/*
* ====================================================================
* 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/>.
*
*/
package org.apache.http.impl.nio.client;
import java.io.IOException;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicReference;
import org.apache.commons.logging.Log;
import org.apache.http.ConnectionClosedException;
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.HttpExecutionAware;
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.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;
/**
* Default implementation of {@link 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 DefaultClientExchangeHandlerImpl<T>
implements HttpAsyncClientExchangeHandler, InternalConnManager, Cancellable {
private final Log log;
private final HttpAsyncRequestProducer requestProducer;
private final HttpAsyncResponseConsumer<T> responseConsumer;
private final HttpClientContext localContext;
private final BasicFuture<T> resultFuture;
private final NHttpClientConnectionManager connmgr;
private final InternalClientExec exec;
private final InternalState state;
private final AtomicReference<NHttpClientConnection> managedConn;
private final AtomicBoolean closed;
private final AtomicBoolean completed;
public DefaultClientExchangeHandlerImpl(
final Log log,
final HttpAsyncRequestProducer requestProducer,
final HttpAsyncResponseConsumer<T> responseConsumer,
final HttpClientContext localContext,
final BasicFuture<T> resultFuture,
final NHttpClientConnectionManager connmgr,
final InternalClientExec exec) {
super();
this.log = log;
this.requestProducer = requestProducer;
this.responseConsumer = responseConsumer;
this.localContext = localContext;
this.resultFuture = resultFuture;
this.connmgr = connmgr;
this.exec = exec;
this.state = new InternalState(requestProducer, responseConsumer, localContext);
this.closed = new AtomicBoolean(false);
this.completed = new AtomicBoolean(false);
this.managedConn = new AtomicReference<NHttpClientConnection>(null);
}
public void close() {
if (this.closed.getAndSet(true)) {
return;
}
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 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);
}
this.exec.prepare(this.state, target, original);
requestConnection();
}
public boolean isDone() {
return this.completed.get();
}
public HttpRequest generateRequest() throws IOException, HttpException {
return this.exec.generateRequest(this.state, this);
}
public void produceContent(
final ContentEncoder encoder, final IOControl ioctrl) throws IOException {
this.exec.produceContent(this.state, encoder, ioctrl);
}
public void requestCompleted() {
this.exec.requestCompleted(this.state);
}
public void responseReceived(
final HttpResponse response) throws IOException, HttpException {
this.exec.responseReceived(this.state, response);
}
public void consumeContent(
final ContentDecoder decoder, final IOControl ioctrl) throws IOException {
this.exec.consumeContent(this.state, decoder, ioctrl);
if (!decoder.isCompleted() && this.responseConsumer.isDone()) {
if (this.completed.compareAndSet(false, true)) {
this.resultFuture.cancel();
}
this.state.setNonReusable();
releaseConnection();
}
}
public void responseCompleted() throws IOException, HttpException {
this.exec.responseCompleted(this.state, this);
if (this.state.getFinalResponse() != null || this.resultFuture.isDone()) {
try {
this.completed.set(true);
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();
}
} else {
NHttpClientConnection localConn = this.managedConn.get();
if (localConn != null && !localConn.isOpen()) {
releaseConnection();
localConn = null;
}
if (localConn != null) {
localConn.requestOutput();
} else {
requestConnection();
}
}
}
public void inputTerminated() {
if (!this.completed.get()) {
requestConnection();
} else {
close();
}
}
public void releaseConnection() {
final NHttpClientConnection localConn = this.managedConn.getAndSet(null);
if (localConn != null) {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.state.getId() + "] releasing connection");
}
localConn.getContext().removeAttribute(HttpAsyncRequestExecutor.HTTP_HANDLER);
if (this.state.isReusable()) {
this.connmgr.releaseConnection(localConn,
this.localContext.getUserToken(),
this.state.getValidDuration(), TimeUnit.MILLISECONDS);
} else {
try {
localConn.close();
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.state.getId() + "] connection discarded");
}
} catch (final IOException ex) {
if (this.log.isDebugEnabled()) {
this.log.debug(ex.getMessage(), ex);
}
} finally {
this.connmgr.releaseConnection(localConn, null, 0, TimeUnit.MILLISECONDS);
}
}
}
}
public void abortConnection() {
discardConnection();
}
private void discardConnection() {
final NHttpClientConnection localConn = this.managedConn.getAndSet(null);
if (localConn != null) {
try {
localConn.shutdown();
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.state.getId() + "] connection aborted");
}
} catch (final IOException ex) {
if (this.log.isDebugEnabled()) {
this.log.debug(ex.getMessage(), ex);
}
} finally {
this.connmgr.releaseConnection(localConn, null, 0, TimeUnit.MILLISECONDS);
}
}
}
public void failed(final Exception ex) {
try {
this.requestProducer.failed(ex);
this.responseConsumer.failed(ex);
} finally {
try {
this.resultFuture.failed(ex);
} finally {
close();
}
}
}
public boolean cancel() {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.state.getId() + "] 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 void connectionAllocated(final NHttpClientConnection managedConn) {
try {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.state.getId() + "] Connection allocated: " + managedConn);
}
this.managedConn.set(managedConn);
if (this.closed.get()) {
releaseConnection();
return;
}
managedConn.getContext().setAttribute(HttpAsyncRequestExecutor.HTTP_HANDLER, this);
managedConn.requestOutput();
if (!managedConn.isOpen()) {
failed(new ConnectionClosedException("Connection closed"));
}
} catch (final RuntimeException runex) {
failed(runex);
throw runex;
}
}
private void connectionRequestFailed(final Exception ex) {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.state.getId() + "] connection request failed");
}
try {
this.resultFuture.failed(ex);
} finally {
close();
}
}
private void connectionRequestCancelled() {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.state.getId() + "] Connection request cancelled");
}
try {
this.resultFuture.cancel();
} finally {
close();
}
}
private void requestConnection() {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.state.getId() + "] Request connection for " +
this.state.getRoute());
}
discardConnection();
this.state.setValidDuration(0);
this.state.setNonReusable();
this.state.setRouteEstablished(false);
this.state.setRouteTracker(null);
final HttpRoute route = this.state.getRoute();
final Object userToken = this.localContext.getUserToken();
final RequestConfig config = this.localContext.getRequestConfig();
this.connmgr.requestConnection(
route,
userToken,
config.getConnectTimeout(),
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();
}
});
}
public NHttpClientConnection getConnection() {
return this.managedConn.get();
}
}