Http客户端错误：目标服务器无法响应

java apache httpclient connection-pooling

2022-09-02 04:10:47

我正在尝试使用 HTTP 客户端使用设置单个主机的最大连接数来命中服务器PoolingClientConnectionManager

//Code that initializes my connection manager and HTTP client 
HttpParams httpParam = httpclient.getParams();
HttpConnectionParams.setSoTimeout(httpParam, SOCKET_TIMEOUT);

HttpConnectionParams.setConnectionTimeout(httpParam, CONN_TIMEOUT);

httpclient.setParams(httpParam);

//Run a thread which closes Expired connections
new ConnectionManager(connManager).start(); 

//Code that executes my request 
HttpPost httpPost = new HttpPost(url);
        HttpEntity httpEntity = new StringEntity(request, "UTF-8");
httpPost.setEntity(httpEntity);

Header acceptEncoding = new BasicHeader("Accept-Encoding", "gzip,deflate");
httpPost.setHeader(acceptEncoding);     

if(contenttype != null && !contenttype.equals("")){
    Header contentType = new BasicHeader("Content-Type", contenttype);
    httpPost.setHeader(contentType);
}
InputStream inputStream = null;
LOG.info(dataSource + URL + url + REQUEST + request);

HttpResponse response = httpclient.execute(httpPost);

也就是说，我们正在使用连接池来实现http持久性。

我们偶尔会得到这个错误：

The target server failed to respond
org.apache.http.NoHttpResponseException: The target server failed to respond
        at org.apache.http.impl.conn.DefaultHttpResponseParser.parseHead(DefaultHttpResponseParser.java:95)
        at org.apache.http.impl.conn.DefaultHttpResponseParser.parseHead(DefaultHttpResponseParser.java:62)
        at org.apache.http.impl.io.AbstractMessageParser.parse(AbstractMessageParser.java:254)
        at org.apache.http.impl.AbstractHttpClientConnection.receiveResponseHeader(AbstractHttpClientConnection.java:289)
        at org.apache.http.impl.conn.DefaultClientConnection.receiveResponseHeader(DefaultClientConnection.java:252)
        at org.apache.http.impl.conn.ManagedClientConnectionImpl.receiveResponseHeader(ManagedClientConnectionImpl.java:191)
        at org.apache.http.protocol.HttpRequestExecutor.doReceiveResponse(HttpRequestExecutor.java:300)
        at org.apache.http.protocol.HttpRequestExecutor.execute(HttpRequestExecutor.java:127)
        at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:517)
        at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:906)

有没有人知道如何解决这个问题？

我们也在关闭空闲连接。

可以一些请帮忙。

http://hc.apache.org/httpcomponents-client-ga/tutorial/html/connmgmt.html

答案 1

可能，这是HttpClient中的一个错误。

如果您使用的是 HttpClient 4.4，请尝试升级到 4.4.1。

如果您想了解更多信息，请查看此链接。

如果无法升级，以下链接可能会有所帮助。

http://www.nuxeo.com/blog/using-httpclient-properly-avoid-closewait-tcp-connections/

祝你好运！

答案 2

最近在使用时遇到类似情况。HttpClient 5

启用日志时，发现问题是由过时的连接引起的。HttpClient

添加以下内容有助于解决问题，它可以检测并验证在重用之前在池中保持非活动状态时已过时的连接。

PoolingHttpClientConnectionManager connectionManager = new PoolingHttpClientConnectionManager();

connectionManager.setValidateAfterInactivity(timeinmilliseconds);