HttpClient doPost doGet 请求 返回内存流

 

import java.io.ByteArrayOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.ObjectOutputStream;

import java.io.OutputStream;

import java.io.UnsupportedEncodingException;

import java.util.ArrayList;

import java.util.List;

import java.util.Map;

import org.apache.http.HttpEntity;

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.HttpGet;

import org.apache.http.client.methods.HttpPost;

import org.apache.http.entity.ContentProducer;

import org.apache.http.entity.EntityTemplate;

import org.apache.http.impl.client.DefaultHttpClient;

import org.apache.http.message.BasicNameValuePair;

import org.apache.http.util.EntityUtils;

/**

 * http invoker for doPost request or doGet request, return memory stream

 * <code>OutputStream</code>,ie. <code>ByteArrayOutputStream</code>

 * 

 * 

 * @author 

 * @see org.apache.http.client.HttpClient

 */

public class HttpInvoker

{

/**

* doGet方式访问URL

* 

* @param url

* @return OutputStream

*/

public static OutputStream doGet(String url)

{

HttpClient httpclient = new DefaultHttpClient();

OutputStream os = null;

try

{

HttpGet httpget = new HttpGet(url);

HttpResponse response = httpclient.execute(httpget);

HttpEntity entity = response.getEntity();

if (entity != null)

{

InputStream instream = entity.getContent();

os = new ByteArrayOutputStream();

int temp = 0;

while ((temp = instream.read()) != -1)

{

os.write(temp);

}

os.flush();

os.close();

return os;

}

}

catch (Exception e)

{

}

finally

{

httpclient.getConnectionManager().shutdown();

}

return null;

}

/**

* http url request with parameter map

* 

* @param url server url

* @param parameterMap Parameters

* @return OutputStream

*/

public static OutputStream doPostWithUrlParams(String url,

Map<String , Object> parameterMap)

{

List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();

for (Map.Entry<String , Object> element : parameterMap.entrySet())

{

nameValuePairs.add(new BasicNameValuePair(element.getKey(), String

.valueOf(element.getValue())));

}

try

{

return doPost(url, new UrlEncodedFormEntity(nameValuePairs));

}

catch (UnsupportedEncodingException e)

{

}

return null;

}

/**

* post方式写对象流到服务端

* 

* @param url server url

* @param obj Object

* @return OutputStream

*/

public static OutputStream doPostWithObject(String url, final Object obj)

{

ContentProducer cp = new ContentProducer()

{

// 二进制流

public void writeTo(OutputStream outstream) throws IOException

{

ObjectOutputStream oos = new ObjectOutputStream(outstream);

oos.writeObject(obj);

oos.flush();

oos.close();

}

};

return doPost(url, new EntityTemplate(cp));

}

/**

* 

* httpClient 执行post请求 返回 OutputStream对象

* 

* @param url String

* @param entity HttpEntity

* @return OutputStream

*/

private static OutputStream doPost(String url, HttpEntity entity)

{

HttpClient client = new DefaultHttpClient();

HttpPost post = new HttpPost(url);

OutputStream os = null;

post.setEntity(entity);

try

{

HttpResponse response = client.execute(post);

HttpEntity resEntity = response.getEntity();

InputStream in = resEntity.getContent();

if (resEntity != null)

{

os = new ByteArrayOutputStream();

int temp = 0;

while ((temp = in.read()) != -1)

{

os.write(temp);

}

os.flush();

os.close();

EntityUtils.consume(resEntity);

return os;

}

}

catch (Exception e)

{

}

finally

{

client.getConnectionManager().shutdown();

}

return null;

}

}