源码链接

package com.zhangbz.submitdata.Utils;

import java.io.ByteArrayOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import java.net.HttpURLConnection;

import java.net.MalformedURLException;

import java.net.URL;

import java.net.URLConnection;

import java.net.URLEncoder;

import android.util.Log;

public class NetUtils {

	private static final String TAG = "NetUtils";

	/**

	 * 使用post的方式登录

	 * @param userName

	 * @param password

	 * @return

	 */

	public static String loginOfPost(String userName, String password){

		HttpURLConnection conn = null;

		try {

			URL url = new URL("http://10.0.2.2:8080/serverzhangbz/servlet/LoginServlet?");

			conn = (HttpURLConnection) url.openConnection();

			conn.setRequestMethod("POST");

			conn.setReadTimeout(10000);  //连接的超时时间

			conn.setReadTimeout(5000);   //读数据的超时时间

			conn.setDoOutput(true);//必须设置此方法，允许输出

			//conn.setRequestProperty("content-Length", 234);  //设置请求头消息，可以设置多个

			//post请求的参数

			String data = "username=" + userName + "&password=" + password;

			//获得一个输出流，用于向服务器写数据，默认情况下，系统不予许向服务器输出内容

			OutputStream out = conn.getOutputStream();

			out.write(data.getBytes());

			out.flush();

			out.close();

			int responseCode = conn.getResponseCode();

			if(responseCode == 200) {

				InputStream is = conn.getInputStream();

				String state = getSringFromInputStream(is);

				Log.i(TAG, state);

				return state;

			} else {

				Log.i(TAG, "访问失败：" + responseCode);

			}

		} catch (Exception e) {

			// TODO Auto-generated catch block

			e.printStackTrace();

		}finally {

			if(conn != null) {

				conn.disconnect(); //关闭连接

			}

		}

		return null;

	}

	/**

	 * 使用get的方式登录

	 * @param userName

	 * @param password

	 * @return

	 */

	public static String logOfPost(String userName, String password) {

		HttpURLConnection conn = null; //局部变量在使用时必须进行初始化

		try {

			String data = "username=" + URLEncoder.encode(userName) + "&password=" + URLEncoder.encode(password);

			URL url = new URL("http://10.0.2.2:8080/serverzhangbz/servlet/LoginServlet?" + data);

			conn = (HttpURLConnection) url.openConnection();

			conn.setRequestMethod("GET");//get或者post必须得全大写

			conn.setReadTimeout(10000);//连接的超时时间

			conn.setReadTimeout(5000);//读数据的超时连接

			int responseCode = conn.getResponseCode();

			if(responseCode == 200) {

				InputStream is = conn.getInputStream();

				String state = getSringFromInputStream(is);

				Log.i(TAG, state);

				return state;

         		} else {

				Log.i(TAG, "访问失败：" + responseCode);

			}

		} catch (Exception e) {

			e.printStackTrace();

		} finally {

			if(conn != null) {

				conn.disconnect(); //关闭连接

			}

		}

		return null;

	}

	/**

	 * 根据流返回一个字符串信息

	 * @param is

	 * @return

	 * @throws IOException

	 */

	private static String getSringFromInputStream(InputStream is) throws IOException{

		ByteArrayOutputStream baos = new ByteArrayOutputStream();

		byte[] buffer = new byte[1024];

		int len = -1;

		while((len = is.read(buffer)) != -1){

			baos.write(buffer, 0, len);

		}

		is.close();

		String html = baos.toString(); //把流中的数据转换成字符串，采用的编码是：utf-8

		//String html = new String(baos.toByteArray(), "GBK");

		baos.close();

		return html;

	}

}