Java tutorial
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For more * information on the Apache Software Foundation, please see * <http://www.apache.org/>. * */ package org.apache.http.impl.nio.client; import java.io.IOException; import org.apache.commons.logging.Log; import org.apache.http.ConnectionReuseStrategy; import org.apache.http.HttpException; import org.apache.http.HttpHost; import org.apache.http.HttpRequest; import org.apache.http.HttpResponse; import org.apache.http.client.config.RequestConfig; import org.apache.http.client.methods.Configurable; 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.concurrent.BasicFuture; import org.apache.http.conn.ConnectionKeepAliveStrategy; import org.apache.http.conn.routing.HttpRoute; import org.apache.http.nio.ContentDecoder; import org.apache.http.nio.ContentEncoder; import org.apache.http.nio.IOControl; import org.apache.http.nio.NHttpClientConnection; import org.apache.http.nio.conn.NHttpClientConnectionManager; import org.apache.http.nio.protocol.HttpAsyncRequestProducer; import org.apache.http.nio.protocol.HttpAsyncResponseConsumer; import org.apache.http.protocol.HttpCoreContext; import org.apache.http.protocol.HttpProcessor; /** * Default implementation of {@link org.apache.http.nio.protocol.HttpAsyncClientExchangeHandler}. * <p> * Instances of this class are expected to be accessed by one thread at a time only. * The {@link #cancel()} method can be called concurrently by multiple threads. */ class MinimalClientExchangeHandlerImpl<T> extends AbstractClientExchangeHandler { private final HttpAsyncRequestProducer requestProducer; private final HttpAsyncResponseConsumer<T> responseConsumer; private final HttpClientContext localContext; private final BasicFuture<T> resultFuture; private final HttpProcessor httpProcessor; public MinimalClientExchangeHandlerImpl(final Log log, final HttpAsyncRequestProducer requestProducer, final HttpAsyncResponseConsumer<T> responseConsumer, final HttpClientContext localContext, final BasicFuture<T> resultFuture, final NHttpClientConnectionManager connmgr, final HttpProcessor httpProcessor, final ConnectionReuseStrategy connReuseStrategy, final ConnectionKeepAliveStrategy keepaliveStrategy) { super(log, localContext, resultFuture, connmgr, connReuseStrategy, keepaliveStrategy); this.requestProducer = requestProducer; this.responseConsumer = responseConsumer; this.localContext = localContext; this.resultFuture = resultFuture; this.httpProcessor = httpProcessor; } @Override void releaseResources() { try { this.requestProducer.close(); } catch (final IOException ex) { this.log.debug("I/O error closing request producer", ex); } try { this.responseConsumer.close(); } catch (final IOException ex) { this.log.debug("I/O error closing response consumer", ex); } } @Override void executionFailed(final Exception ex) { this.requestProducer.failed(ex); this.responseConsumer.failed(ex); } @Override boolean executionCancelled() { final boolean cancelled = this.responseConsumer.cancel(); final T result = this.responseConsumer.getResult(); final Exception ex = this.responseConsumer.getException(); if (ex != null) { this.resultFuture.failed(ex); } else if (result != null) { this.resultFuture.completed(result); } else { this.resultFuture.cancel(); } return cancelled; } public void start() throws HttpException, IOException { final HttpHost target = this.requestProducer.getTarget(); final HttpRequest original = this.requestProducer.generateRequest(); if (original instanceof HttpExecutionAware) { ((HttpExecutionAware) original).setCancellable(this); } if (this.log.isDebugEnabled()) { this.log.debug("[exchange: " + getId() + "] start execution"); } if (original instanceof Configurable) { final RequestConfig config = ((Configurable) original).getConfig(); if (config != null) { this.localContext.setRequestConfig(config); } } final HttpRequestWrapper request = HttpRequestWrapper.wrap(original); final HttpRoute route = new HttpRoute(target); setCurrentRequest(request); setRoute(route); this.localContext.setAttribute(HttpCoreContext.HTTP_REQUEST, request); this.localContext.setAttribute(HttpCoreContext.HTTP_TARGET_HOST, target); this.localContext.setAttribute(HttpClientContext.HTTP_ROUTE, route); this.httpProcessor.process(request, this.localContext); requestConnection(); } @Override public HttpRequest generateRequest() throws IOException, HttpException { verifytRoute(); if (!isRouteEstablished()) { onRouteToTarget(); onRouteComplete(); } final NHttpClientConnection localConn = getConnection(); this.localContext.setAttribute(HttpCoreContext.HTTP_CONNECTION, localConn); final RequestConfig config = this.localContext.getRequestConfig(); if (config.getSocketTimeout() > 0) { localConn.setSocketTimeout(config.getSocketTimeout()); } return getCurrentRequest(); } @Override public void produceContent(final ContentEncoder encoder, final IOControl ioctrl) throws IOException { if (this.log.isDebugEnabled()) { this.log.debug("[exchange: " + getId() + "] produce content"); } this.requestProducer.produceContent(encoder, ioctrl); if (encoder.isCompleted()) { this.requestProducer.resetRequest(); } } @Override public void requestCompleted() { if (this.log.isDebugEnabled()) { this.log.debug("[exchange: " + getId() + "] Request completed"); } this.requestProducer.requestCompleted(this.localContext); } @Override public void responseReceived(final HttpResponse response) throws IOException, HttpException { if (this.log.isDebugEnabled()) { this.log.debug("[exchange: " + getId() + "] Response received " + response.getStatusLine()); } this.localContext.setAttribute(HttpCoreContext.HTTP_RESPONSE, response); this.httpProcessor.process(response, this.localContext); setCurrentResponse(response); this.responseConsumer.responseReceived(response); } @Override public void consumeContent(final ContentDecoder decoder, final IOControl ioctrl) throws IOException { if (this.log.isDebugEnabled()) { this.log.debug("[exchange: " + getId() + "] Consume content"); } this.responseConsumer.consumeContent(decoder, ioctrl); if (!decoder.isCompleted() && this.responseConsumer.isDone()) { markConnectionNonReusable(); try { markCompleted(); releaseConnection(); this.resultFuture.cancel(); } finally { close(); } } } @Override public void responseCompleted() throws IOException, HttpException { manageConnectionPersistence(); this.responseConsumer.responseCompleted(this.localContext); if (this.log.isDebugEnabled()) { this.log.debug("[exchange: " + getId() + "] Response processed"); } try { markCompleted(); releaseConnection(); final T result = this.responseConsumer.getResult(); final Exception ex = this.responseConsumer.getException(); if (ex == null) { this.resultFuture.completed(result); } else { this.resultFuture.failed(ex); } } finally { close(); } } @Override public void inputTerminated() { close(); } public void abortConnection() { discardConnection(); } }