使用ＨＴＴＰ协议访问网络

有两种方法分别是 HttpURLConnection 和HttpClient

使用HttpURLConnection

xml界面代码：

<span style="font-size:14px;"><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.example.networktest.MainActivity"
    android:orientation="vertical"
    >

    <Button
        android:id="@+id/send_request"
        android:layout_height="wrap_content"
        android:layout_width="match_parent"
        android:text="Send Request"
        />

    <ScrollView
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        >
		<TextView
		    android:id="@+id/respose_text"
		    android:layout_width="fill_parent"
		    android:layout_height="wrap_content"
		    />
    </ScrollView>

</LinearLayout></span>

MainActivity中的代码：

<span style="font-size:14px;">package com.example.networktest;

import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;

public class MainActivity extends Activity implements OnClickListener {

	private TextView tv_response;
	protected static final int SHOW_RESPONSE = 0;
	private Handler handler  = new Handler(){
		@Override
		public void handleMessage(Message msg) {
			switch (msg.what) {
			case SHOW_RESPONSE:
				String response = (String) msg.obj;
				tv_response.setText(response);
				break;

			default:
				break;
			}

		}

	};

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);

		tv_response = (TextView) findViewById(R.id.respose_text);
		Button btn_send = (Button) findViewById(R.id.send_request);
		btn_send.setOnClickListener(this);

	}

	@Override
	public void onClick(View v) {
		if(v.getId()==R.id.send_request){
			sendRequestWithHttpURLConnection();
		}
	}

	private void sendRequestWithHttpURLConnection() {
		//开启线程发起网络请求
		new Thread(new Runnable() {

			@Override
			public void run() {
				HttpURLConnection conn = null;
				try{
					URL url = new URL("http://192.168.1.101/AndroidLogin/servlet/LoginServlet?userName=dumas&passWord=1213");
					conn = (HttpURLConnection) url.openConnection();

					conn.setRequestMethod("GET");
					conn.setReadTimeout(8000);
					conn.setConnectTimeout(8000);

					//对获取到的输入流进行读取
					InputStream is = conn.getInputStream();
					BufferedReader reader = new BufferedReader(new InputStreamReader(is));

					StringBuilder response = new StringBuilder();
					String line;
					while((line= reader.readLine())!=null){
						response.append(line);
					}

					Message message = new Message();
					message.what = SHOW_RESPONSE;
					message.obj = response.toString();

				    handler.sendMessage(message);

				}catch(Exception e){
					e.printStackTrace();
				}finally{
					if(conn!=null){
						conn.disconnect();
					}
				}

			}
		}).start();
	}
}</span>

注意还要添加权限：

 <uses-permission android:name="android.permission.INTERNET"/>

以上是使用GET提交的，假如使用ＰＯＳＴ则如下：

<span style="font-size:14px;">private void sendRequestWithHttpURLConnection() {
		//开启线程发起网络请求
		new Thread(new Runnable() {

			@Override
			public void run() {
				HttpURLConnection conn = null;
				try{
					URL url = new URL("http://192.168.1.101/AndroidLogin/servlet/LoginServlet");
					conn = (HttpURLConnection) url.openConnection();

					conn.setRequestMethod("POST");
					conn.setReadTimeout(8000);
					conn.setConnectTimeout(8000);

					//－－－向服务器提交姓名和密码
					DataOutputStream daos = new DataOutputStream(conn.getOutputStream());
					daos.writeBytes("userName=duams&passWord=123");

					//对获取到的输入流进行读取
					InputStream is = conn.getInputStream();
					BufferedReader reader = new BufferedReader(new InputStreamReader(is));

					StringBuilder response = new StringBuilder();
					String line;
					while((line= reader.readLine())!=null){
						response.append(line);
					}
					</span>

使用HttpClient

是用Get方式提交数据

<span style="font-size:14px;">public void run() {
				HttpURLConnection conn = null;
				try{

					//使用Get方式提交数据
					HttpClient httpClient = new DefaultHttpClient();
					HttpGet httpGet = new HttpGet("http://192.168.1.101/AndroidLogin/servlet/LoginServlet?userName=dumas&passWord=123"<span style="white-space: pre; ">					</span>);
					HttpResponse httpReponse = httpClient.execute(httpGet);

					if(httpReponse.getStatusLine().getStatusCode()==200){
						HttpEntity entity = httpReponse.getEntity();
						response = EntityUtils.toString(entity,"utf-8");
					}

					Message message = new Message();
					message.what = SHOW_RESPONSE;
					message.obj = response.toString();

				    handler.sendMessage(message);

				}catch(Exception e){
					e.printStackTrace();
				}finally{
					if(conn!=null){
						conn.disconnect();
					}
				}

			}
		}).start();
	}</span>

使用POST方式提交

	private void sendRequestWithHttpURLConnection() {
		//开启线程发起网络请求
		new Thread(new Runnable() {

			private String response;

			@Override
			public void run() {
				HttpURLConnection conn = null;
				try{

					//使用Get方式提交数据
					HttpClient httpClient = new DefaultHttpClient();
					HttpPost httpPost = new HttpPost("http://192.168.1.101/AndroidLogin/servlet/LoginServlet");

					List<NameValuePair> params = new ArrayList<NameValuePair>();
					params.add(new BasicNameValuePair("userName", "dumas"));
					params.add(new BasicNameValuePair("passWord", "123"));
					UrlEncodedFormEntity entity = new UrlEncodedFormEntity(params,"utf-8");

					httpPost.setEntity(entity);

					HttpResponse httpResponse = httpClient.execute(httpPost);

					if(httpResponse.getStatusLine().getStatusCode()==200){
						HttpEntity httpEntity = httpResponse.getEntity();
						response = EntityUtils.toString(httpEntity, "utf-8");
					}

					Message message = new Message();
					message.what = SHOW_RESPONSE;
					message.obj = response.toString();

				    handler.sendMessage(message);

				}catch(Exception e){
					e.printStackTrace();
				}finally{
					if(conn!=null){
						conn.disconnect();
					}
				}

			}
		}).start();
	}