Spring学习记录

虽然我的方向是android应用开发,但大多android应用都会从后台获取数据,所以我在第一个项目中选择后台开发,尽量能对后台的处理机制能有大概的了解,并且能简单使用spring框架,MySql,进行后台开发。

今天, 本人写了简单的android登陆后台代码, 结果前台一直接收不到我返回的字符串,但是tomcat里显示前台返回了数据,

,后台尴尬了,真不给力啊,翻来覆去找不到bug.最后发现原来是少了一条注解@ResponseBody

@ResponseBody注释的作用是把返回值转化成某种格式,再传输到前台,所以,没返回值的方法是不能加这个注释的.

并且今天也更深刻的理解了Spring框架对解耦合的方式,简洁概括下,就是使用bean来给一些类初始化,所以随时可以改变要使用的类,并且可以将这些耦合关系放在xml代码中配置.

贴下代码备忘,初学记录

package com.qgmobile.xnote.controller;

import java.io.UnsupportedEncodingException;

import org.springframework.stereotype.Controller;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RequestMethod;

import org.springframework.web.bind.annotation.ResponseBody;

import com.google.gson.Gson;

import com.qgmobile.xnote.bean.User;

import com.qgmobile.xnote.service.UserService;

import javax.servlet.http.HttpServletRequest;

@Controller

public class UserController {

//获取spring的具体实现类的接口

public UserService userService;

public void setUserService(UserService userService){

this.userService = userService;

}

@ResponseBody

@RequestMapping(value = "/login", method = RequestMethod.POST)

public String login (HttpServletRequest request) throws UnsupportedEncodingException

{

request.setCharacterEncoding("utf8");

System.out.println("login 开始!");

System.out.println(request);

String userJson = request.getParameter("param");

System.out.println(userJson);

Gson gson = new Gson();

User user = gson.fromJson(userJson, User.class);

System.out.println("login 开始!");

return userService.login(user);

// return "success!";

}

@RequestMapping(value = "/register", method = RequestMethod.POST)

public String register(HttpServletRequest request)

{

String userJson = request.getParameter("param");

Gson gson = new Gson();

User user = gson.fromJson(userJson, User.class);

System.out.println("register 开始!");

return userService.register(user);

}

@RequestMapping(value = "/index", method = RequestMethod.GET)

public String index(HttpServletRequest request){

System.out.println("GOT method star!");

return "111";

}

}