http请求 无响应，高手进

Question

为何没响应内容，难道是http请求内容不对吗？import java.net.*;
import java.io.*;
public class HTTPClient {
  String host="www.javathinker.org";
  int port=80;
  Socket socket;
  
  public void createSocket()throws Exception{
    socket=new Socket("www.163.com",80);
  }
    public void communicate()throws Exception{
  StringBuffer sb = new StringBuffer("GET / HTTP/1.1\r\n");
sb.append("Host: www.163.com\r\n");
sb.append("Connection: Keep-Alive\r\n");
sb.append("Accept: */*\r\n");    //发出HTTP请求
    OutputStream socketOut=socket.getOutputStream();
    socketOut.write(sb.toString().getBytes());
    socket.shutdownOutput();  //关闭输出流
       
    //接收响应结果
    System.out.println(socket);    InputStream socketIn=socket.getInputStream();
    BufferedReader br=new BufferedReader(new InputStreamReader(socketIn));
    String data;
    while((data=br.readLine())!=null){
      System.out.println(data);
    }
    socket.close();
  }
  
  public static void main(String args[])throws Exception{
    HTTPClient client=new HTTPClient();
    client.createSocket();
    client.communicate();
  } 
}

Answer 1

不是这样通信的吧
你想他返回什么呢？服务器端可能根本就没接受你的请求
自己写个服务器端就知道了他是怎么接受的我想LZ是想抓取页面吗？
public static void main(String[] a) throws UnknownHostException, IOException{
String sLine = "";
InputStream in;
java.net.URL url = new java.net.URL("http://www.google.cn/"); HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.connect();
in = connection.getInputStream(); BufferedReader reader = new BufferedReader(new java.io.InputStreamReader(in)); while ((sLine = reader.readLine()) != null)
{
 System.out.println(sLine);
}

}

Answer 2

package test;import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLEncoder;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;import org.apache.log4j.Logger;/**
 * <pre>
 * HTTP请求代理类
 * </pre>
 * 
 * @author benl
 * @version 1.0, 2007-7-3
 */
public class HttpRequestProxy
{
    /**
     * 连接超时
     */
    private static int connectTimeOut = 5000;    /**
     * 读取数据超时
     */
    private static int readTimeOut = 10000;    /**
     * 请求编码
     */
    private static String requestEncoding = "GBK";    private static Logger logger = Logger.getLogger(HttpRequestProxy.class);    /**
     * <pre>
     * 发送带参数的GET的HTTP请求
     * </pre>
     * 
     * @param reqUrl HTTP请求URL
     * @param parameters 参数映射表
     * @return HTTP响应的字符串
     */
    public static String doGet(String reqUrl, Map parameters,
            String recvEncoding)
    {
        HttpURLConnection url_con = null;
        String responseContent = null;
        try
        {
            StringBuffer params = new StringBuffer();
            for (Iterator iter = parameters.entrySet().iterator(); iter
                    .hasNext();)
            {
                Entry element = (Entry) iter.next();
                params.append(element.getKey().toString());
                params.append("=");
                params.append(URLEncoder.encode(element.getValue().toString(),
                        HttpRequestProxy.requestEncoding));
                params.append("&");
            }            if (params.length() > 0)
            {
                params = params.deleteCharAt(params.length() - 1);
            }            URL url = new URL(reqUrl);
            url_con = (HttpURLConnection) url.openConnection();
            url_con.setRequestMethod("GET");
            System.setProperty("sun.net.client.defaultConnectTimeout", String
                    .valueOf(HttpRequestProxy.connectTimeOut));// （单位：毫秒）jdk1.4换成这个,连接超时
            System.setProperty("sun.net.client.defaultReadTimeout", String
                    .valueOf(HttpRequestProxy.readTimeOut)); // （单位：毫秒）jdk1.4换成这个,读操作超时
            // url_con.setConnectTimeout(5000);//（单位：毫秒）jdk
            // 1.5换成这个,连接超时
            // url_con.setReadTimeout(5000);//（单位：毫秒）jdk 1.5换成这个,读操作超时
            url_con.setDoOutput(true);
            byte[] b = params.toString().getBytes();
            url_con.getOutputStream().write(b, 0, b.length);
            url_con.getOutputStream().flush();
            url_con.getOutputStream().close();            InputStream in = url_con.getInputStream();
            BufferedReader rd = new BufferedReader(new InputStreamReader(in,
                    recvEncoding));
            String tempLine = rd.readLine();
            StringBuffer temp = new StringBuffer();
            String crlf=System.getProperty("line.separator");
            while (tempLine != null)
            {
                temp.append(tempLine);
                temp.append(crlf);
                tempLine = rd.readLine();
            }
            responseContent = temp.toString();
            rd.close();
            in.close();
        }
        catch (IOException e)
        {
            logger.error("网络故障", e);
        }
        finally
        {
            if (url_con != null)
            {
                url_con.disconnect();
            }
        }        return responseContent;
    }    /**
     * <pre>
     * 发送不带参数的GET的HTTP请求
     * </pre>
     * 
     * @param reqUrl HTTP请求URL
     * @return HTTP响应的字符串
     */

Answer 3

   public static String doGet(String reqUrl, String recvEncoding)
    {
        HttpURLConnection url_con = null;
        String responseContent = null;
        try
        {
            StringBuffer params = new StringBuffer();
            String queryUrl = reqUrl;
            int paramIndex = reqUrl.indexOf("?");            if (paramIndex > 0)
            {
                queryUrl = reqUrl.substring(0, paramIndex);
                String parameters = reqUrl.substring(paramIndex + 1, reqUrl
                        .length());
                String[] paramArray = parameters.split("&");
                for (int i = 0; i < paramArray.length; i++)
                {
                    String string = paramArray[i];
                    int index = string.indexOf("=");
                    if (index > 0)
                    {
                        String parameter = string.substring(0, index);
                        String value = string.substring(index + 1, string
                                .length());
                        params.append(parameter);
                        params.append("=");
                        params.append(URLEncoder.encode(value,
                                HttpRequestProxy.requestEncoding));
                        params.append("&");
                    }
                }                params = params.deleteCharAt(params.length() - 1);
            }            URL url = new URL(queryUrl);
            url_con = (HttpURLConnection) url.openConnection();
            url_con.setRequestMethod("GET");
            System.setProperty("sun.net.client.defaultConnectTimeout", String
                    .valueOf(HttpRequestProxy.connectTimeOut));// （单位：毫秒）jdk1.4换成这个,连接超时
            System.setProperty("sun.net.client.defaultReadTimeout", String
                    .valueOf(HttpRequestProxy.readTimeOut)); // （单位：毫秒）jdk1.4换成这个,读操作超时
            // url_con.setConnectTimeout(5000);//（单位：毫秒）jdk
            // 1.5换成这个,连接超时
            // url_con.setReadTimeout(5000);//（单位：毫秒）jdk 1.5换成这个,读操作超时
            url_con.setDoOutput(true);
            byte[] b = params.toString().getBytes();
            url_con.getOutputStream().write(b, 0, b.length);
            url_con.getOutputStream().flush();
            url_con.getOutputStream().close();
            InputStream in = url_con.getInputStream();
            BufferedReader rd = new BufferedReader(new InputStreamReader(in,
                    recvEncoding));
            String tempLine = rd.readLine();
            StringBuffer temp = new StringBuffer();
            String crlf=System.getProperty("line.separator");
            while (tempLine != null)
            {
                temp.append(tempLine);
                temp.append(crlf);
                tempLine = rd.readLine();
            }
            responseContent = temp.toString();
            rd.close();
            in.close();
        }
        catch (IOException e)
        {
            logger.error("网络故障", e);
        }
        finally
        {
            if (url_con != null)
            {
                url_con.disconnect();
            }
        }        return responseContent;
    }    /**
     * <pre>
     * 发送带参数的POST的HTTP请求
     * </pre>
     * 
     * @param reqUrl HTTP请求URL
     * @param parameters 参数映射表
     * @return HTTP响应的字符串
     */
    public static String doPost(String reqUrl, Map parameters,
            String recvEncoding)
    {
        HttpURLConnection url_con = null;
        String responseContent = null;
        try
        {
            StringBuffer params = new StringBuffer();
            for (Iterator iter = parameters.entrySet().iterator(); iter
                    .hasNext();)
            {
                Entry element = (Entry) iter.next();
                params.append(element.getKey().toString());
                params.append("=");
                params.append(URLEncoder.encode(element.getValue().toString(),
                        HttpRequestProxy.requestEncoding));
                params.append("&");
            }            if (params.length() > 0)
            {
                params = params.deleteCharAt(params.length() - 1);
            }            URL url = new URL(reqUrl);
            url_con = (HttpURLConnection) url.openConnection();
            url_con.setRequestMethod("POST");
            System.setProperty("sun.net.client.defaultConnectTimeout", String
                    .valueOf(HttpRequestProxy.connectTimeOut));// （单位：毫秒）jdk1.4换成这个,连接超时
            System.setProperty("sun.net.client.defaultReadTimeout", String
                    .valueOf(HttpRequestProxy.readTimeOut)); // （单位：毫秒）jdk1.4换成这个,读操作超时
            // url_con.setConnectTimeout(5000);//（单位：毫秒）jdk
            // 1.5换成这个,连接超时
            // url_con.setReadTimeout(5000);//（单位：毫秒）jdk 1.5换成这个,读操作超时
            url_con.setDoOutput(true);
            byte[] b = params.toString().getBytes();
            url_con.getOutputStream().write(b, 0, b.length);
            url_con.getOutputStream().flush();
            url_con.getOutputStream().close();            InputStream in = url_con.getInputStream();
            BufferedReader rd = new BufferedReader(new InputStreamReader(in,
                    recvEncoding));
            String tempLine = rd.readLine();
            StringBuffer tempStr = new StringBuffer();
            String crlf=System.getProperty("line.separator");
            while (tempLine != null)
            {
                tempStr.append(tempLine);
                tempStr.append(crlf);
                tempLine = rd.readLine();
            }
            responseContent = tempStr.toString();
            rd.close();
            in.close();
        }
        catch (IOException e)
        {
            logger.error("网络故障", e);
        }
        finally
        {
            if (url_con != null)
            {
                url_con.disconnect();
            }
        }
        return responseContent;
    }    /**
     * @return 连接超时(毫秒)
     * @see com.hengpeng.common.web.HttpRequestProxy#connectTimeOut
     */
    public static int getConnectTimeOut()
    {
        return HttpRequestProxy.connectTimeOut;
    }    /**
     * @return 读取数据超时(毫秒)
     * @see com.hengpeng.common.web.HttpRequestProxy#readTimeOut
     */
    public static int getReadTimeOut()
    {
        return HttpRequestProxy.readTimeOut;
    }    /**
     * @return 请求编码
     * @see com.hengpeng.common.web.HttpRequestProxy#requestEncoding
     */
    public static String getRequestEncoding()
    {
        return requestEncoding;
    }    /**
     * @param connectTimeOut 连接超时(毫秒)
     * @see com.hengpeng.common.web.HttpRequestProxy#connectTimeOut
     */
    public static void setConnectTimeOut(int connectTimeOut)
    {
        HttpRequestProxy.connectTimeOut = connectTimeOut;
    }    /**
     * @param readTimeOut 读取数据超时(毫秒)
     * @see com.hengpeng.common.web.HttpRequestProxy#readTimeOut
     */
    public static void setReadTimeOut(int readTimeOut)
    {
        HttpRequestProxy.readTimeOut = readTimeOut;
    }    /**
     * @param requestEncoding 请求编码
     * @see com.hengpeng.common.web.HttpRequestProxy#requestEncoding
     */
    public static void setRequestEncoding(String requestEncoding)
    {
        HttpRequestProxy.requestEncoding = requestEncoding;
    }
    
    public static void main(String[] args)
    {
        Map map = new HashMap();
//        map.put("_RECONNECT", "YES");
//        map.put("_FUNCTION", "WWW_GET_REPORT");
//        map.put("_REPORT", "RM07MLBS");
//        map.put("SELC_WERKS-LOW", "V001");
//        map.put("SELC_MATNR-LOW", "10000001");
//       
        String temp = HttpRequestProxy.doPost("http://lhaig:82/scripts/wgate/xgwfc/!?_FUNCTION=WWW_GET_SELSCREEN&_REPORT=RM07MLBS", map, "UTF-8");
        System.out.println("返回的消息是:"+temp);
        
    }
}

Answer 4

我主要是想看看 http请求发送的内容，虽然都有介绍，但是没跑通过。

Answer 5

String temp = HttpRequestProxy.doPost("http://163.com", map, "UTF-8"); 

Answer 6

知道哪里错了 
sb.append("Accept: */*\r\n\r\n");消息的最后一行在加个回车，发到自己建的tomcat服务 可以返回正常数据了。但是像访问163，baidu,google等都没反应，可能做了什么过滤。不知道 望哪个达人帮忙解答，谢谢。

Answer 7

sunxing007的一个代码可以读到百度的页面。
package socket;import java.io.*;
import java.net.*;public class MyHttpClient {
public static void main(String[] args) throws Exception{
InetAddress inet = InetAddress.getByName("www.baidu.com");
System.out.println(inet.getHostAddress());
Socket socket = new Socket(inet.getHostAddress(),80);
InputStream in = socket.getInputStream();
OutputStream out = socket.getOutputStream();
BufferedReader reader = new BufferedReader(new InputStreamReader(in));
PrintWriter writer = new PrintWriter(out);
writer.println("GET /home.html HTTP/1.1");//home.html是关于百度的页面
writer.println("Accept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, application/x-shockwave-flash, application/xaml+xml, application/vnd.ms-xpsdocument, application/x-ms-xbap, application/x-ms-application, application/msword, application/vnd.ms-excel, application/vnd.ms-powerpoint, */*");
writer.println("Accept-Language: en-us,zh-cn;q=0.5");
writer.println("Accept-Encoding: gzip, deflate");
writer.println("Host: www.baidu.com");
writer.println("User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.04506.30; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)");
writer.println("Connection: Keep-Alive");
writer.println();
writer.flush();
String line = reader.readLine();
while(line!=null){
System.out.println(line);
line = reader.readLine();
}
reader.close();
writer.close();
}
}你看看是不是你要的效果。

Answer 8

呵呵，你对协议没有理解透；
看看这一句
 sb.append("Accept: */*\r\n");后面增加一句就行了
 sb.append("\r\n");因为http协议的头(header)，是以空行作为结束标记的。OVER,建议你再去看看http的协议。