JSON转换

package com.chargerlink.util.json;


import java.lang.reflect.Type;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;


import org.slf4j.Logger;
import org.slf4j.LoggerFactory;


import com.chargerlink.util.log.LogUtil;
import com.google.gson.Gson;
import com.google.gson.reflect.TypeToken;


import net.sf.json.JSONArray;
import net.sf.json.JSONObject;


@SuppressWarnings("unchecked")
public class JSONUtil {

public static final Logger logger = LoggerFactory.getLogger(JSONUtil.class);

/**
* 把对象转换为JSON字符
*/
public static String toJson(Object object) {
String jsonString = null;
if (object != null) {
if (object.getClass().isArray() || object instanceof List || object instanceof Collection || object instanceof Set) {
jsonString = JSONArray.fromObject(object).toString();
} else {
jsonString = JSONObject.fromObject(object).toString();
}
}
return jsonString == null ? "{}" : jsonString;
}

/**
* 从一个JSON 对象字符格式中得到一个java对象
*/
@SuppressWarnings("rawtypes")
public static Object fromJson(String jsonString, Class clazz) {
JSONObject jsonObject = null;
try {
jsonObject = JSONObject.fromObject(jsonString);
} catch (Exception e) {
LogUtil.error("转换异常", e);
}
return JSONObject.toBean(jsonObject, clazz);
}


/**
* 从一个JSON数组得到��java对象数组
*/
@SuppressWarnings("rawtypes")
public static Object[] fromJsonArray(String jsonString, Class clazz) {
JSONArray array = JSONArray.fromObject(jsonString);
Object[] obj = new Object[array.size()];
for (int i = 0; i < array.size(); i++) {
JSONObject jsonObject = array.getJSONObject(i);
obj[i] = JSONObject.toBean(jsonObject, clazz);
}
return obj;
}


/**
* 从一个JSON数组得到��java对象集合
* @param object
* @param clazz
* @return
*/
@SuppressWarnings({ "rawtypes" })
public static List fromJsonList(String jsonString, Class clazz) {
JSONArray array = JSONArray.fromObject(jsonString);
List list = new ArrayList();
for (Iterator iter = array.iterator(); iter.hasNext();) {
JSONObject jsonObject = (JSONObject) iter.next();
list.add(JSONObject.toBean(jsonObject, clazz));
}
return list;
}


/**
* 从json HASH表达式中获取��map，该map支持嵌套功能 形如：{"id" : "johncon", "name" : "小强"}
* 注意commons-collections版本，必须包含org.apache.commons.collections.map.MultiKeyMap
* 
* @param object
* @return
*/
@SuppressWarnings("rawtypes")
public static Map getMapFromJson(String jsonString) {
JSONObject jsonObject = JSONObject.fromObject(jsonString);
Map map = new HashMap();
for (Iterator iter = jsonObject.keys(); iter.hasNext();) {
String key = (String) iter.next();
map.put(key, jsonObject.get(key));
}
return map;
}

public static <T> T fromGson(String jsonString, Class<T> cls) {
T t = null;
try {
Gson gson = new Gson();
t = gson.fromJson(jsonString, cls);
} catch (Exception e) {
logger.error("json信息出错 : ", e);
}
return t;
}


public static <T> T fromGson(String jsonString, Type type) {
T t = null;
try {
Gson gson = new Gson();
t = gson.fromJson(jsonString, type);
} catch (Exception e) {
logger.error("json信息出错 : ", e);
}
return t;
}

public static <T> List<T> fromGsonList(String jsonString, Class<T> clazz) {
List<T> list = new ArrayList<T>();
try {
Gson gson = new Gson();
list = gson.fromJson(jsonString, new TypeToken<List<Class<T>>>() {
}.getType());
} catch (Exception e) {
e.printStackTrace();
}
return list;
}


public static List<Map<String, Object>> listKeyMaps(String jsonString) {
List<Map<String, Object>> list = new ArrayList<Map<String, Object>>();
try {
Gson gson = new Gson();
list = gson.fromJson(jsonString,new TypeToken<List<Map<String, Object>>>() {}.getType());
} catch (Exception e) {
e.printStackTrace();
}
return list;
}

public static Map<String, Object> getMap(String jsonString) {
Map<String, Object> map = new HashMap<String,Object>();
try {
Gson gson = new Gson();
map = gson.fromJson(jsonString,new TypeToken<Map<String, Object>>() {}.getType());
} catch (Exception e) {
e.printStackTrace();
}
return map;
}


/**
* 从json数组中得到相应java数组 json形如：["123", "456"]
*/
public static Object[] getObjectArrayFromJson(String jsonString) {
JSONArray jsonArray = JSONArray.fromObject(jsonString);
return jsonArray.toArray();
}


public static void main(String[] args) throws Exception {
/* String x = null;
List<Person> listt = new ArrayList<Person>();
for (int i = 0; i <= 100; i++) {
listt.add(new Person("张三" + i, i));
}
try {
x = getJSONString(listt);
} catch (Exception e) {
LogUtil.error("", e);
}
System.out.println(x);
listt = (List<Person>) getDTOList(x, Person.class);
System.out.println(listt.size());*/
}


public static void testJsonConfig() throws Exception {
// Person person = new Person("张三", 18);
// Dog dog = new Dog("张三", "黑背");
// Hourse hourse = new Hourse("唐宁08, person, dog);
// String str = getJSONString(hourse);
// System.out.println(str);
// Map x = new HashMap();
// x.put("person", Person.class);
// x.put("Dog", Dog.class);
// getDTO(str, Hourse.class);
}


public static class Hourse {
private String adress;
private Person person;
private Dog dog;


public Hourse() {
}


public Hourse(String adress, Person person, Dog dog) {
this.adress = adress;
this.person = person;
this.dog = dog;
}


public String getAdress() {
return adress;
}


public void setAdress(String adress) {
this.adress = adress;
}


public Person getPerson() {
return person;
}


public void setPerson(Person person) {
this.person = person;
}


public Dog getDog() {
return dog;
}


public void setDog(Dog dog) {
this.dog = dog;
}
}


public static class Person {
private String name;
private int age;


public Person() {
}


public Person(String name, int age) {
this.name = name;
this.age = age;
}


public String getName() {
return name;
}


public void setName(String name) {
this.name = name;
}


public int getAge() {
return age;
}


public void setAge(int age) {
this.age = age;
}


public String toString() {
return "name :" + name + "___age :" + age;
}
}


public static class Dog {
private String master;
private String variety;


public Dog() {
}


public Dog(String master, String variety) {
this.master = master;
this.variety = variety;
}


public String getMaster() {
return master;
}


public void setMaster(String master) {
this.master = master;
}


public String getVariety() {
return variety;
}


public void setVariety(String variety) {
this.variety = variety;
}


public String toString() {
return " master :" + master + " __variety" + variety;
}
}
}