[java] HttpRequest.execute () 사용 예외 : SingleClientConnManager의 잘못된 사용 : 연결이 여전히 할당 됨

유사한 예외 메시지 (적어도 Apache Jarkata Commons HTTP Client 4.2 이후)는 다음과 같습니다.

java.lang.IllegalStateException: Invalid use of BasicClientConnManager: connection still allocated.
Make sure to release the connection before allocating another one.

이 예외는 둘 이상의 스레드가 단일 org.apache.http.impl.client.DefaultHttpClient.

어떻게 당신은 4.2 만들 수 있습니다 DefaultHttpClient(인스턴스 스레드 스레드 두 개 이상의 스레드가 오류 메시지가 위받지 않고 상호 작용할 수 있다는 의미에서)을? 형식으로 DefaultHttpClient연결 풀링 ClientConnectionManager을 제공하십시오 org.apache.http.impl.conn.PoolingClientConnectionManager!

/* using
    <dependency>
        <groupId>org.apache.httpcomponents</groupId>
        <artifactId>httpclient</artifactId>
        <version>4.2.2</version>
    </dependency>
*/

import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.params.HttpConnectionParams;
import org.apache.http.client.HttpClient;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.impl.conn.PoolingClientConnectionManager;
import org.apache.http.impl.conn.SchemeRegistryFactory;
import org.apache.http.params.HttpParams;
import org.apache.http.client.methods.HttpGet;

public class MyComponent {

    private HttpClient client;

    {
        PoolingClientConnectionManager conMan = new PoolingClientConnectionManager( SchemeRegistryFactory.createDefault() );
        conMan.setMaxTotal(200);
        conMan.setDefaultMaxPerRoute(200);

        client = new DefaultHttpClient(conMan);

        //The following parameter configurations are not
        //neccessary for this example, but they show how
        //to further tweak the HttpClient
        HttpParams params = client.getParams();
        HttpConnectionParams.setConnectionTimeout(params, 20000);
        HttpConnectionParams.setSoTimeout(params, 15000);
    }


    //This method can be called concurrently by several threads
    private InputStream getResource(String uri) {
        try {
            HttpGet method = new HttpGet(uri);
            HttpResponse httpResponse = client.execute(method);
            int statusCode = httpResponse.getStatusLine().getStatusCode();
            InputStream is = null;
            if (HttpStatus.SC_OK == statusCode) {
                logger.debug("200 OK Amazon request");
                is = httpResponse.getEntity().getContent();
            } else {
                logger.debug("Something went wrong, statusCode is {}",
                        statusCode);
                 EntityUtils.consume(httpResponse.getEntity());
            }
            return is;
        } catch (Exception e) {
            logger.error("Something went terribly wrong", e);
            throw new RuntimeException(e);
        }
    }
}