Android - 向服务器发送数据(POST) - HTTPClient.
该篇文章主要说明使用Apache提供的HTTPClient,通过post方式,向服务器发送数据.由于有些东西在 Android - 向服务器发送数据(GET) 中提到过,就不再重复.
一,Android客户端的业务逻辑层:
package spt.http.post;
import java.io.IOException;
import java.net.MalformedURLException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import org.apache.http.HttpResponse;
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 android.os.Handler;
import android.util.Log;
/**
* 用户向服务器端发送数据的类(使用post)方法.
*
* @author Administrator
*
*/
public class PostSender {
// 连接服务器的url.
private static final String URL = "http://192.168.1.101:8080/ReceiveAndroid/ServletForPostMethod";
// 标识是否连接到服务器成功.
public static final int SEND_SUCCESS = 1;
public static final int SEND_FAIL = 0;
private Handler handler = null; //新线程关联的Handler,用于将是否发送成功的标识Message放到消息队列中.
public PostSender(Handler handler) {
this.handler = handler;
}
/**
* 往服务器发送数据.
*
* @param name
* @param pwd
*/
public void send(String name, String pwd) {
// 这里params要传递到另外一个方法,加final为了防止被修改.
final Map<String, String> params = new HashMap<String, String>();
params.put("name", name);
params.put("pwd", pwd);
// 启动新的线程连接服务器.
new Thread(new Runnable() {
@Override
public void run() {
// 请求连接.
try {
if (postSend(params, URL, "utf-8"))
handler.sendEmptyMessage(SEND_SUCCESS);
else
handler.sendEmptyMessage(SEND_FAIL);
} catch (MalformedURLException e) {
Log.d("sysout", "run:MalformedURLException" + e.getMessage());
} catch (IOException e) {
Log.d("sysout", "run:IOException" + e.getMessage());
}
}
}).start();
}
/**
* 发送post请求的方法.
*
* @param params
* 请求参数的键-值对.
* @param url
* @param encoding
* 使用指定编码对参数值进行编码.
* @return
* @throws MalformedURLException
* @throws IOException
*/
private boolean postSend(Map<String, String> params, String url,
String encoding) throws MalformedURLException, IOException {
// 封装请求参数的键值对.
List<BasicNameValuePair> pairs = new ArrayList<BasicNameValuePair>();
for (Entry<String, String> param : params.entrySet()) {
pairs.add(new BasicNameValuePair(param.getKey(), param.getValue()));
}
//封装请求参数的实体.
UrlEncodedFormEntity entity = new UrlEncodedFormEntity(pairs, encoding);
//使用post请求.
HttpPost post = new HttpPost(url);
post.setEntity(entity);
//使用DefaultHttpClient指定请求,以获取响应信息.
DefaultHttpClient client = new DefaultHttpClient();
HttpResponse response = client.execute(post);
return response.getStatusLine().getStatusCode() == 200; // 等于200表示发送成功.
}
}
二,服务器端的Servlet,重写doPost方法:
package spt.servlet;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
@WebServlet("/ServletForPostMethod")
public class ServletForPostMethod extends HttpServlet{
/**
*
*/
private static final long serialVersionUID = 1L;
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
System.out.println("enter...post");
String name = req.getParameter("name");
String pwd = req.getParameter("pwd");
System.out.println("name=" + name);
System.out.println("pwd=" + pwd);
}
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
// System.out.println("enter...get");
// String name = req.getParameter("name");
// String pwd = req.getParameter("pwd");
// System.out.println("name=" + name);
// System.out.println("pwd=" + pwd);
}
}
另外,途中,我连几个小时的Tomcat服务器,后来通过log过滤,发现自己的问题,所以建议多使用log捕获异常信息.我在网上看到有位网友,使用HTTP进行post连接的时候,对url的处理和get一样,都是将参数拼接在原有url的后面,我觉得很奇怪.