1，数组，集合转换为JSON
如果要将数组，集合转换为JSON，那么可以JSONArray.fromObject()方法来实现，同时也可以使用JSONSerializer.toJSON()来做到。
// 数组
boolean[] boolArray = new boolean[] { true, false, true };
JSONArray jsonArray = JSONArray.fromObject(boolArray);
assertEquals("[true,false,true]", jsonArray.toString());
// 集合
List<String> list = new ArrayList<String>();
list.add("first");
list.add("second");
JSONArray jsonArray = JSONArray.fromObject(list);
assertEquals("[\"first\",\"second\"]", jsonArray.toString());
JSONSerializer.toJSON()方法的例子
// 数组
boolean[] boolArray = new boolean[] { true, false, true };
JSON json = JSONSerializer.toJSON(boolArray);
assertEquals("[true,false,true]", json.toString());
// 集合
List<String> list = new ArrayList<String>();
list.add("first");
list.add("second");
JSON json = JSONSerializer.toJSON(list);
assertEquals("[\"first\",\"second\"]", json.toString());
2，Map,JAVA BEAN转换为JSON
如果要将Map,JAVA BEAN转换为JSON，那么可以JSONObject.fromObject()方法来实现，同时也可以使用JSONSerializer.toJSON()来做到。
//MAP
Map<String, Object> map = new HashMap<String, Object>();
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);
assertEquals(
"{\"arr\":[\"a\",\"b\"],\"int\":1,\"name\":\"json\",\"func\":function(i){ return this.arr[i]; },\"bool\":true}",
jsonObject.toString());
//JAVA BEAN
User user = new User();
user.setName("Jimmy Liu");
user.setAge(28);
user.setAddresses(new String[] { "shenzhen,changsha" });
User friend = new User();
friend.setName("Eric Liu");
friend.setAge(30);
friend.setAddresses(new String[] { "shenzhen,nanchange" });
List<User> friends = new ArrayList<User>();
friends.add(friend);
user.setFriends(friends);
JSONObject jsonObject = JSONObject.fromObject(user);
assertEquals(
"{\"friends\":[{\"friends\":[],\"age\":30,\"name\":\"Eric Liu\",\"addresses\":[\"shenzhen,nanchange\"],\"func1\":function(data){ alert(data); },\"func2\":function(data){ return data; }}],\"name\":\"Jimmy Liu\",\"age\":28,\"addresses\":[\"shenzhen,changsha\"],\"func1\":function(data){ alert(data); },\"func2\":function(data){ return data; }}",
jsonObject.toString());
3,JSON转换为动态BEAN,特定BEAN
如果要将JSON转换为动态BEAN,特定BEAN，那么可以JSONObject.toBean()方法来实现
//转换为动态BEAN
String json = "{name=\"json\",bool:true,int:1,double:2.2,func:function(a){ return a; },array:[1,2]}";
JSONObject jsonObject = JSONObject.fromObject(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.size(), ((List) PropertyUtils.getProperty(bean,
"array")).size());
//转换为特定BEAN
String json = "{\"friends\":[],\"name\":\"Jimmy Liu\",\"age\":28,\"addresses\":[\"shenzhen,changsha\"],\"func1\":function(data){ alert(data); },\"func2\":function(data){ return data; }}";
JSONObject jsonObject = JSONObject.fromObject(json);
User user = (User) JSONObject.toBean(jsonObject, User.class);
assertEquals(jsonObject.get("name"), user.getName());
assertEquals(jsonObject.get("age"), user.getAge());
assertEquals(jsonObject.get("func1"), user.getFunc1());
List expected = JSONArray.toList(jsonObject.getJSONArray("addresses"));
assertEquals(expected.size(), user.getAddresses().length);
// 在JSON转换为Bean时，如果bean包括集合的属性且集合包括其他JAVA BEAN,默认情况下，JSONLIB将转为动态BEAN
json = "{'roleName':'administrator','privilegeList':[{'privilegeName':'system-manager'},{'privilegeName':'supplier-manager'}]}";
Map<String, Object> classMap = new HashMap<String, Object>();
classMap.put("privilegeList", Privilege.class);
Role role = (Role) JSONObject.toBean(JSONObject.fromObject(json),
Role.class, classMap);
jsonObject = JSONObject.fromObject(json);
assertEquals(jsonObject.get("roleName"), role.getRoleName());
List privilegeList = JSONArray.toList(jsonObject
.getJSONArray("privilegeList"));
assertEquals(privilegeList.size(), role.getPrivilegeList().size());
assertEquals(PropertyUtils.getProperty(privilegeList.get(0),
"privilegeName"), role.getPrivilegeList().get(0)
.getPrivilegeName());
4,JSON TO XML
可以利用XMLSerializer.write()方法将JSON转化为XML，同时利用的Setter方法控制XML的输出，比如，你能够改变XML的根元素，你可以注册，管理namespaces ，还可以向XML增加属性。
//Boolean
JSONObject json = new JSONObject(true);
String xml = new XMLSerializer().write(json);
System.out.println(xml);
//Object
JSONObject json = JSONObject
.fromObject("{\"privilegeName\":\"system-manager\"}");
XMLSerializer xmlSerializer = new XMLSerializer();
xmlSerializer.setObjectName("privilege");
String xml = xmlSerializer.write(json);
System.out.println(xml);
//Array
JSONArray json = JSONArray.fromObject("[1,2,3]");
XMLSerializer xmlSerializer = new XMLSerializer();
xmlSerializer.setArrayName("array");
xmlSerializer.setElementName("element");
String xml = xmlSerializer.write(json);
System.out.println(xml);
5，XML To JSON
XMLSerializer.read()方法将XML转化为JSON
JSONObject json = (JSONObject) new XMLSerializer()
.read("<?xml version=\"1.0\" encoding=\"UTF-8\"?><o><privilegeName type=\"string\">system-manager</privilegeName></o>" );
System.out.println( json );
6，测试用到的JAVA BEAN,去除了Getter，Setter方法
public class User {
private String name;
private Integer age;
private String[] addresses;
private List<User> friends;
private String func1 = "function(data){ alert(data); }";
private JSONFunction func2 = new JSONFunction(new String[] { "data" },
"return data;");
}
public class Role {
private String roleName;
private List<Privilege> privilegeList;
}
public class Privilege {
private String privilegeName;
}
7，maven依赖
<dependency> <groupId>net.sf.json-lib</groupId> <artifactId>json-lib</artifactId> <version>2.4</version> <classifier>jdk15</classifier> </dependency> <dependency> <groupId>xom</groupId> <artifactId>xom</artifactId> <version>1.1</version> </dependency>