工程
json包为 
代码
package com.my.json;
public class ChildBean {
private String childName;
private String childSex;
private int childAge;
public ChildBean()
{
}
public ChildBean(String childName, String childSex, int childAge) {
this.childName = childName;
this.childSex = childSex;
this.childAge = childAge;
}
public String getChildName() {
return childName;
}
public void setChildName(String childName) {
this.childName = childName;
}
public String getChildSex() {
return childSex;
}
public void setChildSex(String childSex) {
this.childSex = childSex;
}
public int getChildAge() {
return childAge;
}
public void setChildAge(int childAge) {
this.childAge = childAge;
}
@Override
public String toString() {
return "ChildBean [childName=" + childName + ", childSex=" + childSex + ", childAge=" + childAge + "]";
}
}
package com.my.json;
import java.util.ArrayList;
import java.util.List;
public class Person {
private String name;
private List<ChildBean> list = new ArrayList<ChildBean>();
private int num;
private String sex;
private int age;
public Person() {
}
public Person(String name, int num, String sex, int age) {
super();
this.name = name;
this.num = num;
this.sex = sex;
this.age = age;
}
public int getAge() {
return age;
}
public String getName() {
return name;
}
public int getNum() {
return num;
}
public String getSex() {
return sex;
}
public void setAge(int age) {
this.age = age;
}
public void setName(String name) {
this.name = name;
}
public void setNum(int num) {
this.num = num;
}
public void setSex(String sex) {
this.sex = sex;
}
public List<ChildBean> getList() {
return list;
}
public void setList(List<ChildBean> list) {
this.list = list;
}
@Override
public String toString() {
return "Person [name=" + name + ", num=" + num + ", sex=" + sex + ", age=" + age + ",list=" + list + "]";
}
}
package com.my.json;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import net.sf.json.JSONArray;
import net.sf.json.JSONObject;
import net.sf.json.JSONSerializer;
import net.sf.json.JsonConfig;
public class JsonUtil {
/**
* 简单类型：Json转化为bean
*
* @param jsonString
* @param pojoCalss
* @return
*/
public static Object jsonString2Object(String jsonString, Class pojoCalss) {
JSONObject jsonObject = JSONObject.fromObject(jsonString);
Object pojo = JSONObject.toBean(jsonObject, pojoCalss);
return pojo;
}
/**
* 复杂类型：Json转化为bean<br>
* 用法示例：<br>
* Map<String, Class> classMap = new HashMap<String, Class>();
* classMap.put("list", ChildBean.class); //指定复杂类型属性的映射关系，可以使多个放到map中<br>
* Person person=(Person)JsonUtil.jsonString2Object(str2, Person.class,
* classMap);<br>
*
* @param jsonString
* @param pojoCalss
* @return
*/
public static Object jsonString2Object(String jsonString, Class pojoCalss, Map<String, Class> classMap) {
JSONObject jobj = JSONObject.fromObject(jsonString);
return JSONObject.toBean(jobj, pojoCalss, classMap);
}
/**
* 简单|复杂类型：将java对象转换成json字符串<br>
* 支持复杂类型：Java bean 中既有属性又有list
*
* @param javaObj
* @return
*/
public static String object2JsonString(Object javaObj) {
JSONObject json = JSONObject.fromObject(javaObj);
return json.toString();
}
/**
* 从json对象集合表达式中得到一个java对象列表
*
* @param jsonString
* @param pojoClass
* @return
*/
public static List jsonList2JavaList(String jsonString, Class pojoClass) {
JSONArray jsonArray = JSONArray.fromObject(jsonString);
JSONObject jsonObject;
Object pojoValue;
List list = new ArrayList();
for (int i = 0; i < jsonArray.size(); i++) {
jsonObject = jsonArray.getJSONObject(i);
pojoValue = JSONObject.toBean(jsonObject, pojoClass);
list.add(pojoValue);
}
return list;
}
/**
* 从java对象集合表达式中得到一个json列表
*
* @param list
* @return
*/
public static String javaList2JsonList(List list) {
JSONArray jsonArray = JSONArray.fromObject(list);
return jsonArray.toString();
}
/**
* 数组转换为JSON
*
* @param array
* @return
*/
public static String javaArray2Json(Object[] array) {
JSONArray jsonarray = JSONArray.fromObject(array);
return jsonarray.toString();
}
/**
* Json数组转化为Java数组
*
* @param jsonArray
* @param clas
* @return
*/
public static Object jsonArray2JavaArrray(String jsonArray, Class clas) {
JsonConfig jconfig = new JsonConfig();
jconfig.setArrayMode(JsonConfig.MODE_OBJECT_ARRAY);
jconfig.setRootClass(clas);
JSONArray jarr = JSONArray.fromObject(jsonArray);
return JSONSerializer.toJava(jarr, jconfig);
}
/**
* Map转换成json
* @param map
* @return
*/
public static String javaMap2Json(Map<String, Object> map) {
return JSONObject.fromObject(map).toString();
}
/**
* json转化为map
* @param jsonString
* @param pojoCalss
* @return
*/
public static Object javaMap2Json(String jsonString, Class pojoCalss) {
return jsonString2Object(jsonString, pojoCalss);//调用方法jsonString2Object
}
}
package com.my.json;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
public class Test {
@SuppressWarnings("unchecked")
public static void main(String[] args) {
// 普通bean转化Json
System.out.println("普通bean转化Json:");
ChildBean p = new ChildBean("wwwww", "boy", 23);
String str = JsonUtil.object2JsonString(p);
System.out.println(str);
// 普通Json转化bean,如 {"childAge":23,"childName":"wwwww","childSex":"boy"}
System.out.println("普通Json转化bean:");
ChildBean c = (ChildBean) JsonUtil.jsonString2Object(str, ChildBean.class);
System.out.println(c);
// Java List转化为Json
System.out.println("Java List转化为Json:");
List<ChildBean> list = new ArrayList<ChildBean>();
for (int i = 0; i < 5; i++) {
ChildBean childBean = new ChildBean("wwwww" + i, "boy", i);
list.add(childBean);
}
String jsonList = JsonUtil.javaList2JsonList(list);
System.out.println(jsonList);
// json 列表转化为Java List
System.out.println("json 列表转化为Java List:");
List<ChildBean> l = (List<ChildBean>) JsonUtil.jsonList2JavaList(jsonList, ChildBean.class);
System.out.println(l);
// 复杂bean转化为Json
System.out.println("复杂bean转化为Json:");
List<ChildBean> list2 = new ArrayList<ChildBean>();
for (int i = 0; i < 10; i++) {
ChildBean childBean = new ChildBean("aaaaaa" + i, "boy", i);
list2.add(childBean);
}
Person me = new Person("zhang", 1, "man", 1);
me.setList(list2);
String str2 = JsonUtil.object2JsonString(me);
System.out.println("str2=" + str2);
// 复杂Json转化bean
System.out.println("复杂Json转化bean:");
Map<String, Class> classMap = new HashMap<String, Class>();
classMap.put("list", ChildBean.class); // 指定复杂类型属性的映射关系，可以使多个放到map中
Person person = (Person) JsonUtil.jsonString2Object(str2, Person.class, classMap);
System.out.println(person);
System.out.println(person.getList().get(0).getChildName());
// Java数组转换为JSON
System.out.println("java数组转换为JSON:");
// String[] array = {"asd","dfgd","asd","234"};
ChildBean[] array = new ChildBean[10];
for (int i = 0; i < 10; i++) {
ChildBean childBean = new ChildBean("aaaaaa" + i, "boy", i);
array[i] = childBean;
}
String jsonArray = JsonUtil.javaArray2Json(array);
System.out.println(jsonArray);
// Json数组转化为Java数组
System.out.println("Json数组转化为Java数组:");
ChildBean[] cb = (ChildBean[]) JsonUtil.jsonArray2JavaArrray(jsonArray, ChildBean.class);
System.out.println(Arrays.toString(cb));
//Map转换成json
System.out.println("Map转换成json:");
Map<String, Object> map = new HashMap<String, Object>();
map.put("userId", 1000);
map.put("userName", "张三");
map.put("userSex", "男");
String jsonStr = JsonUtil.javaMap2Json(map);
System.out.println(jsonStr);
//json转化为map
System.out.println("json转化为map:");
Map<String, Object> jmap = (Map<String, Object>)JsonUtil.javaMap2Json(jsonStr, Map.class);
System.out.println(jmap);
}
}
注意：
1.代转化的bean如果自定义了构造方法，必须写上默认的构造方法，否则Json转化时候，曝出init()方法找不到！
2.对于Date和Timestamp日期类型字段需要单独处理（本例不含这种类型，请参看我的博客《含有Date和Timestamp的Java和Json互相转化》）
时间： 2024-10-12 09:12:04