这篇文章主要实现了在Android中使用JDK的HttpURLConnection和Apache的HttpClient访问网络资源，服务端采用python+flask编写，使用Servlet太麻烦了。关于Http协议的相关知识，可以在网上查看相关资料。代码比较简单，就不详细解释了。

1. 使用JDK中HttpURLConnection访问网络资源

public String executeHttpGet() {String result = null;URL url = null;HttpURLConnection connection = null;InputStreamReader in = null;try {url = new URL("http://10.0.2.2:8888/data/get/?token=alexzhou");connection = (HttpURLConnection) url.openConnection();in = new InputStreamReader(connection.getInputStream());BufferedReader bufferedReader = new BufferedReader(in);StringBuffer strBuffer = new StringBuffer();String line = null;while ((line = bufferedReader.readLine()) != null) {strBuffer.append(line);}result = strBuffer.toString();} catch (Exception e) {e.printStackTrace();} finally {if (connection != null) {connection.disconnect();}if (in != null) {try {in.close();} catch (IOException e) {e.printStackTrace();}}}return result;}

注意：因为是通过android模拟器访问本地pc服务端，所以不能使用localhost和127.0.0.1，使用127.0.0.1会访问模拟器自身。Android系统为实现通信将PC的IP设置为10.0.2.2

(2)post请求

public String executeHttpPost() {String result = null;URL url = null;HttpURLConnection connection = null;InputStreamReader in = null;try {url = new URL("http://10.0.2.2:8888/data/post/");connection = (HttpURLConnection) url.openConnection();connection.setDoInput(true);connection.setDoOutput(true);connection.setRequestMethod("POST");connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");connection.setRequestProperty("Charset", "utf-8");DataOutputStream dop = new DataOutputStream(connection.getOutputStream());dop.writeBytes("token=alexzhou");dop.flush();dop.close();in = new InputStreamReader(connection.getInputStream());BufferedReader bufferedReader = new BufferedReader(in);StringBuffer strBuffer = new StringBuffer();String line = null;while ((line = bufferedReader.readLine()) != null) {strBuffer.append(line);}result = strBuffer.toString();} catch (Exception e) {e.printStackTrace();} finally {if (connection != null) {connection.disconnect();}if (in != null) {try {in.close();} catch (IOException e) {e.printStackTrace();}}}return result;}

如果参数中有中文的话，可以使用下面的方式进行编码解码：

2.使用Apache的HttpClient访问网络资源
(1)get请求

public String executeGet() {String result = null;BufferedReader reader = null;try {HttpClient client = new DefaultHttpClient();HttpGet request = new HttpGet();request.setURI(new URI("http://10.0.2.2:8888/data/get/?token=alexzhou"));HttpResponse response = client.execute(request);reader = new BufferedReader(new InputStreamReader(response.getEntity().getContent()));StringBuffer strBuffer = new StringBuffer("");String line = null;while ((line = reader.readLine()) != null) {strBuffer.append(line);}result = strBuffer.toString();} catch (Exception e) {e.printStackTrace();} finally {if (reader != null) {try {reader.close();reader = null;} catch (IOException e) {e.printStackTrace();}}}return result;}

（2）post请求

public String executePost() {String result = null;BufferedReader reader = null;try {HttpClient client = new DefaultHttpClient();HttpPost request = new HttpPost();request.setURI(new URI("http://10.0.2.2:8888/data/post/"));List<NameValuePair> postParameters = new ArrayList<NameValuePair>();postParameters.add(new BasicNameValuePair("token", "alexzhou"));UrlEncodedFormEntity formEntity = new UrlEncodedFormEntity(postParameters);request.setEntity(formEntity);HttpResponse response = client.execute(request);reader = new BufferedReader(new InputStreamReader(response.getEntity().getContent()));StringBuffer strBuffer = new StringBuffer("");String line = null;while ((line = reader.readLine()) != null) {strBuffer.append(line);}result = strBuffer.toString();} catch (Exception e) {e.printStackTrace();} finally {if (reader != null) {try {reader.close();reader = null;} catch (IOException e) {e.printStackTrace();}}}return result;}

3.服务端代码实现
上面是采用两种方式的get和post请求的代码，下面来实现服务端的代码编写，使用python+flask真的非常的简单，就一个文件，前提是你得搭建好python+flask的环境，代码如下：

#coding=utf-8import json
from flask import Flask,request,render_templateapp = Flask(__name__)def send_ok_json(data=None):if not data:data = {}ok_json = {'ok':True,'reason':'','data':data}return json.dumps(ok_json)@app.route('/data/get/',methods=['GET'])
def data_get():token = request.args.get('token')ret = '%s**%s' %(token,'get')return send_ok_json(ret)@app.route('/data/post/',methods=['POST'])
def data_post():token = request.form.get('token')ret = '%s**%s' %(token,'post')return send_ok_json(ret)if __name__ == "__main__":app.run(host="localhost",port=8888,debug=True)

运行服务器，如图：

4. 编写单元测试代码
右击项目：new–》Source Folder取名tests，包名是：com.alexzhou.androidhttp.test（随便取，没有要求），结构如图：

在该包下创建测试类HttpTest，继承自AndroidTestCase。编写这四种方式的测试方法，代码如下:

public class HttpTest extends AndroidTestCase {@Overrideprotected void setUp() throws Exception {Log.e("HttpTest", "setUp");}@Overrideprotected void tearDown() throws Exception {Log.e("HttpTest", "tearDown");}public void testExecuteGet() {Log.e("HttpTest", "testExecuteGet");HttpClientTest client = HttpClientTest.getInstance();String result = client.executeGet();Log.e("HttpTest", result);}public void testExecutePost() {Log.e("HttpTest", "testExecutePost");HttpClientTest client = HttpClientTest.getInstance();String result = client.executePost();Log.e("HttpTest", result);}public void testExecuteHttpGet() {Log.e("HttpTest", "testExecuteHttpGet");HttpClientTest client = HttpClientTest.getInstance();String result = client.executeHttpGet();Log.e("HttpTest", result);}public void testExecuteHttpPost() {Log.e("HttpTest", "testExecuteHttpPost");HttpClientTest client = HttpClientTest.getInstance();String result = client.executeHttpPost();Log.e("HttpTest", result);}
}

附上HttpClientTest.java的其他代码：

public class HttpClientTest {private static final Object mSyncObject = new Object();
private static HttpClientTest mInstance;private HttpClientTest() {}public static HttpClientTest getInstance() {
synchronized (mSyncObject) {
if (mInstance != null) {
return mInstance;
}
mInstance = new HttpClientTest();
}
return mInstance;
}/**...上面的四个方法...*/
}

现在还需要修改Android项目的配置文件AndroidManifest.xml，添加网络访问权限和单元测试的配置，AndroidManifest.xml配置文件的全部代码如下：

<manifest xmlns:android="http://schemas.android.com/apk/res/android"package="com.alexzhou.androidhttp"android:versionCode="1"android:versionName="1.0" ><uses-permission android:name="android.permission.INTERNET" /><uses-sdkandroid:minSdkVersion="8"android:targetSdkVersion="15" /><applicationandroid:icon="@drawable/ic_launcher"android:label="@string/app_name"android:theme="@style/AppTheme" ><uses-library android:name="android.test.runner" /><activityandroid:name=".MainActivity"android:label="@string/title_activity_main" ><intent-filter><action android:name="android.intent.action.MAIN" /><category android:name="android.intent.category.LAUNCHER" /></intent-filter></activity></application><instrumentationandroid:name="android.test.InstrumentationTestRunner"android:targetPackage="com.alexzhou.androidhttp" /></manifest>

注意：
android:name=”android.test.InstrumentationTestRunner”这部分不用更改
android:targetPackage=”com.alexzhou.androidhttp”，填写应用程序的包名

5.测试结果
展开测试类HttpTest，依次选中这四个测试方法，右击：Run As–》Android Junit Test。
(1)运行testExecuteHttpGet，结果如图：

(2)运行testExecuteHttpPost，结果如图：

(3)运行testExecuteGet，结果如图：

(4)运行testExecutePost，结果如图：

转载请注明来自：Alex Zhou，本文链接：http://codingnow.cn/android/723.html