采用Jakarta的HttpClient API模拟客户端GET和POST提交

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%J***A_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://192.18.0.19:9080/care/careTest/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://12.20.69.50:5080/Web/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("192.18.254.22", 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://12.20.69.80:4080/Web/Servicelet;


String host = "12.21.6.81";


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("192.68.54.212", 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);


}


}