用单例模式为应用中所有HTTP请求服务创建一个HttpClient

import org.apache.http.HttpVersion;
 
 
 

  import org.apache.http.client.HttpClient;
 
 
 

  import org.apache.http.conn.ClientConnectionManager;
 
 
 

  import org.apache.http.conn.params.ConnManagerParams;
 
 
 

  import org.apache.http.conn.scheme.PlainSocketFactory;
 
 
 

  import org.apache.http.conn.scheme.Scheme;
 
 
 

  import org.apache.http.conn.scheme.SchemeRegistry;
 
 
 

  import org.apache.http.conn.ssl.SSLSocketFactory;
 
 
 

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

  import org.apache.http.impl.conn.tsccm.ThreadSafeClientConnManager;
 
 
 

  import org.apache.http.params.BasicHttpParams;
 
 
 

  import org.apache.http.params.HttpConnectionParams;
 
 
 

  import org.apache.http.params.HttpParams;
 
 
 

  import org.apache.http.params.HttpProtocolParams;
 
 
 

  import org.apache.http.protocol.HTTP;
 
 
 

   
 
 
 

  public class CustomHttpClient {
 
 
 

  private static HttpClient customHttpClient;
 
 
 

   
 
 
 

  private CustomHttpClient(){};
 
 
 

   
 
 
 

  public static synchronized HttpClient getHttpClient(){
 
 
 

  if(customHttpClient == null){
 
 
 

  HttpParams params = new BasicHttpParams();
 
 
 

  HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
 
 
 

  HttpProtocolParams.setContentCharset(params, HTTP.DEFAULT_CONTENT_CHARSET);
 
 
 

  HttpProtocolParams.setUseExpectContinue(params, true);
 
 
 

  HttpProtocolParams.setUserAgent(params,  "Mozilla/5.0(Linux;U;Android 2.2.1;en-us;Nexus One Build.FRG83) "
 
 
 

                      + "AppleWebKit/553.1(KHTML,like Gecko) Version/4.0 Mobile Safari/533.1");
 
 
 

  /* 从连接池中取连接的超时时间 */
 
 
 

  ConnManagerParams.setTimeout(params, 1000);
 
 
 

  /* 连接超时 */
 
 
 

  HttpConnectionParams.setConnectionTimeout(params, 5000);
 
 
 

  /* 请求超时 */
 
 
 

  HttpConnectionParams.setSoTimeout(params, 10000);
 
 
 

  // 设置我们的HttpClient支持HTTP和HTTPS两种模式
 
 
 

              SchemeRegistry schReg = new SchemeRegistry();
 
 
 

              schReg.register(new Scheme("http", PlainSocketFactory
 
 
 

                      .getSocketFactory(), 80));
 
 
 

              schReg.register(new Scheme("https", SSLSocketFactory
 
 
 

                      .getSocketFactory(), 443));
 
 
 

           // 使用线程安全的连接管理来创建HttpClient
 
 
 

              ClientConnectionManager conMgr = new ThreadSafeClientConnManager(
 
 
 

                      params, schReg);
 
 
 

              customHttpClient = new DefaultHttpClient(conMgr, params);
 
 
 

  }
 
 
 

  return customHttpClient;
 
 
 

  }
 
 
 

  public Object clone() throws CloneNotSupportedException{
 
 
 

  throw new CloneNotSupportedException();
 
 
 

  }
 
 
 

  }