???????map.put("name", "peter"); ???????map.put("sex", "Man"); ???????map.put("age", "20"); ???????//Map------json ???????JSONObject jsonMap=JSONObject.fromObject(map); ???????//json------>Map ???????Map<String, String> mapJson=(Map)JSONObject.toBean(jsonMap, Map.class);5、Set <------> json
Set<String> set=new HashSet<String>(); ???????set.add("QQQQQQ"); ???????set.add("wwwwww"); ???????set.add("eeeeee"); ???????//Set------>json ???????JSONArray array=JSONArray.fromObject(set); ???????????????//json------>Set ???????Set<String> set1=new HashSet<String>(); ???????for (Object object : array) { ???????????set1.add(object.toString()); ???????} ???????????????//报错：java.lang.ClassCastException ???????Set<String> setJson=(Set<String>)JSONArray.toCollection(array,Set.class); ???????????????//直接转List ???????List<String> list=(List)JSONArray.toCollection(array);
json-lib基础
原文地址：http://www.cnblogs.com/zhukunqiang/p/7509064.html