json格式解析的全过程

package com.zml.pojo;

/**

* @author 郑明亮

* @Time：2016年2月2日 下午10:35:05

* @version 1.0

*/

public class Person {

String name;

String sex;

String QQ;

String contact;

public Person() {

// TODO Auto-generated constructor stub

}

public Person(String name, String sex, String qQ, String contact) {

super();

this.name = name;

&
1eedf
nbsp; this.sex = sex;

QQ = qQ;

this.contact = contact;

}

/**

* @return the name

*/

public String getName() {

return name;

}

/**

* @param name

* the name to set

*/

public void setName(String name) {

this.name = name;

}

/**

* @return the sex

*/

public String getSex() {

return sex;

}

/**

* @param sex

* the sex to set

*/

public void setSex(String sex) {

this.sex = sex;

}

/**

* @return the qQ

*/

public String getQQ() {

return QQ;

}

/**

* @param qQ

* the qQ to set

*/

public void setQQ(String qQ) {

QQ = qQ;

}

/**

* @return the contact

*/

public String getContact() {

return contact;

}

/**

* @param contact

* the contact to set

*/

public void setContact(String contact) {

this.contact = contact;

}

/*

* (non-Javadoc)

*

* @see java.lang.Object#toString()

*/

@Override

public String toString() {

return "Person [name=" + name + ", sex=" + sex + ", QQ=" + QQ

+ ", contact=" + contact + "]";

}

}

2.我写了一个工具类，用来生成上述的四种类型的数据；

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package com.zml.utils;

import java.util.ArrayList;

import java.util.HashMap;

import java.util.List;

import java.util.Map;

import com.zml.pojo.Person;

/**

* 用于生成四种类型的数据来测试json解析：

* ①Person对象类型 ②List<Person> ③List<String> ④List<Map<String,Object>>

*

* @author 郑明亮

* @Time：2016年2月2日 下午10:38:40

* @version 1.0

*/

public class DataUtil {

public static Person getPerson() {

return new Person("郑明亮", "男", "1072307340", "15733100573");

}

public static List<Person> getPersons() {

List<Person> list = new ArrayList<Person>();

list.add(getPerson());

list.add(new Person("张三", "男", "123456789", "98765432"));

list.add(new Person("李四", "女", "762348234", "12312124324"));

return list;

}

public static List<String> getStrings(){

List<String>list = new ArrayList<String>();

list.add("郑明亮");

list.add("张三");

list.add("李四");

return list;

}

public static List<Map<String,Object>> getMaps(){

List<Map<String,Object>> list = new ArrayList<Map<String,Object>>();

Map<String,Object> map = new HashMap<String, Object>();

map.put("name","郑明亮" );

map.put("blog", "blog.csdn.net/zml_2015");

map.put("person", getPerson());

list.add(map);

return list;

}

}

3.接下来就是写json数据类型的转换类了

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package com.zml.utils;

import net.sf.json.JSONObject;

/**

* @author 郑明亮

* @Time：2016年2月2日 上午12:18:38

* @version 1.0

*/

public class JsonTools {

public static String createJsonString(String key,Object value){

JSONObject jsonObject=new JSONObject();

jsonObject.put(key, value);

return jsonObject.toString();

}

}

4.进行测试，看是否将上述4种数据转换为了json的数据类型

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package com.zml.test;

import com.zml.utils.DataUtil;

import com.zml.utils.JsonTools;

/**

* @author 郑明亮

* @Time：2016年2月2日 上午12:27:29

* @version 1.0

*/

public class testjson {

public static void main(String[] args) {

String jsonString;

jsonString = JsonTools.createJsonString("person",DataUtil.getPerson());

System.out.println(jsonString);

jsonString = JsonTools.createJsonString("persons",DataUtil.getPersons());

System.out.println(jsonString);

jsonString = JsonTools.createJsonString("strings",DataUtil.getStrings());

System.out.println(jsonString);

jsonString = JsonTools.createJsonString("maps",DataUtil.getMaps());

System.out.println(jsonString);

}

}



5.测试成功后，建立Servlet类，以方便将json数据传输给客户端

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<p>package com.zml.test;</p><p>import java.io.IOException;

import java.io.PrintWriter;</p><p>import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;</p><p>import com.zml.utils.DataUtil;

import com.zml.utils.JsonTools;</p><p>/**

* @author 郑明亮

* @Time：2016年2月2日 下午10:54:26

* @version 1.0

*/

public class JsonServlet extends HttpServlet {</p><p> /**

* Constructor of the object.

*/

public JsonServlet() {

super();

}</p><p> /**

* Destruction of the servlet. <br>

*/

public void destroy() {

super.destroy(); // Just puts "destroy" string in log

// Put your code here

}</p><p> /**

* The doGet method of the servlet. <br>

*

* This method is called when a form has its tag value method equals to get.

*

* @param request

* the request send by the client to the server

* @param response

* the response send by the server to the client

* @throws ServletException

* if an error occurred

* @throws IOException

* if an error occurred

*/

public void doGet(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

this.doPost(request, response);</p><p> }</p><p> /**

* The doPost method of the servlet. <br>

*

* This method is called when a form has its tag value method equals to

* post.

*

* @param request

* the request send by the client to the server

* @param response

* the response send by the server to the client

* @throws ServletException

* if an error occurred

* @throws IOException

* if an error occurred

*/

public void doPost(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {</p><p> response.setContentType("text/html;charset=utf-8");

request.setCharacterEncoding("utf-8");

response.setCharacterEncoding("utf-8");

PrintWriter out = response.getWriter();</p><p> String jsonString="";

String actionString = request.getParameter("action");

if (actionString.equals("person")) {

jsonString = JsonTools.createJsonString("person",DataUtil.getPerson());</p><p> } else if (actionString.equals("persons")) {

jsonString = JsonTools.createJsonString("persons",DataUtil.getPersons());</p><p> } else if (actionString.equals("strings")) {

jsonString = JsonTools.createJsonString("strings",DataUtil.getStrings());</p><p> } else if (actionString.equals("maps")) {

jsonString = JsonTools.createJsonString("maps",DataUtil.getMaps());

}

out.write(jsonString);</p><p> }</p><p> /**

* Initialization of the servlet. <br>

*

* @throws ServletException

* if an error occurs

*/

public void init() throws ServletException {

// Put your code here

}</p><p>}

</p>

通过网址访问可得到的JSON数据：









二、客户端解析json数据

这里暂时只贴出重要的解析部分，

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package com.zml.util;

import java.util.ArrayList;

import java.util.HashMap;

import java.util.Iterator;

import java.util.List;

import java.util.Map;

import org.json.JSONArray;

import org.json.JSONException;

import org.json.JSONObject;

import com.zml.pojo.Person;

/**

* 解析数据：将json字符串解析还原成原来的数据类型

*

* @author 郑明亮

* @date 2016-2-3 上午12:11:57

* @version 1.0

*/

public class JsonTools {

public static Person getPerson(String key, String jsonString) {

Person person = new Person();

// 将json字符串转换成json对象

try {

JSONObject jsonObject = new JSONObject(jsonString);

// 将json对象根据key(person)，拿到对应的value(Person对象)值

JSONObject jsonObject2 = jsonObject.getJSONObject(key);

// 将拿到的对象set到一个person对象中

person.setName(jsonObject2.getString("name"));

person.setSex(jsonObject2.getString("sex"));

person.setQQ(jsonObject2.getString("QQ"));

person.setContact(jsonObject2.getString("contact"));

} catch (JSONException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

return person;

}

public static List<Person> getPersons(String key, String jsonString) {

List<Person> list = new ArrayList<Person>();

JSONObject jsonObject;

try {

jsonObject = new JSONObject(jsonString);

JSONArray Persons = jsonObject.getJSONArray(key);

for (int i = 0; i < Persons.length(); i++) {

Person person = new Person();

JSONObject jsonObject2 = Persons.getJSONObject(i);

person.setName(jsonObject2.getString("name"));

person.setSex(jsonObject2.getString("sex"));

person.setQQ(jsonObject2.getString("QQ"));

person.setContact(jsonObject2.getString("contact"));

list.add(person);

}

} catch (JSONException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

return list;

}

public static List<String> getStrings(String key, String jsonString) {

List<String> list = new ArrayList<String>();

try {

JSONObject jsonObject = new JSONObject(jsonString);

JSONArray StringArray = jsonObject.getJSONArray(key);

for (int i = 0; i < StringArray.length(); i++) {

String str = StringArray.getString(i);

list.add(str);

}

} catch (Exception e) {

// TODO: handle exception

}

return list;

}

public static List<Map<String, Object>> getMaps(String key,

String jsonString) {

List<Map<String, Object>> list = new ArrayList<Map<String, Object>>();

try {

JSONObject jsonObject = new JSONObject(jsonString);

JSONArray mapsArray = jsonObject.getJSONArray(key);

for (int i = 0; i < mapsArray.length(); i++) {

JSONObject jsonObject2 = mapsArray.getJSONObject(i);

Map<String, Object> map = new HashMap<String, Object>();

// 查看Map中的键值对的key值

Iterator<String> iterator = jsonObject2.keys();

while (iterator.hasNext()) {

String json_key = iterator.next();

Object json_value = jsonObject2.get(json_key);

if(json_value==null){

//当键值对中的value为空值时，将value置为空字符串；

json_value="";

}

map.put(json_key, json_value);

}

list.add(map);

}

} catch (Exception e) {

// TODO: handle exception

}

return list;

}

}

需要注意的是上述，客户端和服务器端虽然都用到了JSONObject类，但是引用的不是一个jar包中的内容哦；客户端的是引用的 org.json.JSONObject;而服务器端引用的是net.sf.json.JSONObject;