Http Client 4.5 没有在 Java 中使用池连接管理器重用相同的连接

Question

我下面的代码使用的是 apache http 客户端 4.5 版本的池连接管理器。如果我发出 50 个请求，我会在 netstat 中看到正在使用 50 个不同的 tcp 端口，但最多可随时使用 5 个连接。我在wireshark中看到也有过滤tcp.flags.syn==1 && tcp.flags.ack==0器，它在过滤器中创建50个数据包，所以它使用不同的连接而不是使用相同的连接，那么为什么不能呢？

我的代码：

import javax.net.ssl.SSLContext;

import org.apache.http.HttpEntity;
import org.apache.http.HttpHost;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.config.Registry;
import org.apache.http.config.RegistryBuilder;
import org.apache.http.conn.routing.HttpRoute;
import org.apache.http.conn.socket.ConnectionSocketFactory;
import org.apache.http.conn.socket.PlainConnectionSocketFactory;
import org.apache.http.conn.ssl.NoopHostnameVerifier;
import org.apache.http.conn.ssl.SSLConnectionSocketFactory;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;
import org.apache.http.util.EntityUtils;
import org.glassfish.jersey.SslConfigurator;
import org.json.JSONException;
import org.json.JSONObject;

public class App3Conn {
    private static CloseableHttpClient client;


    static String target="https://example.com";

    static PoolingHttpClientConnectionManager cm ;
static{

SslConfigurator sslConfig = SslConfigurator.newInstance()
            .securityProtocol("TLS")
            .keyStoreFile("/Users/file")
            .keyStorePassword("passw")
            .keyStoreType("JKS")
            .trustStoreFile("/Users/file");

    SSLContext sslCtx = sslConfig.createSSLContext();
    SSLConnectionSocketFactory sslsf = new SSLConnectionSocketFactory(sslCtx,NoopHostnameVerifier.INSTANCE);
    Registry<ConnectionSocketFactory> r = RegistryBuilder.<ConnectionSocketFactory>create()
            .register("http", PlainConnectionSocketFactory.getSocketFactory())
            .register("https", sslsf)
            .build();


    cm = new PoolingHttpClientConnectionManager(r);
    cm.setMaxTotal(15);
    cm.setDefaultMaxPerRoute(5);

    client = HttpClients.custom().setSSLSocketFactory(sslsf).setConnectionManager(cm).build();


}
public static void main(String a[]) throws JSONException, ClientProtocolException, IOException
{

    JSONObject jsonMessage = new JSONObject();



    JSONObject jsonResponse;

    jsonMessage.put("keyID", "keyID" );


     StringEntity se = new StringEntity(jsonMessage.toString());
     CloseableHttpResponse response2;
    HttpPost httpPost = new HttpPost(target);
    httpPost.setEntity(se);
    httpPost.setHeader("Accept", "application/json");
    httpPost.setHeader("Content-type", "application/json");
    httpPost.setHeader("Connection", "keep-alive");
    int i;
    for(i=0;i<50;i++)
    {

        response2 = client.execute(httpPost);


     HttpEntity entity2 = response2.getEntity();
     String result = EntityUtils.toString(entity2);

     EntityUtils.consume(entity2);


     jsonResponse = new JSONObject(result);

    String text = jsonResponse.getString("result");


    response2.close();
    }
}
}

Answer 1

我以前见过这个。这取决于 Apache 连接池的工作方式。不透明state成员与池条目相关联，并且在请求（租用）池条目时必须与请求的状态匹配。

当进行连接租用尝试时，state请求的是null。但是，当连接放回池中时，该连接将state设置为X500PrincipalSSL 对等方的对象。这发生在DefaultUserTokenHandler课堂上。幸运的是，当我们创建HttpClient类时，这是可以覆盖的。下面是一个例子：

HttpClient apacheHttpClient = HttpClients.custom()
    .setConnectionReuseStrategy(new DefaultConnectionReuseStrategy())
    .setConnectionManager(new PoolingHttpClientConnectionManager(r))
    .setUserTokenHandler(new UserTokenHandler() {
      @Override
      public Object getUserToken(HttpContext context) {
        return null;
      }
    })
    .build();

DefaultUserTokenHandler如果HttpClient您创建的可以通过相同的 HTTP 路由连接到多个 SSL 对等点，请检查您是否丢失了您依赖的任何内容，并且不要使用此方法。在我的情况下，此客户端用于连接到单个 SSL 服务器。