FastJson--阿里开源的速度最快的Json和对象转换工具

import java.util.ArrayList;import java.util.List;import java.util.HashMap;import java.util.Map;import com.alibaba.fastjson.JSON;import com.alibaba.fastjson.JSONArray;import com.alibaba.fastjson.JSONObject;class User{ ???private int id; ???private String name; ???public int getId() { ???????return id; ???} ???public void setId(int id) { ???????this.id = id; ???} ???public String getName() { ???????return name; ???} ???public void setName(String name) { ???????this.name = name; ???}}class Group{ ???private int id; ???private String name; ???private List<User> list = new ArrayList<User>(); ???public int getId() { ???????return id; ???} ???public void setId(int id) { ???????this.id = id; ???} ???public String getName() { ???????return name; ???} ???public void setName(String name) { ???????this.name = name; ???} ???public List<User> getList() { ???????return list; ???} ???public void setList(List<User> list) { ???????this.list = list; ???}}class Weibo { ???private String id; ???private String city; ???public Weibo(String id, String city) { ???????this.id = id; ???????this.city = city; ???} ???public Weibo() { ???} ???public String getId() { ???????return id; ???} ???public void setId(String id) { ???????this.id = id; ???} ???public String getCity() { ???????return city; ???} ???public void setCity(String city) { ???????this.city = city; ???}}public class JsonDemo { ???public static void main(String[] args) { ???????json2JsonObjectM1();//将Json文本数据信息转换为JsonObject对象，然后利用键值对的方式获取信息 ???????json2BeanM2(); ?????//将Json文本数据转换为JavaBean数据！ ???????json2JSONArrayM3(); //将json数据转化为JSONArray: ???????json2JavaBeanM4(); ?//将JSON文本转换为JavaBean的集合；转换为单纯的1个Object：parseObject(String text, Class<T> clazz); ???????bean2JsonM5(); ?????//将JavaBean转换为Json格式的数据/Json文本 用户数据的传递：例如上传服务器 ???????bean2JSONObjectM6();//将JavaBean转换为JSON对象 ???????complexExampleM7(); //一个相对复杂的例子： ???????complex2JsonM8(); ??//一个复杂的Object到Json的Demo ???????complexMap2JsonM9();//将Map数据转换为JsonString的Demo；这个对RedBoy服务端不就直接破了嘛！ ???} ???/** ????* 将Json文本数据信息转换为JsonObject对象，然后利用键值对的方式获取信息 ????*/ ???private static void json2JsonObjectM1() { ???????//一个JsonObject文本数据 ???????String s = "{\"name\":\"liuzhao\"}"; ???????//将JsonObject数据转换为Json ???????JSONObject object = JSON.parseObject(s); ???????//利用键值对的方式获取到值 ???????System.out.println(object.get("name")); ???????/** ????????* 打印： ????????* liuzhao ????????*/ ???} ???/** ????* 将Json文本数据转换为JavaBean数据！ ????* 需要注意的是：这时候的Json文本信息中的键的名称必须和JavaBean中的字段名称一样！键中没有的在这个JavaBean中就显示为null！ ????*/ ???private static void json2BeanM2() { ???????String s = "{\"id\":\"0375\",\"city\":\"平顶山\"}"; ???????//一个简单方便 的方法将Json文本信息转换为JsonObject对象的同时转换为JavaBean对象！ ???????Weibo weibo = JSON.parseObject(s, Weibo.class);//Weibo类在下边定义 ???????System.out.println(weibo.getId()); ???????System.out.println(weibo.getCity()); ???????//打印的结果 ????0375 ???????// ????????????平顶山 ???} ???/** ????* 将Map类型的数据转换为JsonString ????*/ ???private static void complexMap2JsonM9() { ???????Group group = new Group(); ???????group.setId(1); ???????group.setName("group"); ???????User user1 = new User(); ???????user1.setId(2); ???????user1.setName("user1"); ???????User user2 = new User(); ???????user2.setId(3); ???????user2.setName("user2"); ???????group.getList().add(user1); ???????group.getList().add(user2); ???????Map<Integer, Object> map = new HashMap<Integer,Object>(); ???????map.put(1, "No.1"); ???????map.put(2, "No.2"); ???????map.put(3, group.getList()); ???????String jsonString = JSON.toJSONString(map); ???????System.out.println(jsonString); ???????/** ????????* ?输出：{1:"No.1",2:"No.2",3:[{"id":2,"name":"user1"},{"id":3,"name":"user2"}]} ????????*/ ???} ???/** ????* 由一个复杂的Object到Json的Demo ????*/ ???private static void complex2JsonM8() { ???????Group group = new Group(); ???????group.setId(1); ???????group.setName("group"); ???????User user1 = new User(); ???????user1.setId(2); ???????user1.setName("user1"); ???????User user2 = new User(); ???????user2.setId(3); ???????user2.setName("user2"); ???????group.getList().add(user1); ???????group.getList().add(user2); ???????String jsonString = JSON.toJSONString(group); ???????System.out.println(jsonString); ???????/** ????????* ?输出：{"id":1,"list":[{"id":2,"name":"user1"},{"id":3,"name":"user2"}],"name":"group"} ????????*/ ???} ???/** ????* 一个相对复杂的例子： ????* JSON文本数据： ????* ?????首先是JSONObject，转换为JSONArray； ????* ?????然后将JSONArray转换为JavaBean ????*/ ???private static void complexExampleM7() { ???????String s = "{js:[{id:\"110000\",\"city\":\"北#001京市\"},{id:\"110000\",\"city\":\"北#002京市\"}" ???????????????+ ",{id:\"110000\",\"city\":\"北#002京市\"},{id:\"110000\",\"city\":\"北#002京市\"}," ???????????????+ "{id:\"110000\",\"city\":\"#006北#005京市\"}," ???????????????+ "{id:\"110000\",\"city\":\"北#002京市\"}," ???????????????+ "{id:\"110000\",\"city\":\"北#002京市\"},{id:\"120000\",\"city\":\"天#009津市\"}]}"; ???????JSONObject object = JSON.parseObject(s); ???????Object jsonArray = object.get("js"); ???????System.out.println(jsonArray); ???????List<Weibo> list = JSON.parseArray(jsonArray+"", Weibo.class); ???????for (Weibo weibo : list) { ???????????System.out.println(weibo.getCity()); ???????} ???} ???/** ????* 将JavaBean转换为JSON对象 ????*/ ???private static void bean2JSONObjectM6() { ???????Weibo weibo = new Weibo("0373", "洛阳"); ???????JSONObject json = (JSONObject) JSON.toJSON(weibo); ???????System.out.println(json.get("id")); ???????/** ????????* 打印： ????????* 0373 ????????*/ ???} ???/** ????* 将JSON文本转换为JavaBean的集合； ????* 内部实现肯定是：首先转换为JSONArray，然后再转换为List集合 ????*/ ???private static void json2JavaBeanM4() { ???????String s = "[{\"id\":\"0375\",\"city\":\"平顶山\"},{\"id\":\"0377\",\"city\":\"南阳\"}]"; ???????List<Weibo> list = JSON.parseArray(s, Weibo.class); ???????for (Weibo weibo : list) { ???????????System.out.println(weibo.getCity()); ???????} ???????/** ????????* 打印： ????????* 平顶山 ????????* 南阳 ????????*/ ???} ???/** ????* 将json数据转化为JSONArray: ????* 注意：获取到JSONArray之后（我们这里只是获取到JSONArray而不是JavaBean的List集合） ????* 获取JSONArray中的数据转换为String类型需要在外边加""; ????*/ ???private static void json2JSONArrayM3() { ???????String s = "[{\"id\":\"0375\",\"city\":\"平顶山\"},{\"id\":\"0377\",\"city\":\"南阳\"}]"; ???????//将JSON文本转换为JSONArray ???????JSONArray array = JSON.parseArray(s); ???????//这行必须写：必须加上+"";不然会报出类型强转异常！ ???????String str = array.get(1)+""; ???????System.out.println(array.get(0)); ???????JSONObject object = JSON.parseObject(str); ???????System.out.println(object.get("id")); ???????/** ????????* {"city":"平顶山","id":"0375"} ????????0377 ????????*/ ???} ???/** ????* 将JavaBean转换为Json格式的数据/Json文本 ????* 用户数据的传递：例如上传服务器 ????*/ ???private static void bean2JsonM5() { ???????Weibo weibo = new Weibo("123456", "上海"); ???????String string = JSON.toJSONString(weibo); ???????System.out.println(string); ???????/** ????????* 打印： ????????* {"city":"上海","id":"123456"} ????????*/ ???}}