Author: rich
Date: Tue Sep 28 22:44:48 2004
New Revision: 47464
Modified:
incubator/beehive/trunk/netui/src/compiler/org/apache/beehive/netui/compiler/PageFlowChecker.java
incubator/beehive/trunk/netui/src/pageflow/org/apache/beehive/netui/pageflow/FacesBackingBean.java
incubator/beehive/trunk/netui/src/pageflow/org/apache/beehive/netui/pageflow/FlowController.java
incubator/beehive/trunk/netui/src/pageflow/org/apache/beehive/netui/pageflow/PageFlowController.java
incubator/beehive/trunk/netui/src/pageflow/org/apache/beehive/netui/pageflow/PageFlowManagedObject.java
incubator/beehive/trunk/netui/src/pageflow/org/apache/beehive/netui/pageflow/SharedFlowController.java
Log:
- Fixed a concurrency bug, where a page flow's destroy() callback (which calls
the user's onDestroy() and does internal uninitialization of things like
Control member fields) could overlap the execution of an action method
triggered by another request. The problem was the lack of synchronization on
destroy(). It is unsafe to synchronize FlowController.destroy() because it is
invoked from a session binding listener; depending on the Servlet container,
the session itself may be locked, and this risks a deadlock in the situation
where in another request thread our framework synchronizes on the page flow
instance and then invokes user code that may (directly or indirectly)
synchronize on the session. Our solution is synchronization on the page flow
instance *surrounding* any call that will remove/replace the instance in the
session. It's OK to trigger the session binding listener while the page flow
is locked. Bottom line: we always synchronize on the page flow instance before
synchronizing on the session, and never allow it to go the other direction.
- Fixed another concurrency issue that occured when a page flow was requested
while another of the same type was being destroyed. A new instance of the page
flow was (correctly) created, but because the previous one had not yet fully
uninitialized, the new one was trying to initialize Controls with IDs that
overlapped those from the old instance (being destroyed). The fix for this was
simply to ensure that the Control IDs are always instance-specific, instead of
being merely specific to the page flow and Control types.
DRT: netui (WinXP)
BB: self (linux)
Modified:
incubator/beehive/trunk/netui/src/compiler/org/apache/beehive/netui/compiler/PageFlowChecker.java
==============================================================================
---
incubator/beehive/trunk/netui/src/compiler/org/apache/beehive/netui/compiler/PageFlowChecker.java
(original)
+++
incubator/beehive/trunk/netui/src/compiler/org/apache/beehive/netui/compiler/PageFlowChecker.java
Tue Sep 28 22:44:48 2004
@@ -150,7 +150,11 @@
{
File file = CompilerUtils.getOriginalFile( classDecl );
- if ( ! jpfFile.equals( file ) )
+ //
+ // Add the dependency if it's a different file and if the file
exists (it may have been deleted
+ // sometime after the list of classes in this package got
built.
+ //
+ if ( ! jpfFile.equals( file ) && file.exists() )
{
overlapping.add( file.getName() );
overlappingFiles.add( file );
Modified:
incubator/beehive/trunk/netui/src/pageflow/org/apache/beehive/netui/pageflow/FacesBackingBean.java
==============================================================================
---
incubator/beehive/trunk/netui/src/pageflow/org/apache/beehive/netui/pageflow/FacesBackingBean.java
(original)
+++
incubator/beehive/trunk/netui/src/pageflow/org/apache/beehive/netui/pageflow/FacesBackingBean.java
Tue Sep 28 22:44:48 2004
@@ -25,6 +25,7 @@
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
+import javax.servlet.http.HttpSession;
import javax.servlet.ServletContext;
import java.util.Map;
import java.util.Collections;
@@ -42,6 +43,12 @@
{
HttpServletRequest unwrappedRequest = PageFlowUtils.unwrapMultipart(
request );
ScopedServletUtils.setScopedSessionAttr(
InternalConstants.FACES_BACKING_ATTR, this, unwrappedRequest );
+ }
+
+ protected void deleteFromSession( HttpServletRequest request )
+ {
+ HttpServletRequest unwrappedRequest = PageFlowUtils.unwrapMultipart(
request );
+ ScopedServletUtils.removeScopedSessionAttr(
InternalConstants.FACES_BACKING_ATTR, unwrappedRequest );
}
public void ensureFailover( HttpServletRequest request )
Modified:
incubator/beehive/trunk/netui/src/pageflow/org/apache/beehive/netui/pageflow/FlowController.java
==============================================================================
---
incubator/beehive/trunk/netui/src/pageflow/org/apache/beehive/netui/pageflow/FlowController.java
(original)
+++
incubator/beehive/trunk/netui/src/pageflow/org/apache/beehive/netui/pageflow/FlowController.java
Tue Sep 28 22:44:48 2004
@@ -1208,6 +1208,11 @@
{
}
+ protected void delete()
+ {
+ deleteFromSession( getRequest() );
+ }
+
/**
* Used by derived classes to store information on the most recent action
executed.
*/
Modified:
incubator/beehive/trunk/netui/src/pageflow/org/apache/beehive/netui/pageflow/PageFlowController.java
==============================================================================
---
incubator/beehive/trunk/netui/src/pageflow/org/apache/beehive/netui/pageflow/PageFlowController.java
(original)
+++
incubator/beehive/trunk/netui/src/pageflow/org/apache/beehive/netui/pageflow/PageFlowController.java
Tue Sep 28 22:44:48 2004
@@ -20,6 +20,7 @@
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSessionBindingEvent;
+import javax.servlet.http.HttpSession;
import javax.servlet.ServletContext;
import java.lang.reflect.Field;
@@ -139,10 +140,8 @@
/**
* Remove this instance from the session.
*/
- protected void delete()
+ protected synchronized void deleteFromSession( HttpServletRequest request )
{
- HttpServletRequest request = getRequest();
-
// This request attribute is used in persistInSession to prevent
re-saving of this instance.
request.setAttribute( DELETING_PAGEFLOW_ATTR, this );
@@ -168,7 +167,23 @@
void persistInSession( HttpServletRequest request, HttpServletResponse
response, ServletContext servletContext )
{
- InternalUtils.setCurrentPageFlow( this, request );
+ PageFlowController currentPageFlow = PageFlowUtils.getCurrentPageFlow(
request );
+
+ if ( currentPageFlow != null && ! currentPageFlow.isOnNestingStack() )
+ {
+ //
+ // We're going to be implicitly destroying the current page flow.
Synchronize on it so we don't mess
+ // with concurrent requests.
+ //
+ synchronized ( currentPageFlow )
+ {
+ InternalUtils.setCurrentPageFlow( this, request );
+ }
+ }
+ else
+ {
+ InternalUtils.setCurrentPageFlow( this, request );
+ }
}
/**
@@ -630,6 +645,10 @@
}
}
+ private boolean isOnNestingStack()
+ {
+ return _isOnNestingStack;
+ }
/**
* Callback when this page flow is removed from the user session. Causes
[EMAIL PROTECTED] #onDestroy}
Modified:
incubator/beehive/trunk/netui/src/pageflow/org/apache/beehive/netui/pageflow/PageFlowManagedObject.java
==============================================================================
---
incubator/beehive/trunk/netui/src/pageflow/org/apache/beehive/netui/pageflow/PageFlowManagedObject.java
(original)
+++
incubator/beehive/trunk/netui/src/pageflow/org/apache/beehive/netui/pageflow/PageFlowManagedObject.java
Tue Sep 28 22:44:48 2004
@@ -43,12 +43,12 @@
{
private static final Logger _log = Logger.getInstance(
PageFlowManagedObject.class );
-
/**
* Reference to the current ServletContext.
*/
private transient ServletContext _servletContext;
+
/**
* Initialize transient data that may have been lost during session
failover.
* @exclude public for Portal
@@ -106,11 +106,9 @@
}
/**
- * Remove this instance from the session. The base implementation does
not do anything.
+ * Remove this instance from the session.
*/
- protected void delete()
- {
- }
+ protected abstract void deleteFromSession( HttpServletRequest request );
/**
* Stores this object in the user session, in the appropriate place.
@@ -142,6 +140,7 @@
request = PageFlowUtils.unwrapMultipart( request );
ControlBeanContext beanContext =
JavaControlUtils.getControlBeanContext( request, response, false );
assert beanContext != null : "ControlBeanContext was not initialized
by PageFlowRequestProcessor";
+ String classID = getClass().getName();
for ( Iterator i = controlFields.entrySet().iterator(); i.hasNext(); )
{
@@ -166,7 +165,7 @@
PropertyMap propertyMap = ( PropertyMap ) entry.getValue();
Class fieldType = field.getType();
- String controlID = getControlID( field, request );
+ String controlID = getControlID( field, classID );
boolean isControlBeanClass = ! fieldType.isInterface();
ControlBean bean = JavaControlUtils.createControl(
fieldType.getName(), isControlBeanClass,
controlID, propertyMap, beanContext );
@@ -184,15 +183,12 @@
/**
* Create a unique ID for a given Java Control field.
*/
- private String getControlID( Field controlField, HttpServletRequest
request )
+ private String getControlID( Field controlField, String classID )
{
StringBuilder controlID = new StringBuilder();
- ScopedRequest scopedRequest = ScopedServletUtils.unwrapRequest(
request );
-
- // If this is a ScopedRequest, include the request's scope key in the
control ID.
- if ( scopedRequest != null ) controlID.append(
scopedRequest.getScopeKey() ).append( ':' );
- controlID.append( getClass().getName() ).append( '.' );
- controlID.append( controlField.getName() );
+ controlID.append( classID ); //
classname
+ controlID.append( '@' ).append( hashCode() ); //
instance ID
+ controlID.append( '.' ).append( controlField.getName() ); // name
of the control field
return controlID.toString();
}
Modified:
incubator/beehive/trunk/netui/src/pageflow/org/apache/beehive/netui/pageflow/SharedFlowController.java
==============================================================================
---
incubator/beehive/trunk/netui/src/pageflow/org/apache/beehive/netui/pageflow/SharedFlowController.java
(original)
+++
incubator/beehive/trunk/netui/src/pageflow/org/apache/beehive/netui/pageflow/SharedFlowController.java
Tue Sep 28 22:44:48 2004
@@ -23,6 +23,7 @@
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
+import javax.servlet.http.HttpSession;
import javax.servlet.ServletContext;
import org.apache.beehive.netui.pageflow.internal.InternalUtils;
@@ -123,8 +124,8 @@
/**
* Remove this instance from the session.
*/
- protected void delete()
+ protected synchronized void deleteFromSession( HttpServletRequest request )
{
- PageFlowUtils.deleteSharedFlow( getClass().getName(), getRequest() );
+ PageFlowUtils.deleteSharedFlow( getClass().getName(), request );
}
}
