开篇
之前的一篇博客:Androidannotation使用之@Rest获取资源及用户登录验证(一):http://blog.csdn.net/nupt123456789/article/details/24384713 主要写了Rest在用户登录的时候,需要JSESSION字段的问题。本博客主要写JSON格式的转换。
@Rest的参考文档:
https://github.com/excilys/androidannotations/wiki/Rest-API#rest
简介:
从上一篇博客中,我们可以看出,我们直接再浏览器中请求http://192.168.0.101:8080/cbvr/getUserInfoList.action 的时候,返回的字符串其实是JSON格式。我们上一篇博客,就是把它直接当String进行处理了,没有出现什么问题。当然,我们接下来,可以使用GSON对String进行解析,这没有什么问题。然而,我们通常想,我们换一个转换器不就行了吗?代码如下:
/* * $filename: UserService.java,v $ * $Date: 2014-4-20 $ * Copyright (C) ZhengHaibo, Inc. All rights reserved. * This software is Made by Zhenghaibo. */ package com.example.testaa; import org.androidannotations.annotations.rest.Accept; import org.androidannotations.annotations.rest.Post; import org.androidannotations.annotations.rest.Rest; import org.androidannotations.api.rest.MediaType; import org.androidannotations.api.rest.RestClientErrorHandling; import org.springframework.http.ResponseEntity; import org.springframework.http.converter.json.GsonHttpMessageConverter; /* *@author: ZhengHaibo *web: http://blog.csdn.net/nuptboyzhb *mail: zhb931706659@126.com *2014-4-20 Nanjing,njupt,China */ @Rest(rootUrl = "http://192.168.0.101:8080/cbvr", converters = {GsonHttpMessageConverter.class}) public interface UserService extends RestClientErrorHandling{ @Post("/getUserInfoList.action") @Accept(MediaType.APPLICATION_JSON) ResponseEntity<DataGrid> getUserInfoList(); }
这样,我们就使用了Gson的消息转换器,当然,需要导入GSON相关的包。但是运行程序的时候,发现报错如下:
05-02 16:58:32.644: W/System.err(7454): org.springframework.web.client.RestClientException: Could not extract response: no suitable HttpMessageConverter found for response type [com.example.testaa.DataGrid] and content type [text/html;charset=UTF-8]
说什么没有合适的HttpMessageConverter,我以为是android端的问题,就换了好几个转换器,结果依然报错。然后,才发现,原来不是android端的问题,是服务端。服务端每次输出json字符串时,都设置了如下属性:
response.setContentType("text/html;charset=UTF-8");
原来是这个原因,于是,将服务端的修改为如下:
response.setContentType("application/json;charset=utf-8");
然后,再次运行,OK了,大功告成!这样,我们就可以直接获得到转换为JSON格式之后的对象了。为了增加程序的健壮性,为其添加了ErrorHandler处理。余下代码如下:
package com.example.testaa; /* *@author: ZhengHaibo *web: http://blog.csdn.net/nuptboyzhb *GitHub https://github.com/nuptboyzhb *mail: zhb931706659@126.com *2014-1-12 Nanjing,njupt,China */ public class Userinfo { /** * {field : ‘yhm‘,title : ‘用户名‘,width : 150}, {field : ‘pwd‘,title : ‘密码‘,width : 150}, {field : ‘yhqx‘,title : ‘用户权限‘,width : 150}, {field : ‘zcsj‘,title : ‘注册时间‘,width : 150}, {field : ‘bz‘,title : ‘备注‘,width : 180}] ]; */ private String id; private String yhm; private String pwd; private String yhqx; private String zcsj; private String bz; public String getId() { return id; } public void setId(String id) { this.id = id; } public String getYhm() { return yhm; } public void setYhm(String yhm) { this.yhm = yhm; } public String getPwd() { return pwd; } public void setPwd(String pwd) { this.pwd = pwd; } public String getYhqx() { return yhqx; } public void setYhqx(String yhqx) { this.yhqx = yhqx; } public String getZcsj() { return zcsj; } public void setZcsj(String zcsj) { this.zcsj = zcsj; } public String getBz() { return bz; } public void setBz(String bz) { this.bz = bz; } }
DataGrid类
/* * $filename: DataGrid.java,v $ * $Date: 2013-10-11 $ * Copyright (C) ZhengHaibo, Inc. All rights reserved. * This software is Made by Zhenghaibo. */ package com.example.testaa; /* *@author: ZhengHaibo *web: http://blog.csdn.net/nuptboyzhb *mail: zhb931706659@126.com *2013-10-11 Nanjing,njupt,China */ public class DataGrid{ private int total; private Userinfo[] rows; public Userinfo[] getRows() { return rows; } public void setRows(Userinfo[] rows) { this.rows = rows; } public int getTotal() { return total; } public DataGrid(int total, Userinfo[] rows) { this.total = total; this.rows = rows; } public DataGrid( ) { } public void setTotal(int total) { this.total = total; } }
ErrorHandler
/* * $filename: ErrorHandlerForUserService.java,v $ * $Date: 2014-4-29 $ * Copyright (C) ZhengHaibo, Inc. All rights reserved. * This software is Made by Zhenghaibo. */ package com.example.testaa; import org.androidannotations.annotations.EBean; import org.androidannotations.annotations.RootContext; import org.androidannotations.annotations.UiThread; import org.androidannotations.api.rest.RestErrorHandler; import org.springframework.web.client.RestClientException; import android.content.Context; import android.util.Log; import android.widget.Toast; /* *@author: ZhengHaibo *web: http://blog.csdn.net/nuptboyzhb *mail: zhb931706659@126.com *2014-4-29 Nanjing,njupt,China */ @EBean public class MyErrorHandler implements RestErrorHandler { @RootContext Context context; @Override public void onRestClientExceptionThrown(RestClientException e) { // TODO Auto-generated method stub e.printStackTrace(); Log.d("REST", e.toString()); showError(); } @UiThread void showError(){ Toast.makeText(context, "Rest Error...", Toast.LENGTH_SHORT).show(); } }
剩下的就是MainActivity
package com.example.testaa; import org.androidannotations.annotations.AfterViews; import org.androidannotations.annotations.Background; import org.androidannotations.annotations.Bean; import org.androidannotations.annotations.Click; import org.androidannotations.annotations.EActivity; import org.androidannotations.annotations.UiThread; import org.androidannotations.annotations.ViewById; import org.androidannotations.annotations.rest.RestService; import org.springframework.http.ResponseEntity; import android.app.Activity; import android.util.Log; import android.widget.Button; import android.widget.TextView; /* *@author: ZhengHaibo *web: http://blog.csdn.net/nuptboyzhb *mail: zhb931706659@126.com *2014-4-15 Nanjing,njupt,China */ @EActivity(R.layout.activity_main) public class MainActivity extends Activity { private static final String TAG="AAREST"; @ViewById Button getUser; @ViewById TextView myTextView; @RestService UserService userService; @Bean MyErrorHandler errorHandlerForUserService; @AfterViews void afterView(){ //设置ErrorHandler userService.setRestErrorHandler(errorHandlerForUserService); } /** * 获取用户列表 */ @Click void getUser() { getUserInBackground(); } /** * 获取用户列表 * 无需登录 */ @Background void getUserInBackground(){ //String result = userService.getUserInfoList(); //Gson gson = new Gson(); //DataGrid dataGrid = gson.fromJson(result, DataGrid.class); ResponseEntity<DataGrid> responseEntiy = userService.getUserInfoList(); if(null == responseEntiy){ return; } DataGrid dataGrid = responseEntiy.getBody(); Userinfo[] userinfos= dataGrid.getRows(); String string = ""; for(Userinfo userinfo:userinfos){ string = string + "user:"+ userinfo.getYhm(); Log.d(TAG, userinfo.getYhm()); } Log.d(TAG, string); displayTextView(string); } @UiThread void displayTextView(String string){ myTextView.setText(string); } }
总结:
整个项目使用AndroidAnnotation框架。本次博客主要解决服务端和android进行json交互的情况。
缺点:Response的setContentType设置修改后,可能影响原网站对浏览器的支持,因此,需要根据不同场景进行选择。
整个项目下载地址:http://download.csdn.net/detail/nuptboyzhb/7283863
未经允许,不得用于商业目的