Apache HttpComponents HttpClient 超时

Question

如何在httpcomponents httpclient中设置连接超时？我在以下位置找到了文档： http://hc.apache。 org/httpcomponents-client-ga/tutorial/html/connmgmt.html 但尚不清楚这些参数的实际设置方式。

此外，解释 SO_TIMEOUT 和 CONNECTION_TIMEOUT 之间的差异也会有所帮助。

Answer 1

在 Apache Http Client 4.3 版本中，配置被重构（再次）。新的方式看起来像这样：

RequestConfig.Builder requestBuilder = RequestConfig.custom();
requestBuilder.setConnectTimeout(timeout);
requestBuilder.setConnectionRequestTimeout(timeout);

HttpClientBuilder builder = HttpClientBuilder.create();     
builder.setDefaultRequestConfig(requestBuilder.build());
HttpClient client = builder.build();

Answer 2

在 HttpClient 4.3 版本中，您可以使用下面的示例..假设 5 秒

int timeout = 5;
RequestConfig config = RequestConfig.custom()
  .setConnectTimeout(timeout * 1000)
  .setConnectionRequestTimeout(timeout * 1000)
  .setSocketTimeout(timeout * 1000).build();
CloseableHttpClient client = 
  HttpClientBuilder.create().setDefaultRequestConfig(config).build();
HttpGet request = new HttpGet("http://localhost:8080/service"); // GET Request
response = client.execute(request);

Answer 3

@jontro 的答案是正确的，但有一个关于如何执行此操作的代码片段总是很好。有两种方法可以执行此操作：

版本 1：为每个参数设置 10 秒超时：

HttpClient httpclient = new DefaultHttpClient();
// this one causes a timeout if a connection is established but there is 
// no response within 10 seconds
httpclient.getParams().setParameter(CoreConnectionPNames.SO_TIMEOUT, 10 * 1000);

// this one causes a timeout if no connection is established within 10 seconds
httpclient.getParams().setParameter(CoreConnectionPNames.CONNECTION_TIMEOUT, 10 * 1000);

// now do the execute:
HttpGet httpget = new HttpGet(URL);
HttpResponse response = httpclient.execute(httpget);

版本 2：还为以下每个参数设置 10 秒超时：

HttpParams params = new BasicHttpParams();
HttpConnectionParams.setConnectionTimeout(params, 10 * 1000);
HttpConnectionParams.setSoTimeout(params, 10 * 1000);

HttpClient httpclient = new DefaultHttpClient(params);
HttpGet httpget = new HttpGet(URL);
HttpResponse response = httpclient.execute(httpget);

Answer 4

在第 2.5 节中，您会看到一个示例，说明如何设置 CONNECTION_TIMEOUT 参数。

CONNECTION_TIMEOUT 是等待初始连接的时间，SO_TIMEOUT 是连接建立后读取数据包时等待的超时时间。

Answer 5

我为整个请求设置了硬超时，以解决 java.net.SocketInputStream.socketRead0 问题。

private static final ScheduledExecutorService SCHEDULED_EXECUTOR = Executors.newSingleThreadScheduledExecutor()

HttpGet request = new HttpGet("http://www.example.com")
final Runnable delayedTask = new Runnable() {
    @Override
    public void run() {
        request.abort()
    }
}
SCHEDULED_EXECUTOR.schedule(delayedTask, 100000, TimeUnit.MILLISECONDS)