昨天我们只对Android接收网络数据进行了简单介绍,今天我们完成了Android数据存储网络部分的所有内容。在此我将对这非常重要的内容进行总结。
本篇日志是对Android与WEB应用服务之间进行数据交互的总结,下篇日志是一个经典而又让人十分好奇的Android多线程断点下载应用的总结。下面我们开始Android与网络数据的交互。
一、创建WEB应用服务
使用eclipse3.5创建一个动态WEB应用,使用Struts1处理用户请求。我们此应用添加一个DispatchAction,并为它添加四个方法创建用于处理Android以各种方式提交的请求。
1.创建动态WEB工程
Project name:AndroidWebServer
Target runtime:Apache Tomcat v6.0
Dynamic web module version:2.5
Configuration:Default Configuration for Apache Tomcat v6.0
2.添加DispatchAction
package com.changcheng.web.struts.actions;
import java.io.File; import java.io.FileOutputStream; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.apache.struts.action.ActionForm; import org.apache.struts.action.ActionForward; import org.apache.struts.action.ActionMapping; import org.apache.struts.actions.DispatchAction; import com.changcheng.web.struts.forms.DataForm;
public class AndroidWebServer extends DispatchAction {
// Andoird以Get方式发送的请求 public ActionForward sendDataByGet(ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletResponse response) throws Exception { String name = request.getParameter("name"); request.setAttribute("message", "Hello " + name); return mapping.findForward("success"); }
// Andoird以Post方式发送的请求 public ActionForward sendDataByPost(ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletResponse response) throws Exception { String name = request.getParameter("name"); request.setAttribute("message", "Hello " + name); return mapping.findForward("success"); }
// Andoird以表单方式发送的请求 public ActionForward sendDataByForm(ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletResponse response) throws Exception { DataForm formbean = (DataForm) form; System.out.println("StrData:" + formbean.getStrData()); // 获取上传的文件 if (formbean.getFileData() != null && formbean.getFileData().getFileSize() > 0) { // 设置保存目录 File dir = new File(request.getSession().getServletContext() .getRealPath("/images")); if (!dir.exists()) dir.mkdirs(); // 保存文件 FileOutputStream outStream = new FileOutputStream(new File(dir, formbean.getFileData().getFileName())); outStream.write(formbean.getFileData().getFileData());// 保存文件 outStream.close(); } return null; } } |
3.向web.xml添加Struts1的ActionServlet
<servlet> <servlet-name>struts</servlet-name> <servlet-class>org.apache.struts.action.ActionServlet</servlet-class> <init-param> <param-name>config</param-name> <param-value>/WEB-INF/struts-config.xml</param-value> </init-param> </servlet> <servlet-mapping> <servlet-name>struts</servlet-name> <url-pattern>*.do</url-pattern> </servlet-mapping> |
4.struts-config.xml
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE struts-config PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 1.3//EN" "http://struts.apache.org/dtds/struts-config_1_3.dtd">
<struts-config> <form-beans> <form-bean name="dataForm" type="com.changcheng.web.struts.forms.DataForm" /> </form-beans> <action-mappings> <action path="/server" type="com.changcheng.web.struts.actions.AndroidWebServer" name="dataForm" scope="request" parameter="method"> <forward name="success" path="/WEB-INF/pages/success.jsp"/> </action> </action-mappings> </struts-config> |
二、创建Android应用
1.创建Android工程
Project name:AndroidWebClient
BuildTarget:Android2.1
Application name:AndroidWEB应用客户端
Package name:com.changcheng.web.client
Create Activity:AndroidWebClient
Min SDK Version:7
2.AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.changcheng.web.client" android:versionCode="1" android:versionName="1.0"> <application android:icon="@drawable/icon" android:label="@string/app_name"> <!-- 单元测试 --> <uses-library android:name="android.test.runner" /> <activity android:name=".AndroidWebClient" android:label="@string/app_name"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity>
</application> <uses-sdk android:minSdkVersion="7" /> <!-- 访问internet权限 --> <uses-permission android:name="android.permission.INTERNET" /> <!-- 在SDCard中创建与删除文件权限 --> <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" /> <!-- 往SDCard写入数据权限 --> <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /> <!-- 单元测试 --> <instrumentation android:name="android.test.InstrumentationTestRunner" android:targetPackage="com.changcheng.web.client" android:label="Tests for My App" /> </manifest> |
Android应用要访问Internet需要添加权限。
3.ClientService类
package com.changcheng.web.client.service;
import java.io.ByteArrayOutputStream; import java.io.DataOutputStream; import java.io.File; import java.io.FileInputStream; import java.io.InputStream; import java.net.HttpURLConnection; import java.net.URL; import java.util.HashMap; import java.util.Map; import android.os.Environment; import android.util.Log;
public class ClientService {
private static final String TAG = "ClientService";
// 以get方式发送请求 public static void sendDataToServerByGet() throws Exception { // 主机地址不可以设置为localhost或127.0.0.1,必须是本机或其他机器所在Internet网或局域网地址。 String path = "http://192.168.0.2:8080/AndroidWebServer/server.do?" + "method=sendDataByGet&name=changcheng"; URL url = new URL(path); HttpURLConnection conn = (HttpURLConnection) url.openConnection(); conn.setConnectTimeout(6 * 1000); // 请求成功 if (conn.getResponseCode() == 200) { // 获取服务器返回的数据 byte[] data = readStream(conn.getInputStream()); Log.i(TAG, new String(data, "UTF-8")); } }
// 以Post方式发送请求,面向HTTP协议编程 public static void sendDataTOserverByPost() throws Exception { String path = "http://192.168.0.2:8080/AndroidWebServer/server.do"; String params = "method=sendDataByPost&name=tingting";// 请求参数 byte[] data = params.getBytes(); URL url = new URL(path); HttpURLConnection conn = (HttpURLConnection) url.openConnection(); conn.setConnectTimeout(6 * 1000); conn.setDoOutput(true);// 发送POST请求必须设置允许输出 conn.setUseCaches(false);// 不使用Cache conn.setRequestMethod("POST"); conn.setRequestProperty("Connection", "Keep-Alive");// 维持长连接 conn.setRequestProperty("Charset", "UTF-8"); conn.setRequestProperty("Content-Length", String.valueOf(data.length)); conn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded"); DataOutputStream outStream = new DataOutputStream(conn .getOutputStream()); outStream.write(data);// 以内容实体方式发送请求参数 outStream.flush(); outStream.close(); // 请求成功 if (conn.getResponseCode() == 200) { // 获取服务器返回的数据 byte[] html = readStream(conn.getInputStream()); Log.i(TAG, new String(html, "UTF-8")); } }
// 以表单方式发送请求 public static void sendDataToServerByForm() throws Exception { Map<String, String> params = new HashMap<String, String>(); params.put("method", "sendDataByForm"); params.put("strData", "字符串数据"); // 获取SDCard中的good.jpg File file = new File(Environment.getExternalStorageDirectory(), "app_Goog_Android_w.png"); FormFile fileData = new FormFile("app_Goog_Android_w.png", new FileInputStream(file), "fileData", "application/octet-stream"); HttpRequester.post( "http://192.168.0.2:8080/AndroidWebServer/server.do", params, fileData); }
// 获取输入流数据 private static byte[] readStream(InputStream inStream) throws Exception { byte[] buffer = new byte[1024]; int len = -1; ByteArrayOutputStream outStream = new ByteArrayOutputStream(); while ((len = inStream.read(buffer)) != -1) { outStream.write(buffer, 0, len); } byte[] data = outStream.toByteArray(); outStream.close(); inStream.close(); return data; } } |
其中使用到的FormFile类:
package com.changcheng.web.client.service;
import java.io.InputStream;
/** * 上传文件 */ public class FormFile { /* 上传文件的数据 */ private byte[] data; private InputStream inStream; /* 文件名称 */ private String filname; /* 表单字段名称*/ private String formname; /* 内容类型 */ private String contentType = "application/octet-stream";
public FormFile(String filname, byte[] data, String formname, String contentType) { this.data = data; this.filname = filname; this.formname = formname; if(contentType!=null) this.contentType = contentType; }
public FormFile(String filname, InputStream inStream, String formname, String contentType) { this.filname = filname; this.formname = formname; this.inStream = inStream; if(contentType!=null) this.contentType = contentType; }
public InputStream getInStream() { return inStream; }
public void setInStream(InputStream inStream) { this.inStream = inStream; }
public byte[] getData() { return data; }
public void setData(byte[] data) { this.data = data; }
public String getFilname() { return filname; }
public void setFilname(String filname) { this.filname = filname; }
public String getFormname() { return formname; }
public void setFormname(String formname) { this.formname = formname; }
public String getContentType() { return contentType; }
public void setContentType(String contentType) { this.contentType = contentType; }
} |
其中使用到的HttpRequester类:
package com.changcheng.web.client.service;
import java.io.DataOutputStream; import java.io.InputStream; import java.net.HttpURLConnection; import java.net.URL; import java.util.ArrayList; import java.util.List; import java.util.Map; import org.apache.http.HttpResponse; import org.apache.http.NameValuePair; import org.apache.http.client.entity.UrlEncodedFormEntity; import org.apache.http.client.methods.HttpPost; import org.apache.http.impl.client.DefaultHttpClient; import org.apache.http.message.BasicNameValuePair; import org.apache.http.protocol.HTTP; import org.apache.http.util.EntityUtils; import android.util.Log;
/** * http请求发送器 */ public class HttpRequester { /** * 直接通过HTTP协议提交数据到服务器,实现如下面表单提交功能: * <FORM METHOD=POST ACTION="http://192.168.0.200:8080/ssi/fileload/test.do" enctype="multipart/form-data"> <INPUT TYPE="text" NAME="name"> <INPUT TYPE="text" NAME="id"> <input type="file" name="imagefile"/> <input type="file" name="zip"/> </FORM> * @param actionUrl 上传路径(注:避免使用localhost或127.0.0.1这样的路径测试,因为它会指向手机模拟器,你可以使用http://www.itcast.cn或http://192.168.1.10:8080这样的路径测试) * @param params 请求参数 key为参数名,value为参数值 * @param file 上传文件 */ public static String post(String actionUrl, Map<String, String> params, FormFile[] files) { try { String BOUNDARY = "---------7d 4a6d158c9"; //数据分隔线 String MULTIPART_FORM_DATA = "multipart/form-data";
URL url = new URL(actionUrl); HttpURLConnection conn = (HttpURLConnection) url.openConnection(); conn.setConnectTimeout(6* 1000); conn.setDoInput(true);//允许输入 conn.setDoOutput(true);//允许输出 conn.setUseCaches(false);//不使用Cache conn.setRequestMethod("POST"); conn.setRequestProperty("Connection", "Keep-Alive"); conn.setRequestProperty("Charset", "UTF-8"); conn.setRequestProperty("Content-Type", MULTIPART_FORM_DATA + "; boundary=" + BOUNDARY);
StringBuilder sb = new StringBuilder(); for (Map.Entry<String, String> entry : params.entrySet()) {//构建表单字段内容 sb.append("--"); sb.append(BOUNDARY); sb.append("\r\n"); sb.append("Content-Disposition: form-data; name=\""+ entry.getKey() + "\"\r\n\r\n"); sb.append(entry.getValue()); sb.append("\r\n"); } DataOutputStream outStream = new DataOutputStream(conn.getOutputStream()); outStream.write(sb.toString().getBytes());//发送表单字段数据 for(FormFile file : files){//发送文件数据 StringBuilder split = new StringBuilder(); split.append("--"); split.append(BOUNDARY); split.append("\r\n"); split.append("Content-Disposition: form-data;name=\""+ file.getFormname()+"\";filename=\""+ file.getFilname() + "\"\r\n"); split.append("Content-Type: "+ file.getContentType()+"\r\n\r\n"); outStream.write(split.toString().getBytes()); if(file.getInStream()!=null){ byte[] buffer = new byte[1024]; int len = 0; while((len = file.getInStream().read(buffer))!=-1){ outStream.write(buffer, 0, len); } file.getInStream().close(); }else{ outStream.write(file.getData(), 0, file.getData().length); } outStream.write("\r\n".getBytes()); } byte[] end_data = ("--" + BOUNDARY + "--\r\n").getBytes();//数据结束标志 outStream.write(end_data); outStream.flush(); int cah = conn.getResponseCode(); if (cah != 200) throw new RuntimeException("请求url失败"); InputStream is = conn.getInputStream(); int ch; StringBuilder b = new StringBuilder(); while( (ch = is.read()) != -1 ){ b.append((char)ch); } Log.i("ItcastHttpPost", b.toString()); outStream.close(); conn.disconnect(); return b.toString(); } catch (Exception e) { throw new RuntimeException(e); } }
/** * 提交数据到服务器 * @param actionUrl 上传路径(注:避免使用localhost或127.0.0.1这样的路径测试,因为它会指向手机模拟器,你可以使用http://www.itcast.cn或http://192.168.1.10:8080这样的路径测试) * @param params 请求参数 key为参数名,value为参数值 * @param file 上传文件 */ public static String post(String actionUrl, Map<String, String> params, FormFile file) { return post(actionUrl, params, new FormFile[]{file}); }
/** * 提交数据到服务器 * @param actionUrl 上传路径(注:避免使用localhost或127.0.0.1这样的路径测试,因为它会指向手机模拟器,你可以使用http://www.itcast.cn或http://192.168.1.10:8080这样的路径测试) * @param params 请求参数 key为参数名,value为参数值 */ public static String post(String actionUrl, Map<String, String> params) { HttpPost httpPost = new HttpPost(actionUrl); List<NameValuePair> list = new ArrayList<NameValuePair>(); for (Map.Entry<String, String> entry : params.entrySet()) {//构建表单字段内容 list.add(new BasicNameValuePair(entry.getKey(), entry.getValue())); } try { httpPost.setEntity(new UrlEncodedFormEntity(list, HTTP.UTF_8)); HttpResponse httpResponse = new DefaultHttpClient().execute(httpPost); if(httpResponse.getStatusLine().getStatusCode() == 200){ return EntityUtils.toString(httpResponse.getEntity()); } } catch (Exception e) { throw new RuntimeException(e); } return null; } } |
我们最好对HTTP协议有深入的了解,这样在编写简单数据交互应用时直接面向HTTP协议编程可以提高运行速度并减少资源的占用。
我们在最后一个方法中使用到的HttpPost类,是Apache开源组织提供的httpcomponents-client-4.0.1包。httpcomponents-client-4.0.1可以实现浏览器的大部分功能,但如果我们能不使用它就尽量不使用它,因为这会造成对手机硬件资源的占用,从而减慢应用程序的运行速度。
4.测试类
package com.changcheng.web.client.test;
import com.changcheng.web.client.service.ClientService; import android.test.AndroidTestCase;
public class TestAndroidClientService extends AndroidTestCase {
public void testSendDataToServerByGet() throws Throwable { ClientService.sendDataToServerByGet(); }
public void testSendDataToServerByPost() throws Throwable { ClientService.sendDataTOserverByPost(); }
public void testSendDataToServerByForm() throws Throwable { ClientService.sendDataToServerByForm(); } } |
5.运行
首先启动AndroidWebService应用程序,然后运行测试方法,查看运行结果。
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