/*
* ====================================================================
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
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*/
package org.apache.http.impl.nio.client;
import java.io.IOException;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicLong;
import org.apache.commons.logging.Log;
import org.apache.http.ConnectionClosedException;
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.concurrent.Cancellable;
import org.apache.http.concurrent.FutureCallback;
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.HttpAsyncClientExchangeHandler;
import org.apache.http.nio.protocol.HttpAsyncRequestExecutor;
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;
public class MinimalClientExchangeHandlerImpl<T>
implements HttpAsyncClientExchangeHandler, Cancellable {
private static final AtomicLong COUNTER = new AtomicLong(1);
private final Log log;
private final long id;
private final HttpAsyncRequestProducer requestProducer;
private final HttpAsyncResponseConsumer<T> responseConsumer;
private final HttpClientContext localContext;
private final BasicFuture<T> resultFuture;
private final NHttpClientConnectionManager connmgr;
private final HttpProcessor httpProcessor;
private final ConnectionReuseStrategy connReuseStrategy;
private final ConnectionKeepAliveStrategy keepaliveStrategy;
private volatile boolean closed;
private volatile boolean completed;
private HttpRoute route;
private NHttpClientConnection managedConn;
private HttpRequestWrapper request;
private HttpResponse response;
private boolean reusable;
private long validDuration;
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();
this.log = log;
this.id = COUNTER.getAndIncrement();
this.requestProducer = requestProducer;
this.responseConsumer = responseConsumer;
this.localContext = localContext;
this.resultFuture = resultFuture;
this.connmgr = connmgr;
this.httpProcessor = httpProcessor;
this.connReuseStrategy = connReuseStrategy;
this.keepaliveStrategy = keepaliveStrategy;
}
public synchronized void close() {
if (this.closed) {
return;
}
this.closed = true;
abortConnection();
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);
}
}
public synchronized void start() throws HttpException, IOException {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] Start execution");
}
final HttpHost target = this.requestProducer.getTarget();
final HttpRequest original = this.requestProducer.generateRequest();
if (original instanceof HttpExecutionAware) {
((HttpExecutionAware) original).setCancellable(this);
}
if (original instanceof Configurable) {
final RequestConfig config = ((Configurable) original).getConfig();
if (config != null) {
this.localContext.setRequestConfig(config);
}
}
this.request = HttpRequestWrapper.wrap(original);
this.route = new HttpRoute(target);
this.localContext.setAttribute(HttpClientContext.HTTP_REQUEST, this.request);
this.localContext.setAttribute(HttpClientContext.HTTP_TARGET_HOST, target);
this.localContext.setAttribute(HttpClientContext.HTTP_ROUTE, this.route);
this.httpProcessor.process(this.request, this.localContext);
requestConnection();
}
public boolean isDone() {
return this.completed;
}
public synchronized HttpRequest generateRequest() throws IOException, HttpException {
if (!this.connmgr.isRouteComplete(this.managedConn)) {
this.connmgr.initialize(this.managedConn, this.route, this.localContext);
this.connmgr.routeComplete(this.managedConn, this.route, this.localContext);
}
return this.request;
}
public synchronized void produceContent(
final ContentEncoder encoder, final IOControl ioctrl) throws IOException {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] Produce content");
}
this.requestProducer.produceContent(encoder, ioctrl);
if (encoder.isCompleted()) {
this.requestProducer.resetRequest();
}
}
public synchronized void requestCompleted() {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] Request completed");
}
this.requestProducer.requestCompleted(this.localContext);
}
public synchronized void responseReceived(
final HttpResponse response) throws IOException, HttpException {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] Response received " + response.getStatusLine());
}
this.localContext.setAttribute(HttpClientContext.HTTP_RESPONSE, response);
this.httpProcessor.process(response, this.localContext);
this.responseConsumer.responseReceived(response);
this.response = response;
}
public synchronized void consumeContent(
final ContentDecoder decoder, final IOControl ioctrl) throws IOException {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] Consume content");
}
this.responseConsumer.consumeContent(decoder, ioctrl);
}
public synchronized void responseCompleted() throws IOException, HttpException {
if (this.resultFuture.isDone()) {
this.completed = true;
releaseConnection();
return;
}
if (this.connReuseStrategy.keepAlive(this.response, this.localContext)) {
this.validDuration = this.keepaliveStrategy.getKeepAliveDuration(this.response,
this.localContext);
if (this.log.isDebugEnabled()) {
String s;
if (this.validDuration > 0) {
s = "for " + this.validDuration + " " + TimeUnit.MILLISECONDS;
} else {
s = "indefinitely";
}
this.log.debug("[exchange: " + this.id + "] Connection can be kept alive " + s);
}
this.reusable = true;
} else {
this.validDuration = 0;
this.reusable = false;
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] Connection cannot be kept alive");
}
}
this.responseConsumer.responseCompleted(this.localContext);
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] Response processed");
}
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);
}
this.completed = true;
}
public void inputTerminated() {
close();
}
public synchronized void failed(final Exception ex) {
try {
this.requestProducer.failed(ex);
this.responseConsumer.failed(ex);
} finally {
try {
this.resultFuture.failed(ex);
} finally {
close();
}
}
}
public synchronized boolean cancel() {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] Cancelled");
}
try {
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;
} catch (final RuntimeException runex) {
this.resultFuture.failed(runex);
throw runex;
} finally {
close();
}
}
private synchronized void connectionAllocated(final NHttpClientConnection managedConn) {
try {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] Connection allocated: " + managedConn);
}
this.managedConn = managedConn;
if (this.closed) {
releaseConnection();
return;
}
this.localContext.setAttribute(HttpCoreContext.HTTP_CONNECTION, managedConn);
if (!managedConn.isOpen()) {
failed(new ConnectionClosedException("Connection closed"));
} else {
this.managedConn.getContext().setAttribute(HttpAsyncRequestExecutor.HTTP_HANDLER, this);
this.managedConn.requestOutput();
}
} catch (final RuntimeException runex) {
failed(runex);
throw runex;
}
}
private synchronized void connectionRequestFailed(final Exception ex) {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] Connection request failed");
}
try {
this.resultFuture.failed(ex);
} finally {
close();
}
}
private synchronized void connectionRequestCancelled() {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] Connection request cancelled");
}
try {
this.resultFuture.cancel();
} finally {
close();
}
}
private void requestConnection() {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] Request connection for " + this.route);
}
final Object userToken = this.localContext.getUserToken();
final RequestConfig config = this.localContext.getRequestConfig();
this.connmgr.requestConnection(
this.route,
userToken,
config.getConnectionRequestTimeout(), TimeUnit.MILLISECONDS,
new FutureCallback<NHttpClientConnection>() {
public void completed(final NHttpClientConnection managedConn) {
connectionAllocated(managedConn);
}
public void failed(final Exception ex) {
connectionRequestFailed(ex);
}
public void cancelled() {
connectionRequestCancelled();
}
});
}
private void releaseConnection() {
if (this.managedConn != null) {
try {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] Releasing connection");
}
this.managedConn.getContext().removeAttribute(HttpAsyncRequestExecutor.HTTP_HANDLER);
if (this.reusable) {
this.connmgr.releaseConnection(this.managedConn,
this.localContext.getUserToken(),
this.validDuration, TimeUnit.MILLISECONDS);
this.managedConn = null;
}
} finally {
abortConnection();
}
}
}
private void abortConnection() {
if (this.managedConn != null) {
try {
this.managedConn.shutdown();
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] Connection discarded");
}
} catch (final IOException ex) {
if (this.log.isDebugEnabled()) {
this.log.debug(ex.getMessage(), ex);
}
} finally {
this.connmgr.releaseConnection(
this.managedConn, null, 0, TimeUnit.MILLISECONDS);
}
}
this.managedConn = null;
}
}