/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright (c) 1997-2011 Oracle and/or its affiliates. All rights reserved.
*
* The contents of this file are subject to the terms of either the GNU
* General Public License Version 2 only ("GPL") or the Common Development
* and Distribution License("CDDL") (collectively, the "License"). You
* may not use this file except in compliance with the License. You can
* obtain a copy of the License at
* https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
* or packager/legal/LICENSE.txt. See the License for the specific
* language governing permissions and limitations under the License.
*
* When distributing the software, include this License Header Notice in each
* file and include the License file at packager/legal/LICENSE.txt.
*
* GPL Classpath Exception:
* Oracle designates this particular file as subject to the "Classpath"
* exception as provided by Oracle in the GPL Version 2 section of the License
* file that accompanied this code.
*
* Modifications:
* If applicable, add the following below the License Header, with the fields
* enclosed by brackets [] replaced by your own identifying information:
* "Portions Copyright [year] [name of copyright owner]"
*
* Contributor(s):
* If you wish your version of this file to be governed by only the CDDL or
* only the GPL Version 2, indicate your decision by adding "[Contributor]
* elects to include this software in this distribution under the [CDDL or GPL
* Version 2] license." If you don't indicate a single choice of license, a
* recipient has the option to distribute your version of this file under
* either the CDDL, the GPL Version 2 or to extend the choice of license to
* its licensees as provided above. However, if you add GPL Version 2 code
* and therefore, elected the GPL Version 2 license, then the option applies
* only if the new code is made subject to such option by the copyright
* holder.
*/
package org.apache.catalina.connector;
import org.apache.catalina.Globals;
import org.apache.catalina.core.ApplicationDispatcher;
import org.apache.catalina.core.ApplicationHttpRequest;
import org.apache.catalina.core.ApplicationHttpResponse;
import org.apache.catalina.core.DispatchTargetsInfo;
import org.apache.catalina.core.StandardContext;
import org.apache.catalina.util.StringManager;
import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import java.io.IOException;
import java.util.LinkedList;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.logging.Level;
import java.util.logging.Logger;
class AsyncContextImpl implements AsyncContext {
/*
* Event notification types for async mode
*/
static enum AsyncEventType { COMPLETE, TIMEOUT, ERROR, START_ASYNC }
private static final Logger log =
Logger.getLogger(AsyncContextImpl.class.getName());
// Default timeout for async operations
private static final long DEFAULT_ASYNC_TIMEOUT_MILLIS = 30000L;
// Thread pool for async dispatches
private static final ExecutorService pool =
Executors.newCachedThreadPool(new AsyncPoolThreadFactory());
private static final StringManager STRING_MANAGER =
StringManager.getManager(Constants.Package);
// The original (unwrapped) request
private Request origRequest;
// The possibly wrapped request passed to ServletRequest.startAsync
private ServletRequest servletRequest;
// The possibly wrapped response passed to ServletRequest.startAsync
private ServletResponse servletResponse;
private boolean isOriginalRequestAndResponse = false;
private boolean isStartAsyncWithZeroArg = false;
// defaults to false
private AtomicBoolean isDispatchInProgress = new AtomicBoolean();
private ThreadLocal<Boolean> isDispatchInScope = new ThreadLocal<Boolean>() {
@Override
protected Boolean initialValue() {
return Boolean.FALSE;
}
};
private AtomicBoolean isOkToConfigure = new AtomicBoolean(true);
private long asyncTimeoutMillis = DEFAULT_ASYNC_TIMEOUT_MILLIS;
private final LinkedList<AsyncListenerContext> asyncListenerContexts =
new LinkedList<AsyncListenerContext>();
// The number of times this AsyncContext has been reinitialized via a call
// to ServletRequest#startAsync
private AtomicInteger startAsyncCounter = new AtomicInteger(0);
private ThreadLocal<Boolean> isStartAsyncInScope = new ThreadLocal<Boolean>() {
@Override
protected Boolean initialValue() {
return Boolean.FALSE;
}
};
/**
* Constructor
*
* @param origRequest the original (unwrapped) request
* @param servletRequest the possibly wrapped request passed to
* ServletRequest.startAsync
* @param servletResponse the possibly wrapped response passed to
* ServletRequest.startAsync
* @param isStartAsyncWithZeroArg true if the zero-arg version of
* startAsync was called, false otherwise
*/
AsyncContextImpl(Request origRequest,
ServletRequest servletRequest,
Response origResponse,
ServletResponse servletResponse,
boolean isStartAsyncWithZeroArg) {
this.origRequest = origRequest;
init(servletRequest, servletResponse, isStartAsyncWithZeroArg);
}
@Override
public ServletRequest getRequest() {
return servletRequest;
}
Request getOriginalRequest() {
return origRequest;
}
@Override
public ServletResponse getResponse() {
return servletResponse;
}
@Override
public boolean hasOriginalRequestAndResponse() {
return isOriginalRequestAndResponse;
}
@Override
public void dispatch() {
ApplicationDispatcher dispatcher =
(ApplicationDispatcher)getZeroArgDispatcher(
origRequest, servletRequest, isStartAsyncWithZeroArg);
isDispatchInScope.set(true);
if (dispatcher != null) {
if (isDispatchInProgress.compareAndSet(false, true)) {
pool.execute(new Handler(this, dispatcher, origRequest));
} else {
throw new IllegalStateException(
STRING_MANAGER.getString("async.dispatchInProgress"));
}
} else {
// Should never happen, because any unmapped paths will be
// mapped to the DefaultServlet
log.warning("Unable to determine target of zero-arg dispatcher");
}
}
@Override
public void dispatch(String path) {
if (path == null) {
throw new IllegalArgumentException("Null path");
}
ApplicationDispatcher dispatcher = (ApplicationDispatcher)
servletRequest.getRequestDispatcher(path);
isDispatchInScope.set(true);
if (dispatcher != null) {
if (isDispatchInProgress.compareAndSet(false, true)) {
pool.execute(new Handler(this, dispatcher, origRequest));
} else {
throw new IllegalStateException(
STRING_MANAGER.getString("async.dispatchInProgress"));
}
} else {
// Should never happen, because any unmapped paths will be
// mapped to the DefaultServlet
log.warning("Unable to acquire RequestDispatcher for " +
path);
}
}
@Override
public void dispatch(ServletContext context, String path) {
if (path == null || context == null) {
throw new IllegalArgumentException("Null context or path");
}
ApplicationDispatcher dispatcher = (ApplicationDispatcher)
context.getRequestDispatcher(path);
isDispatchInScope.set(true);
if (dispatcher != null) {
if (isDispatchInProgress.compareAndSet(false, true)) {
pool.execute(new Handler(this, dispatcher, origRequest));
} else {
throw new IllegalStateException(
STRING_MANAGER.getString("async.dispatchInProgress"));
}
} else {
// Should never happen, because any unmapped paths will be
// mapped to the DefaultServlet
log.warning("Unable to acquire RequestDispatcher for " + path +
"in servlet context " + context.getContextPath());
}
}
boolean isDispatchInScope() {
return isDispatchInScope.get();
}
boolean getAndResetDispatchInScope() {
final boolean flag = isDispatchInScope.get();
isDispatchInScope.set(Boolean.FALSE);
return flag;
}
@Override
public void complete() {
origRequest.asyncComplete();
}
@Override
public void start(Runnable run) {
pool.execute(run);
}
@Override
public void addListener(AsyncListener listener) {
if (listener == null) {
throw new IllegalArgumentException("Null listener");
}
if (!isOkToConfigure.get()) {
throw new IllegalStateException(
STRING_MANAGER.getString("async.addListenerIllegalState"));
}
synchronized(asyncListenerContexts) {
asyncListenerContexts.add(new AsyncListenerContext(listener));
}
}
@Override
public void addListener(AsyncListener listener,
ServletRequest servletRequest,
ServletResponse servletResponse) {
if (listener == null || servletRequest == null ||
servletResponse == null) {
throw new IllegalArgumentException(
"Null listener, request, or response");
}
if (!isOkToConfigure.get()) {
throw new IllegalStateException(
STRING_MANAGER.getString("async.addListenerIllegalState"));
}
synchronized(asyncListenerContexts) {
asyncListenerContexts.add(new AsyncListenerContext(
listener, servletRequest, servletResponse));
}
}
@Override
public <T extends AsyncListener> T createListener(Class<T> clazz)
throws ServletException {
T listener = null;
StandardContext ctx = (StandardContext) origRequest.getContext();
if (ctx != null) {
try {
listener = ctx.createListenerInstance(clazz);
} catch (Throwable t) {
throw new ServletException(t);
}
}
return listener;
}
@Override
public void setTimeout(long timeout) {
if (!isOkToConfigure.get()) {
throw new IllegalStateException(
STRING_MANAGER.getString("async.setTimeoutIllegalState"));
}
asyncTimeoutMillis = timeout;
origRequest.setAsyncTimeout(timeout);
}
@Override
public long getTimeout() {
return asyncTimeoutMillis;
}
/*
* Reinitializes this AsyncContext with the given request and response.
*
* @param servletRequest the ServletRequest with which to initialize
* the AsyncContext
* @param servletResponse the ServletResponse with which to initialize
* the AsyncContext
* @param isStartAsyncWithZeroArg true if the zero-arg version of
* startAsync was called, false otherwise
*/
void reinitialize(ServletRequest servletRequest,
ServletResponse servletResponse,
boolean isStartAsyncWithZeroArg) {
init(servletRequest, servletResponse, isStartAsyncWithZeroArg);
isDispatchInProgress.set(false);
setOkToConfigure(true);
startAsyncCounter.incrementAndGet();
notifyAsyncListeners(AsyncEventType.START_ASYNC, null);
}
/**
* @param value true if calls to AsyncContext#addListener and
* AsyncContext#setTimeout will be accepted, and false if these
* calls will result in an IllegalStateException
*/
void setOkToConfigure(boolean value) {
isOkToConfigure.set(value);
}
private void init(ServletRequest servletRequest,
ServletResponse servletResponse, boolean isStartAsyncWithZeroArg) {
this.servletRequest = servletRequest;
this.servletResponse = servletResponse;
// If original or container-wrapped request and response,
// AsyncContext#hasOriginalRequestAndResponse must return true;
// false otherwise (i.e., if application-wrapped)
this.isOriginalRequestAndResponse =
((servletRequest instanceof RequestFacade ||
servletRequest instanceof ApplicationHttpRequest) &&
(servletResponse instanceof ResponseFacade ||
servletResponse instanceof ApplicationHttpResponse));
this.isStartAsyncWithZeroArg = isStartAsyncWithZeroArg;
}
/**
* Determines the dispatcher of a zero-argument async dispatch for the
* given request.
*
* @return the dispatcher of the zero-argument async dispatch
*/
private RequestDispatcher getZeroArgDispatcher(
Request origRequest, ServletRequest servletRequest,
boolean isStartAsyncWithZeroArg) {
String dispatchTarget = null;
boolean isNamed = false;
if ((!isStartAsyncWithZeroArg) &&
servletRequest instanceof HttpServletRequest) {
HttpServletRequest req = (HttpServletRequest)servletRequest;
dispatchTarget = getCombinedPath(req);
} else {
DispatchTargetsInfo dtInfo = (DispatchTargetsInfo)origRequest.getAttribute(
ApplicationDispatcher.LAST_DISPATCH_REQUEST_PATH_ATTR);
if (dtInfo != null) {
dispatchTarget = dtInfo.getLastDispatchTarget();
isNamed = dtInfo.isLastNamedDispatchTarget();
}
if (dispatchTarget == null) {
dispatchTarget = getCombinedPath(origRequest);
}
}
RequestDispatcher dispatcher = null;
if (dispatchTarget != null) {
dispatcher = ((isNamed) ?
servletRequest.getServletContext().getNamedDispatcher(dispatchTarget) :
servletRequest.getRequestDispatcher(dispatchTarget));
}
return dispatcher;
}
private String getCombinedPath(HttpServletRequest req) {
String servletPath = req.getServletPath();
if (servletPath == null) {
return null;
}
String pathInfo = req.getPathInfo();
if (pathInfo == null) {
return servletPath;
}
return servletPath + pathInfo;
}
static class Handler implements Runnable {
private final AsyncContextImpl asyncContext;
private final ApplicationDispatcher dispatcher;
private final Request origRequest;
Handler(AsyncContextImpl asyncContext,
ApplicationDispatcher dispatcher,
Request origRequest) {
this.asyncContext = asyncContext;
this.dispatcher = dispatcher;
this.origRequest = origRequest;
}
@Override
public void run() {
asyncContext.isStartAsyncInScope.set(Boolean.TRUE);
origRequest.setAttribute(Globals.DISPATCHER_TYPE_ATTR,
DispatcherType.ASYNC);
origRequest.setAsyncStarted(false);
int startAsyncCurrent = asyncContext.startAsyncCounter.get();
try {
dispatcher.dispatch(asyncContext.getRequest(),
asyncContext.getResponse(), DispatcherType.ASYNC);
/*
* Close the response after the dispatch target has
* completed execution, unless the dispatch target has called
* ServletRequest#startAsync, in which case the AsyncContext's
* startAsyncCounter will be greater than it was before the
* dispatch
*/
if (asyncContext.startAsyncCounter.compareAndSet(
startAsyncCurrent, startAsyncCurrent)) {
asyncContext.complete();
}
} catch (Throwable t) {
asyncContext.notifyAsyncListeners(AsyncEventType.ERROR, t);
asyncContext.getOriginalRequest().errorDispatchAndComplete(t);
} finally {
asyncContext.isStartAsyncInScope.set(Boolean.FALSE);
}
}
}
boolean isStartAsyncInScope() {
return isStartAsyncInScope.get().booleanValue();
}
/*
* Notifies all AsyncListeners of the given async event type
*/
void notifyAsyncListeners(AsyncEventType asyncEventType, Throwable t) {
synchronized(asyncListenerContexts) {
if (asyncListenerContexts.isEmpty()) {
return;
}
LinkedList<AsyncListenerContext> clone =
new LinkedList<AsyncListenerContext>(asyncListenerContexts);
if (asyncEventType.equals(AsyncEventType.START_ASYNC)) {
asyncListenerContexts.clear();
}
for (AsyncListenerContext asyncListenerContext : clone) {
AsyncListener asyncListener =
asyncListenerContext.getAsyncListener();
AsyncEvent asyncEvent = new AsyncEvent(
this, asyncListenerContext.getRequest(),
asyncListenerContext.getResponse(), t);
try {
switch (asyncEventType) {
case COMPLETE:
asyncListener.onComplete(asyncEvent);
break;
case TIMEOUT:
asyncListener.onTimeout(asyncEvent);
break;
case ERROR:
asyncListener.onError(asyncEvent);
break;
case START_ASYNC:
asyncListener.onStartAsync(asyncEvent);
break;
}
} catch (IOException ioe) {
log.log(Level.WARNING, "Error invoking AsyncListener",
ioe);
}
}
}
}
void clear() {
synchronized(asyncListenerContexts) {
asyncListenerContexts.clear();
}
}
/**
* Class holding all the information required for invoking an
* AsyncListener (including the AsyncListener itself).
*/
private static class AsyncListenerContext {
private AsyncListener listener;
private ServletRequest request;
private ServletResponse response;
public AsyncListenerContext(AsyncListener listener) {
this(listener, null, null);
}
public AsyncListenerContext(AsyncListener listener,
ServletRequest request,
ServletResponse response) {
this.listener = listener;
this.request = request;
this.response = response;
}
public AsyncListener getAsyncListener() {
return listener;
}
public ServletRequest getRequest() {
return request;
}
public ServletResponse getResponse() {
return response;
}
}
private static final class AsyncPoolThreadFactory implements ThreadFactory {
private final ThreadFactory defaultFactory = Executors.defaultThreadFactory();
private final AtomicInteger counter = new AtomicInteger(0);
// ------------------------------------------ Methods from ThreadFactory
@Override
public Thread newThread(Runnable r) {
final Thread t = defaultFactory.newThread(r);
t.setName("glassfish-web-async-thread-" + counter.incrementAndGet());
return t;
}
} // END AsyncPoolThreadFactory
}