Author: fhanik
Date: Mon Jul 20 01:20:02 2009
New Revision: 795669
URL: http://svn.apache.org/viewvc?rev=795669&view=rev
Log:
start implementing concurrency around the state machine
startAsync and complete() are to be thread safe operations
Modified:
tomcat/trunk/java/org/apache/catalina/connector/AsyncContextImpl.java
tomcat/trunk/java/org/apache/catalina/connector/Request.java
Modified: tomcat/trunk/java/org/apache/catalina/connector/AsyncContextImpl.java
URL:
http://svn.apache.org/viewvc/tomcat/trunk/java/org/apache/catalina/connector/AsyncContextImpl.java?rev=795669&r1=795668&r2=795669&view=diff
==============================================================================
--- tomcat/trunk/java/org/apache/catalina/connector/AsyncContextImpl.java
(original)
+++ tomcat/trunk/java/org/apache/catalina/connector/AsyncContextImpl.java Mon
Jul 20 01:20:02 2009
@@ -19,6 +19,7 @@
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
+import java.util.concurrent.atomic.AtomicReference;
import javax.servlet.AsyncContext;
import javax.servlet.AsyncListener;
@@ -30,6 +31,7 @@
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
+import org.apache.catalina.Context;
import org.apache.coyote.ActionCode;
import org.apache.juli.logging.Log;
import org.apache.juli.logging.LogFactory;
@@ -39,15 +41,20 @@
*
*/
public class AsyncContextImpl implements AsyncContext {
+
+ public static enum AsyncState {
+ NOT_STARTED, STARTED, DISPATCHING, DISPATCHED, COMPLETING
+ };
+
protected static Log log = LogFactory.getLog(AsyncContextImpl.class);
- private boolean started = false;
private ServletRequest servletRequest = null;
private ServletResponse servletResponse = null;
private List<AsyncListenerWrapper> listeners = new
ArrayList<AsyncListenerWrapper>();
private boolean hasOriginalRequestAndResponse = true;
- private boolean completed = true;
private volatile Runnable dispatch = null;
+ private Context context = null;
+ private AtomicReference<AsyncState> state = new
AtomicReference<AsyncState>();
private Request request;
@@ -77,31 +84,35 @@
@Override
public void dispatch(ServletContext context, String path) {
// TODO SERVLET3 - async
- // TODO SERVLET3 - async
- if (request.getAttribute(ASYNC_REQUEST_URI)==null) {
- request.setAttribute(ASYNC_REQUEST_URI, request.getRequestURI());
- request.setAttribute(ASYNC_CONTEXT_PATH, request.getContextPath());
- request.setAttribute(ASYNC_SERVLET_PATH, request.getServletPath());
- request.setAttribute(ASYNC_QUERY_STRING, request.getQueryString());
- }
- final RequestDispatcher requestDispatcher =
context.getRequestDispatcher(path);
- final HttpServletRequest servletRequest =
(HttpServletRequest)getRequest();
- final HttpServletResponse servletResponse =
(HttpServletResponse)getResponse();
- Runnable run = new Runnable() {
- public void run() {
- try {
- //piggy back on the request dispatcher to ensure that
filters etc get called.
- //TODO SERVLET3 - async should this be include/forward or
a new dispatch type
- //javadoc suggests include with the type of
DispatcherType.ASYNC
- requestDispatcher.include(servletRequest, servletResponse);
- }catch (Exception x) {
- //log.error("Async.dispatch",x);
- throw new RuntimeException(x);
- }
+ if (this.state.compareAndSet(AsyncState.STARTED,
AsyncState.DISPATCHING)) {
+ if (request.getAttribute(ASYNC_REQUEST_URI)==null) {
+ request.setAttribute(ASYNC_REQUEST_URI,
request.getRequestURI());
+ request.setAttribute(ASYNC_CONTEXT_PATH,
request.getContextPath());
+ request.setAttribute(ASYNC_SERVLET_PATH,
request.getServletPath());
+ request.setAttribute(ASYNC_QUERY_STRING,
request.getQueryString());
}
- };
- this.dispatch = run;
- request.coyoteRequest.action(ActionCode.ACTION_ASYNC_DISPATCH, null );
+ final RequestDispatcher requestDispatcher =
context.getRequestDispatcher(path);
+ final HttpServletRequest servletRequest =
(HttpServletRequest)getRequest();
+ final HttpServletResponse servletResponse =
(HttpServletResponse)getResponse();
+ Runnable run = new Runnable() {
+ public void run() {
+ try {
+ //piggy back on the request dispatcher to ensure that
filters etc get called.
+ //TODO SERVLET3 - async should this be include/forward
or a new dispatch type
+ //javadoc suggests include with the type of
DispatcherType.ASYNC
+ requestDispatcher.include(servletRequest,
servletResponse);
+ }catch (Exception x) {
+ //log.error("Async.dispatch",x);
+ throw new RuntimeException(x);
+ }
+ }
+ };
+ this.dispatch = run;
+ request.coyoteRequest.action(ActionCode.ACTION_ASYNC_DISPATCH,
null );
+
+ } else {
+ throw new IllegalStateException("Dispatch not allowed. Invalid
state:"+state.get());
+ }
}
@Override
@@ -139,20 +150,24 @@
protected void recycle() {
- started = false;
servletRequest = null;
servletResponse = null;
listeners.clear();
hasOriginalRequestAndResponse = true;
- completed = true;
+ state.set(AsyncState.NOT_STARTED);
+ context = null;
}
public boolean isStarted() {
- return started;
+ return (state.get()!=AsyncState.NOT_STARTED);
}
- public void setStarted(boolean started) {
- this.started = started;
+ public void setStarted(Context context) {
+ if (state.compareAndSet(AsyncState.NOT_STARTED, AsyncState.STARTED)) {
+ this.context = context;
+ } else {
+ throw new IllegalStateException("Already started.");
+ }
}
public ServletRequest getServletRequest() {
@@ -181,47 +196,59 @@
}
public boolean isCompleted() {
- return completed;
+ return (state.get()==AsyncState.NOT_STARTED);
}
- public void setCompleted(boolean completed) {
- this.completed = completed;
+ public void setCompleted() {
+ this.state.set(AsyncState.NOT_STARTED);
}
public void doInternalDispatch() throws ServletException, IOException {
- if (this.dispatch!=null) {
- try {
- dispatch.run();
- } catch (RuntimeException x) {
- doInternalComplete(true);
- if (x.getCause() instanceof ServletException) throw
(ServletException)x.getCause();
- if (x.getCause() instanceof IOException) throw
(IOException)x.getCause();
- else throw new ServletException(x);
- } finally {
- dispatch = null;
+ if (this.state.compareAndSet(AsyncState.DISPATCHING,
AsyncState.DISPATCHED)) {
+ if (this.dispatch!=null) {
+ try {
+ dispatch.run();
+ } catch (RuntimeException x) {
+ doInternalComplete(true);
+ if (x.getCause() instanceof ServletException) throw
(ServletException)x.getCause();
+ if (x.getCause() instanceof IOException) throw
(IOException)x.getCause();
+ else throw new ServletException(x);
+ } finally {
+ dispatch = null;
+ }
}
+ } else {
+ throw new IllegalStateException("Dispatch illegal. Invalid state:
"+state.get());
}
}
public void doInternalComplete(boolean error) {
if (isCompleted()) return;
- for (AsyncListenerWrapper wrapper : listeners) {
+ if (state.compareAndSet(AsyncState.STARTED, AsyncState.NOT_STARTED)) {
+ //this is the same as
+ //request.startAsync().complete();
+ recycle();
+ } else if (state.compareAndSet(AsyncState.DISPATCHED,
AsyncState.NOT_STARTED)) {
+ for (AsyncListenerWrapper wrapper : listeners) {
+ try {
+ wrapper.fireOnComplete();
+ }catch (IOException x) {
+ //how does this propagate, or should it?
+ //TODO SERVLET3 - async
+ log.error("",x);
+ }
+ }
try {
- wrapper.fireOnComplete();
- }catch (IOException x) {
- //how does this propagate, or should it?
- //TODO SERVLET3 - async
+ if (!error) getResponse().flushBuffer();
+
+ }catch (Exception x) {
log.error("",x);
}
+
request.coyoteRequest.action(ActionCode.ACTION_ASYNC_COMPLETE,null);
+ recycle();
+ } else {
+ throw new IllegalStateException("Complete illegal. Invalid
state:"+state.get());
}
- try {
- if (!error) getResponse().flushBuffer();
-
- }catch (Exception x) {
- log.error("",x);
- }
- request.coyoteRequest.action(ActionCode.ACTION_ASYNC_COMPLETE,null);
- recycle();
}
}
Modified: tomcat/trunk/java/org/apache/catalina/connector/Request.java
URL:
http://svn.apache.org/viewvc/tomcat/trunk/java/org/apache/catalina/connector/Request.java?rev=795669&r1=795668&r2=795669&view=diff
==============================================================================
--- tomcat/trunk/java/org/apache/catalina/connector/Request.java (original)
+++ tomcat/trunk/java/org/apache/catalina/connector/Request.java Mon Jul 20
01:20:02 2009
@@ -1466,8 +1466,7 @@
else if (asyncContext.isStarted()) throw new
IllegalStateException("Already started.");
asyncContext.setServletRequest(getRequest());
asyncContext.setServletResponse(response.getResponse());
- asyncContext.setStarted(true);
- asyncContext.setCompleted(false);
+ asyncContext.setStarted(getContext());
return asyncContext;
}
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