07-25 06:11 阅读 90

gson将JSON字符串转成Java对象

在Java中，将一个json格式的字符串转换为一个java类的对象。看到网上很多方法，觉得使用google的Gson的最好用。

下面一个servlet的httpRequset的处理举例：

package com.xiyou.webService;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.xiyou.util.FormatDateTime;

import com.google.gson.Gson;

class TransactionResponse {
   String action, loginAccount, createdInfoDetail, positionInfo;
}

public class UserAccountServlet extends HttpServlet {
   private static final long serialVersionUID = 1L;
   public UserAccountServlet() {
       super();
   }

   protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
       doPost(request, response);
   }

   protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

       UserAccountController userAccountController = new UserAccountController();
       String result = "";

       String jsonString =
               "{'action':'add','loginAccount':'137665123333','createdInfoDetail':'createdInfoDetail','positionInfo':'abeddafdafdadafafdfdasfadf'}";

       try {
           jsonString = request.getParameter("json");

           response.setContentType("text/html;charset=utf-8");
           response.setCharacterEncoding("utf-8");

           PrintWriter out = response.getWriter();

           Gson gson = new Gson();
           TransactionResponse tResponse = gson.fromJson(jsonString, TransactionResponse.class);
           result = tResponse.action;
           out.println(result);

           result = tResponse.loginAccount;
           out.println(result);

           result = tResponse.createdInfoDetail;
           out.println(result);

           result = tResponse.positionInfo;
           out.println(result);

           out.flush();
           out.close();

       } catch (Exception e) {
           response.setContentType("text/html;charset=utf-8");
           response.setCharacterEncoding("utf-8");
           PrintWriter out = response.getWriter();
           out.println("但愿朝阳常照我土，莫忘烈士鲜血满地 " + "@" + FormatDateTime.toLocalLongDateByNow());

           out.flush();
           out.close();
           e.printStackTrace();

       }

   }// json get the end of json

}