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package org.apache.http.impl.execchain;

import java.io.IOException;
import java.io.InterruptedIOException;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.http.Header;
import org.apache.http.HttpException;
import org.apache.http.annotation.Contract;
import org.apache.http.annotation.ThreadingBehavior;
import org.apache.http.client.ServiceUnavailableRetryStrategy;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpExecutionAware;
import org.apache.http.client.methods.HttpRequestWrapper;
import org.apache.http.client.protocol.HttpClientContext;
import org.apache.http.conn.routing.HttpRoute;
import org.apache.http.util.Args;

Request executor in the request execution chain that is responsible for making a decision whether a request that received a non-2xx response from the target server should be re-executed.

Further responsibilities such as communication with the opposite endpoint is delegated to the next executor in the request execution chain.

Since:4.3
/** * Request executor in the request execution chain that is responsible * for making a decision whether a request that received a non-2xx response * from the target server should be re-executed. * <p> * Further responsibilities such as communication with the opposite * endpoint is delegated to the next executor in the request execution * chain. * </p> * * @since 4.3 */
@Contract(threading = ThreadingBehavior.IMMUTABLE_CONDITIONAL) public class ServiceUnavailableRetryExec implements ClientExecChain { private final Log log = LogFactory.getLog(getClass()); private final ClientExecChain requestExecutor; private final ServiceUnavailableRetryStrategy retryStrategy; public ServiceUnavailableRetryExec( final ClientExecChain requestExecutor, final ServiceUnavailableRetryStrategy retryStrategy) { super(); Args.notNull(requestExecutor, "HTTP request executor"); Args.notNull(retryStrategy, "Retry strategy"); this.requestExecutor = requestExecutor; this.retryStrategy = retryStrategy; } @Override public CloseableHttpResponse execute( final HttpRoute route, final HttpRequestWrapper request, final HttpClientContext context, final HttpExecutionAware execAware) throws IOException, HttpException { final Header[] origheaders = request.getAllHeaders(); for (int c = 1;; c++) { final CloseableHttpResponse response = this.requestExecutor.execute( route, request, context, execAware); try { if (this.retryStrategy.retryRequest(response, c, context) && RequestEntityProxy.isRepeatable(request)) { response.close(); final long nextInterval = this.retryStrategy.getRetryInterval(); if (nextInterval > 0) { try { this.log.trace("Wait for " + nextInterval); Thread.sleep(nextInterval); } catch (final InterruptedException e) { Thread.currentThread().interrupt(); throw new InterruptedIOException(); } } request.setHeaders(origheaders); } else { return response; } } catch (final RuntimeException ex) { response.close(); throw ex; } } } }