Apache HttpClient - 中止请求

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  简述

  您可以使用 abort() 方法中止当前的 HTTP 请求，即，在调用此方法后，在特定请求上，它的执行将被中止。

  如果在一次执行后调用该方法，则该执行的响应不受影响，后续执行将被中止。
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  示例

  如果您观察以下示例，我们创建了一个 HttpGet 请求，使用 getMethod() 打印了使用的请求格式。

  然后，我们用相同的请求执行了另一次执行。再次使用 1^st 执行打印状态行。最后，打印第二次执行的状态行。

  如前所述，第 1^st 执行（在 abort 方法之前执行）的响应被打印（包括在 abort 方法之后写入的第二个状态行），并且所有后续执行的abort 方法后的当前请求调用异常失败。

  
  import org.apache.http.HttpResponse;
  import org.apache.http.client.methods.HttpGet;
  import org.apache.http.impl.client.CloseableHttpClient;
  import org.apache.http.impl.client.HttpClients;
  public class HttpGetExample {
     public static void main(String args[]) throws Exception{
     
        //Creating an HttpClient object
        CloseableHttpClient httpclient = HttpClients.createDefault();
        //Creating an HttpGet object
        HttpGet httpget = new HttpGet("http://www.jc2182.com/");
        //Printing the method used
        System.out.println(httpget.getMethod());
   
        //Executing the Get request
        HttpResponse httpresponse = httpclient.execute(httpget);
        //Printing the status line
        System.out.println(httpresponse.getStatusLine());
        httpget.abort();
        System.out.println(httpresponse.getEntity().getContentLength());
   
        //Executing the Get request
        HttpResponse httpresponse2 = httpclient.execute(httpget);
        System.out.println(httpresponse2.getStatusLine());
     }
  }
  

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  输出

  在执行时，上面的程序生成以下输出 -

  
  On executing, the above program generates the following output.
  GET
  HTTP/1.1 200 OK
  -1
  Exception in thread "main" org.apache.http.impl.execchain.RequestAbortedException:
  Request aborted
  at org.apache.http.impl.execchain.MainClientExec.execute(MainClientExec.java:180)
  at org.apache.http.impl.execchain.ProtocolExec.execute(ProtocolExec.java:185)
  at org.apache.http.impl.execchain.RetryExec.execute(RetryExec.java:89)
  at org.apache.http.impl.execchain.RedirectExec.execute(RedirectExec.java:110)
  at org.apache.http.impl.client.InternalHttpClient.doExecute(InternalHttpClient.java:185)
  at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:83)
  at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:108)
  at HttpGetExample.main(HttpGetExample.java:32)