org.apache.http.impl.nio.client.AbstractClientExchangeHandler Maven / Gradle / Ivy
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* to you under the Apache License, Version 2.0 (the
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* http://www.apache.org/licenses/LICENSE-2.0
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* under the License.
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*
* This software consists of voluntary contributions made by many
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*/
package org.apache.http.impl.nio.client;
import java.io.IOException;
import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicLong;
import java.util.concurrent.atomic.AtomicReference;
import org.apache.commons.logging.Log;
import org.apache.http.ConnectionClosedException;
import org.apache.http.ConnectionReuseStrategy;
import org.apache.http.HttpHost;
import org.apache.http.HttpResponse;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.methods.HttpRequestWrapper;
import org.apache.http.client.protocol.HttpClientContext;
import org.apache.http.concurrent.FutureCallback;
import org.apache.http.conn.ConnectionKeepAliveStrategy;
import org.apache.http.conn.routing.HttpRoute;
import org.apache.http.conn.routing.RouteTracker;
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.protocol.HttpContext;
import org.apache.http.util.Asserts;
/**
* Abstract {@link org.apache.http.nio.protocol.HttpAsyncClientExchangeHandler} class
* that implements connection management aspects shared by all HTTP exchange handlers.
*
* 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.
*/
abstract class AbstractClientExchangeHandler implements HttpAsyncClientExchangeHandler {
private static final AtomicLong COUNTER = new AtomicLong(1);
protected final Log log;
private final long id;
private final HttpClientContext localContext;
private final NHttpClientConnectionManager connmgr;
private final ConnectionReuseStrategy connReuseStrategy;
private final ConnectionKeepAliveStrategy keepaliveStrategy;
private final AtomicReference> connectionFutureRef;
private final AtomicReference managedConnRef;
private final AtomicReference routeRef;
private final AtomicReference routeTrackerRef;
private final AtomicBoolean routeEstablished;
private final AtomicReference validDurationRef;
private final AtomicReference requestRef;
private final AtomicReference responseRef;
private final AtomicBoolean completed;
private final AtomicBoolean closed;
AbstractClientExchangeHandler(
final Log log,
final HttpClientContext localContext,
final NHttpClientConnectionManager connmgr,
final ConnectionReuseStrategy connReuseStrategy,
final ConnectionKeepAliveStrategy keepaliveStrategy) {
super();
this.log = log;
this.id = COUNTER.getAndIncrement();
this.localContext = localContext;
this.connmgr = connmgr;
this.connReuseStrategy = connReuseStrategy;
this.keepaliveStrategy = keepaliveStrategy;
this.connectionFutureRef = new AtomicReference>(null);
this.managedConnRef = new AtomicReference(null);
this.routeRef = new AtomicReference(null);
this.routeTrackerRef = new AtomicReference(null);
this.routeEstablished = new AtomicBoolean(false);
this.validDurationRef = new AtomicReference(null);
this.requestRef = new AtomicReference(null);
this.responseRef = new AtomicReference(null);
this.completed = new AtomicBoolean(false);
this.closed = new AtomicBoolean(false);
}
final long getId() {
return this.id;
}
final boolean isCompleted() {
return this.completed.get();
}
final void markCompleted() {
this.completed.set(true);
}
final void markConnectionNonReusable() {
this.validDurationRef.set(null);
}
final boolean isRouteEstablished() {
return this.routeEstablished.get();
}
final HttpRoute getRoute() {
return this.routeRef.get();
}
final void setRoute(final HttpRoute route) {
this.routeRef.set(route);
}
final HttpRequestWrapper getCurrentRequest() {
return this.requestRef.get();
}
final void setCurrentRequest(final HttpRequestWrapper request) {
this.requestRef.set(request);
}
final HttpResponse getCurrentResponse() {
return this.responseRef.get();
}
final void setCurrentResponse(final HttpResponse response) {
this.responseRef.set(response);
}
final HttpRoute getActualRoute() {
final RouteTracker routeTracker = this.routeTrackerRef.get();
return routeTracker != null ? routeTracker.toRoute() : null;
}
final void verifytRoute() {
if (!this.routeEstablished.get() && this.routeTrackerRef.get() == null) {
final NHttpClientConnection managedConn = this.managedConnRef.get();
Asserts.check(managedConn != null, "Inconsistent state: managed connection is null");
final boolean routeComplete = this.connmgr.isRouteComplete(managedConn);
this.routeEstablished.set(routeComplete);
if (!routeComplete) {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] Start connection routing");
}
final HttpRoute route = this.routeRef.get();
this.routeTrackerRef.set(new RouteTracker(route));
} else {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] Connection route already established");
}
}
}
}
final void onRouteToTarget() throws IOException {
final NHttpClientConnection managedConn = this.managedConnRef.get();
Asserts.check(managedConn != null, "Inconsistent state: managed connection is null");
final HttpRoute route = this.routeRef.get();
Asserts.check(route != null, "Inconsistent state: HTTP route is null");
final RouteTracker routeTracker = this.routeTrackerRef.get();
Asserts.check(routeTracker != null, "Inconsistent state: HTTP route tracker");
this.connmgr.startRoute(managedConn, route, this.localContext);
routeTracker.connectTarget(route.isSecure());
}
final void onRouteToProxy() throws IOException {
final NHttpClientConnection managedConn = this.managedConnRef.get();
Asserts.check(managedConn != null, "Inconsistent state: managed connection is null");
final HttpRoute route = this.routeRef.get();
Asserts.check(route != null, "Inconsistent state: HTTP route is null");
final RouteTracker routeTracker = this.routeTrackerRef.get();
Asserts.check(routeTracker != null, "Inconsistent state: HTTP route tracker");
this.connmgr.startRoute(managedConn, route, this.localContext);
final HttpHost proxy = route.getProxyHost();
routeTracker.connectProxy(proxy, false);
}
final void onRouteUpgrade() throws IOException {
final NHttpClientConnection managedConn = this.managedConnRef.get();
Asserts.check(managedConn != null, "Inconsistent state: managed connection is null");
final HttpRoute route = this.routeRef.get();
Asserts.check(route != null, "Inconsistent state: HTTP route is null");
final RouteTracker routeTracker = this.routeTrackerRef.get();
Asserts.check(routeTracker != null, "Inconsistent state: HTTP route tracker");
this.connmgr.upgrade(managedConn, route, this.localContext);
routeTracker.layerProtocol(route.isSecure());
}
final void onRouteTunnelToTarget() {
final RouteTracker routeTracker = this.routeTrackerRef.get();
Asserts.check(routeTracker != null, "Inconsistent state: HTTP route tracker");
routeTracker.tunnelTarget(false);
}
final void onRouteComplete() {
final NHttpClientConnection managedConn = this.managedConnRef.get();
Asserts.check(managedConn != null, "Inconsistent state: managed connection is null");
final HttpRoute route = this.routeRef.get();
Asserts.check(route != null, "Inconsistent state: HTTP route is null");
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] route completed");
}
this.connmgr.routeComplete(managedConn, route, this.localContext);
this.routeEstablished.set(true);
this.routeTrackerRef.set(null);
}
final NHttpClientConnection getConnection() {
return this.managedConnRef.get();
}
final void releaseConnection() {
final NHttpClientConnection localConn = this.managedConnRef.getAndSet(null);
if (localConn != null) {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] releasing connection");
}
localConn.getContext().removeAttribute(HttpAsyncRequestExecutor.HTTP_HANDLER);
final Long validDuration = this.validDurationRef.get();
if (validDuration != null) {
final Object userToken = this.localContext.getUserToken();
this.connmgr.releaseConnection(localConn, userToken, validDuration, TimeUnit.MILLISECONDS);
} else {
try {
localConn.close();
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] connection discarded");
}
} catch (final IOException ex) {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] " + ex.getMessage(), ex);
}
} finally {
this.connmgr.releaseConnection(localConn, null, 0, TimeUnit.MILLISECONDS);
}
}
}
}
final void discardConnection() {
final NHttpClientConnection localConn = this.managedConnRef.getAndSet(null);
if (localConn != null) {
try {
localConn.shutdown();
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] connection aborted");
}
} catch (final IOException ex) {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] " + ex.getMessage(), ex);
}
} finally {
this.connmgr.releaseConnection(localConn, null, 0, TimeUnit.MILLISECONDS);
}
}
}
final boolean manageConnectionPersistence() {
final HttpResponse response = this.responseRef.get();
Asserts.check(response != null, "Inconsistent state: HTTP response");
final NHttpClientConnection managedConn = this.managedConnRef.get();
Asserts.check(managedConn != null, "Inconsistent state: managed connection is null");
final boolean keepAlive = managedConn.isOpen() &&
this.connReuseStrategy.keepAlive(response, this.localContext);
if (keepAlive) {
final long validDuration = this.keepaliveStrategy.getKeepAliveDuration(
response, this.localContext);
if (this.log.isDebugEnabled()) {
final String s;
if (validDuration > 0) {
s = "for " + validDuration + " " + TimeUnit.MILLISECONDS;
} else {
s = "indefinitely";
}
this.log.debug("[exchange: " + this.id + "] Connection can be kept alive " + s);
}
this.validDurationRef.set(validDuration);
} else {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] Connection cannot be kept alive");
}
this.validDurationRef.set(null);
}
return keepAlive;
}
private void connectionAllocated(final NHttpClientConnection managedConn) {
try {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] Connection allocated: " + managedConn);
}
this.connectionFutureRef.set(null);
this.managedConnRef.set(managedConn);
if (this.closed.get()) {
discardConnection();
return;
}
if (this.connmgr.isRouteComplete(managedConn)) {
this.routeEstablished.set(true);
this.routeTrackerRef.set(null);
}
final HttpContext context = managedConn.getContext();
synchronized (context) {
context.setAttribute(HttpAsyncRequestExecutor.HTTP_HANDLER, this);
if (managedConn.isStale()) {
failed(new ConnectionClosedException("Connection closed"));
} else {
managedConn.requestOutput();
}
}
} catch (final RuntimeException runex) {
failed(runex);
throw runex;
}
}
private void connectionRequestFailed(final Exception ex) {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] connection request failed");
}
this.connectionFutureRef.set(null);
failed(ex);
}
private void connectionRequestCancelled() {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] Connection request cancelled");
}
this.connectionFutureRef.set(null);
try {
executionCancelled();
} finally {
close();
}
}
final void requestConnection() {
final HttpRoute route = this.routeRef.get();
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] Request connection for " + route);
}
discardConnection();
this.validDurationRef.set(null);
this.routeTrackerRef.set(null);
this.routeEstablished.set(false);
final Object userToken = this.localContext.getUserToken();
final RequestConfig config = this.localContext.getRequestConfig();
this.connectionFutureRef.set(this.connmgr.requestConnection(
route,
userToken,
config.getConnectTimeout(),
config.getConnectionRequestTimeout(),
TimeUnit.MILLISECONDS,
new FutureCallback() {
@Override
public void completed(final NHttpClientConnection managedConn) {
connectionAllocated(managedConn);
}
@Override
public void failed(final Exception ex) {
connectionRequestFailed(ex);
}
@Override
public void cancelled() {
connectionRequestCancelled();
}
}));
}
abstract void releaseResources();
abstract void executionFailed(final Exception ex);
abstract boolean executionCancelled();
@Override
public final void close() {
if (this.closed.compareAndSet(false, true)) {
discardConnection();
releaseResources();
}
}
@Override
public final boolean isDone() {
return this.completed.get();
}
@Override
public final void failed(final Exception ex) {
if (this.closed.compareAndSet(false, true)) {
try {
executionFailed(ex);
} finally {
discardConnection();
releaseResources();
}
}
}
@Override
public final boolean cancel() {
if (this.log.isDebugEnabled()) {
this.log.debug("[exchange: " + this.id + "] Cancelled");
}
if (this.closed.compareAndSet(false, true)) {
try {
final Future connectionFuture = this.connectionFutureRef.getAndSet(null);
if (connectionFuture != null) {
connectionFuture.cancel(true);
}
return executionCancelled();
} finally {
discardConnection();
releaseResources();
}
}
return false;
}
}