Android客戶端和服務器端數據交互的第二種方法

網上有很多例子來演示Android客戶端和服務器端數據如何實現交互不過這些例子大多比較繁雜，對於初學者來說這是不利的，現在介紹幾種代碼簡單、邏輯清晰的交互例子，本篇博客介紹第二種：

一、服務器端：

代碼1：添加名為“AndroidServerServlet.java”的文件

package com.ghj.packageofservlet;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class AndroidServerServlet extends HttpServlet {

	private static final long serialVersionUID = 6792396567928634227L;

	public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {
		response.setContentType(text/plain; charset=UTF-8);
		request.setCharacterEncoding(UTF-8);
		System.err.println(request.getParameter(clientData));
		PrintWriter printWriter = response.getWriter();
		printWriter.print(您好Android客戶端！);
		printWriter.flush();
		printWriter.close();
	}
}

代碼2：修改名為“web.xml”的文件

		AndroidServerServlet
		com.ghj.packageofservlet.AndroidServerServlet
	

	
		AndroidServerServlet
		/AndroidServerServlet
	

二、Android手機客戶端：

代碼1：添加名為“AndroidClientActivity.java”的文件

package com.example.androidclient;

import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.List;

import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
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.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Toast;

public class AndroidClientActivity extends Activity {
	
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.android_client);

		Button sendButton = (Button) findViewById(R.id.send_button);
		sendButton.setOnClickListener(new OnClickListener(){
			@Override
			public void onClick(View v) {
				new Thread(new Runnable(){
				    @Override
				    public void run() {
				    	HttpPost httpRequest = new HttpPost(http://172.16.99.207:8080/AndroidServer/AndroidServerServlet);
			    		List params = new ArrayList();
			    		params.add(new BasicNameValuePair(clientData, 您好服務器端！));
			    		try {
			    			Message message = new Message();
		                    Bundle bundle = new Bundle();
			    			httpRequest.setEntity(new UrlEncodedFormEntity(params, HTTP.UTF_8));//設置請求參數項
			                HttpClient httpClient = new DefaultHttpClient();
			                HttpResponse httpResponse = httpClient.execute(httpRequest);//執行請求返回響應
			                if(httpResponse.getStatusLine().getStatusCode() == 200){//判斷是否請求成功
			                    bundle.putString(msg, EntityUtils.toString(httpResponse.getEntity()));
			                }else{
			                	bundle.putString(msg, 沒有獲取到Android服務器端的響應！);
			                }
			                message.setData(bundle);
		                    handler.sendMessage(message);
			            } catch (ClientProtocolException e) {
			            	e.printStackTrace();
			    		} catch (UnsupportedEncodingException e) {
			    			e.printStackTrace();
			    		} catch (IOException e) {
			    			e.printStackTrace();
			    		}
				    }
				}).start();
			}
		});
	}
	
	private Handler handler = new Handler(){
		@Override
		public void handleMessage(Message message) {
			super.handleMessage(message);
	        Bundle bundle = message.getData();
	        String msg = bundle.getString(msg);
			Toast.makeText(getApplicationContext(), msg, Toast.LENGTH_LONG).show();
		}
	};
}