Jakarta的HttpClient API 模拟get/post

最近搞一个扣网页内容的SessionBean，需要模拟客户端post提交，然后得到servlet返回的结果。
采用Jakarta的HttpClient API解决之.
HttpClient扩展和增强了标准java.net包，是一个内容广泛的代码库，功能极其丰富，能够构造出各
种使用HTTP协议的分布式应用，或者也可以嵌入到现有应用，为应用增加访问HTTP协议的能力

要求：
1：CLASSPATH中有commons-httpclient.jar，common-logging.jar
2：确保%JAVA_HOME% /jre/lib/security/java.security文件包含这行代码：
security.provider.2= com.sun.net.ssl.internal.ssl.Provider。

一:GET方法测试代码:

 /* 
 * Created on Sep 25, 2006
 *
 * To change the template for this generated file go to
 * Window>Preferences>Java>Code Generation>Code and Comments
  */ 
 package  co.iproxy.http;

 import  java.io.IOException;

 import  org.apache.commons.httpclient.HttpClient;
 import  org.apache.commons.httpclient.HttpException;
 import  org.apache.commons.httpclient.HttpStatus;
 import  org.apache.commons.httpclient.methods.GetMethod;

 /** */ /** 
 *  @author  lichunlei
 *
 * To change the template for this generated type comment go to
 * Window>Preferences>Java>Code Generation>Code and Comments
  */ 
 public   class  HttpClientGetMethodTest
 ... {

  public   static   void  main(String[] args)
  ... {
  HttpClient client  =   new  HttpClient();
  String url  =   " http://192.168.0.79:9080/Icare/IcareTest/index.jsp " ;
  GetMethod method  =   new  GetMethod(url);

   try 
    ... {
   client.executeMethod(method);
    if  (method.getStatusCode()  ==  HttpStatus.SC_OK)
    ... {
    String response  =  method.getResponseBodyAsString();
    System.out.println(response);
   } 
 
  } 
   catch  (HttpException e)
   ... {
   e.printStackTrace();

  } 
   catch  (IOException e)
   ... {
   e.printStackTrace();
  } 
   finally 
    ... {

   method.releaseConnection();
   method.recycle();
  } 
 
 } 
} 

二:POST方法测试代码:

 /**/ /* 
 * Created on Sep 25, 2006
 *
 * To change the template for this generated file go to
 * Window>Preferences>Java>Code Generation>Code and Comments
  */ 
 package  co.iproxy.http;

 import  java.io.BufferedReader;
 import  java.io.ByteArrayInputStream;
 import  java.io.File;
 import  java.io.FileNotFoundException;
 import  java.io.FileReader;
 import  java.io.IOException;
 import  java.io.InputStream;

 import  org.apache.commons.httpclient.DefaultMethodRetryHandler;
 import  org.apache.commons.httpclient.HostConfiguration;
 import  org.apache.commons.httpclient.HttpClient;
 import  org.apache.commons.httpclient.HttpStatus;
 import  org.apache.commons.httpclient.methods.PostMethod;

 /** */ /** 
 *  @author  lichunlei
 *
 * To change the template for this generated type comment go to
 * Window>Preferences>Java>Code Generation>Code and Comments
  */ 
 public   class  HttpClientPostMethodTest
 ... {

  static   int  BASE_BODY_SIZE  =   10240 ;
  static   int  INC_BODY_SIZE  =   51200 ;

  public   static   void  main(String[] args)
  ... {

  String request  =   null ;
  String url  =   " http://132.201.69.80:5080/BISWeb/Servicelet " ;
  String result  =   null ;

  String filePath  =   " D:/OPS_piese_idl36(from cvs)/Ntelagent/co/iproxy/http/request.txt " ;
  File f  =   new  File(filePath);
  FileReader fileReader  =   null ;
   try 
    ... {
   fileReader  =   new  FileReader(f);
   BufferedReader bufferedReader  =   new  BufferedReader(fileReader);
   String currentLine;
   StringBuffer content  =   new  StringBuffer();
    while  ((currentLine  =  bufferedReader.readLine())  !=   null )
    ... {
    content.append(currentLine);
   } 
   request  =  content.toString();
  } 
   catch  (Exception e1)
   ... {
    //  TODO Auto-generated catch block 
    e1.printStackTrace();
  } 
 
  System.out.println( " the request is:  "   +  request);

  DefaultMethodRetryHandler retryhandler  =   new  DefaultMethodRetryHandler();
  retryhandler.setRequestSentRetryEnabled( true );
  retryhandler.setRetryCount( 2 );  //  retry 2 times 
 
  HttpClient httpClient  =   new  HttpClient();
  PostMethod method  =   new  PostMethod(url);

  InputStream data  =   new  ByteArrayInputStream(request.getBytes());
  method.setRequestBody(data);

  method.setFollowRedirects( true );
  method.setMethodRetryHandler(retryhandler);

   try 
    ... {

    //  execute the method 
    HostConfiguration cf  =   new  HostConfiguration();
   System.out.println( " use proxy " );
   cf.setProxy( " 192.168.254.212 " ,  4480 );
   httpClient.setHostConfiguration(cf);
    // httpClient.setTimeout(10000000); 
 
    int  retcode  =  httpClient.executeMethod(method);

    if  (retcode  ==  HttpStatus.SC_OK)
    ... {
     byte [] responseBody  =   new   byte [BASE_BODY_SIZE];
    java.io.InputStream istream  =  method.getResponseBodyAsStream();
     int  npos  =   0 ;
     int  nread  =   0 ;
     while  ((nread  =  istream.read(responseBody, npos, responseBody.length  -  npos))  >=   0 )
     ... {
     npos  +=  nread;
      if  (npos  >=  responseBody.length)
      ... {
       byte [] tmpBuf  =   new   byte [npos  +  INC_BODY_SIZE];
      System.arraycopy(responseBody,  0 , tmpBuf,  0 , npos);
      responseBody  =  tmpBuf;
     } 
    } 
 
    result  =   new  String(responseBody,  0 , npos);
   } 
    else 
     ... {
     throw   new  IOException( " failed to send request: retcode:  "   +  retcode);
   } 
 
  } 
   catch  (Exception e)
   ... {
  } 
   finally 
    ... {
   System.out.println( " lcl test in httpClient: "   +  result);

  } 
 
 } 
} 

以上两个class已经包含了大部分常用的模拟http客户端的技术了,包括设置代理服务器,提交表单,得到返回结果等.
通过上面的测试代码,已经可以初步解决扣网页的问题了.现在备份一下我的实现方法(不是很通用,需要进一步完善), 同时也供大家参考.

/**/ /* 
 * Created on Sep 25, 2006
 *
 * To change the template for this generated file go to
 * Window>Preferences>Java>Code Generation>Code and Comments
  */ 
 package  co.iproxy.http;

 import  java.io.ByteArrayInputStream;
 import  java.io.IOException;
 import  java.io.InputStream;

 import  java.net.MalformedURLException;

 import  org.apache.commons.httpclient.DefaultMethodRetryHandler;
 import  org.apache.commons.httpclient.HostConfiguration;
 import  org.apache.commons.httpclient.HttpClient;
 import  org.apache.commons.httpclient.HttpStatus;
 import  org.apache.commons.httpclient.methods.PostMethod;

 /** */ /** 
 *  @author  lichunlei
 *
 * To change the template for this generated type comment go to
 * Window>Preferences>Java>Code Generation>Code and Comments
  */ 
  public   class  HttpService  implements  ServiceInterface  ... {

  private  HttpClient httpClient  =   new  HttpClient();

  private  DefaultMethodRetryHandler retryhandler  =   null ;

  private  String url  =   null ;

  static   int  BASE_BODY_SIZE  =   10240 ;
  static   int  INC_BODY_SIZE  =   51200 ;

  public  HttpService()  throws  MalformedURLException  ... {
   this .createMethodRetryHandler();
   this .setHostConfiguration();
 } 
 
   private   void  createMethodRetryHandler()  ... {
  retryhandler  =   new  DefaultMethodRetryHandler();
  retryhandler.setRequestSentRetryEnabled( true );
  retryhandler.setRetryCount( 2 );  //  retry 2 times 
  } 
 
   private   void  setHostConfiguration()  throws  MalformedURLException  ... {
   this .url  =   " http://132.201.69.80:5080/BISWeb/Servicelet " ;
  String host  =   " 132.201.69.80 " ;
   int  port  =   5080 ;

  String protocol  =   " http " ;

   if  (url  !=   null   &&   ! url.trim().equals( "" ))  ... {
   java.net.URL nurl  =   new  java.net.URL(url);
   host  =  nurl.getHost();
   port  =  nurl.getPort();
   protocol  =  nurl.getProtocol();
  } 
 
  setHostConfiguration(host, port, protocol);
 } 
 
   /** */ /** 
  * Set host configuration
  *
  *  @param  host host name/ip
  *  @param  port port number
  *  @param  protocol protocol name (e.g. "jakarta.apache.org" )
   */ 
   private   void  setHostConfiguration(String host,  int  port, String protocol)  ... {
   //  Set the default host/protocol for the methods to connect to.
   //  This value will only be used if the methods are not given an absolute URI 
   httpClient.getHostConfiguration().setHost(
   ((host  ==   null   ||  host.trim().equals( "" ))  ?   " localhost "  : host),
   (port  <=   0   ?   80  : port),
   ((protocol  ==   null   ||  protocol.trim().equals( "" ))
     ?   " http " 
    : protocol));
 } 
 
   public  String process(String request)  throws  IOException  ... {
  String result  =   null ;
  PostMethod method  =   new  PostMethod(url);

  InputStream data  =   new  ByteArrayInputStream(request.getBytes());
  method.setRequestBody(data);
  method.setFollowRedirects( true );
  method.setMethodRetryHandler(retryhandler);

   try   ... {
    //  execute the method 
    HostConfiguration cf  =   new  HostConfiguration();
   System.out.println( " use proxy " );
   cf.setProxy( " 192.168.254.212 " ,  4480 );
   httpClient.setHostConfiguration(cf);
    // httpClient.setTimeout(10000000); 
     int  retcode  =  httpClient.executeMethod(method);
    if  (retcode  ==  HttpStatus.SC_OK)  ... {
     byte [] responseBody  =   new   byte [BASE_BODY_SIZE];
     //  byte[] responseBody = body; 
 
    java.io.InputStream istream  =  method.getResponseBodyAsStream();
     int  npos  =   0 ;
     int  nread  =   0 ;
     while  ((nread  = 
     istream.read(
      responseBody,
      npos,
      responseBody.length  -  npos))
      >=   0 )  ... {
     npos  +=  nread;
      if  (npos  >=  responseBody.length)  ... {
       byte [] tmpBuf  =   new   byte [npos  +  INC_BODY_SIZE];
      System.arraycopy(responseBody,  0 , tmpBuf,  0 , npos);
      responseBody  =  tmpBuf;
     } 
    } 
 
     //  byte[] responseBody = method.getResponseBody(); 
     result  =   new  String(responseBody,  0 , npos);
   }   else   ... {
     throw   new  IOException(
      " failed to send request: retcode:  "   +  retcode);
   } 
   }   catch  (java.io.IOException iex)  ... {
    throw  iex;
  }   finally   ... {
    //  always release the connection after the request is done 
    method.releaseConnection();
    if  (data  !=   null )  ... {
     try   ... {
     data.close();
    }   catch  (Exception ex)  ... {

    } 
   } 
  } 
   return  result;
 } 
   /**/ /*  (non-Javadoc)
  * @see co.iproxy.http.ServiceInterface#syncRequest(java.lang.String)
   */ 
   public  String syncRequest(String request)  throws  IOException  ... {
   return   this .process(request);
 } 
 
   /**/ /*  (non-Javadoc)
  * @see co.iproxy.http.ServiceInterface#asyncRequest(java.lang.String)
   */ 
   public  String request(String request)  throws  IOException  ... {
   return   this .process(request);
 } 
}