Revision: 10272
Author: [email protected]
Date: Fri Jun 3 08:57:30 2011
Log: Add armor for exceptions thrown by Activity#onCancel
Review at http://gwt-code-reviews.appspot.com/1446816
http://code.google.com/p/google-web-toolkit/source/detail?r=10272
Modified:
/trunk/user/src/com/google/gwt/activity/shared/ActivityManager.java
/trunk/user/test/com/google/gwt/activity/shared/ActivityManagerTest.java
=======================================
--- /trunk/user/src/com/google/gwt/activity/shared/ActivityManager.java Mon
Apr 18 13:47:45 2011
+++ /trunk/user/src/com/google/gwt/activity/shared/ActivityManager.java Fri
Jun 3 08:57:30 2011
@@ -95,13 +95,12 @@
* be minimized by decent caching. Perenially slow activities might
mitigate
* this by providing a widget immediately, with some kind of "loading"
* treatment.
- *
- * @see
com.google.gwt.place.shared.PlaceChangeEvent.Handler#onPlaceChange(PlaceChangeEvent)
*/
public void onPlaceChange(PlaceChangeEvent event) {
Activity nextActivity = getNextActivity(event);
Throwable caughtOnStop = null;
+ Throwable caughtOnCancel = null;
Throwable caughtOnStart = null;
if (nextActivity == null) {
@@ -115,7 +114,7 @@
if (startingNext) {
// The place changed again before the new current activity showed its
// widget
- currentActivity.onCancel();
+ caughtOnCancel = tryStopOrCancel(false);
currentActivity = NULL_ACTIVITY;
startingNext = false;
} else if (!currentActivity.equals(NULL_ACTIVITY)) {
@@ -126,46 +125,26 @@
* them accidentally firing as a side effect of its tear down
*/
stopperedEventBus.removeHandlers();
-
- try {
- currentActivity.onStop();
- } catch (Throwable t) {
- caughtOnStop = t;
- } finally {
- /*
- * And kill them off again in case it was naughty and added new
ones
- * during onstop
- */
- stopperedEventBus.removeHandlers();
- }
+ caughtOnStop = tryStopOrCancel(true);
}
currentActivity = nextActivity;
if (currentActivity.equals(NULL_ACTIVITY)) {
showWidget(null);
- return;
- }
-
- startingNext = true;
-
- /*
- * Now start the thing. Wrap the actual display with a per-call
instance
- * that protects the display from canceled or stopped activities, and
which
- * maintains our startingNext state.
- */
- try {
- currentActivity.start(new ProtectedDisplay(currentActivity),
- stopperedEventBus);
- } catch (Throwable t) {
- caughtOnStart = t;
- }
-
- if (caughtOnStart != null || caughtOnStop != null) {
+ } else {
+ startingNext = true;
+ caughtOnStart = tryStart();
+ }
+
+ if (caughtOnStart != null || caughtOnCancel != null || caughtOnStop !=
null) {
Set<Throwable> causes = new LinkedHashSet<Throwable>();
if (caughtOnStop != null) {
causes.add(caughtOnStop);
}
+ if (caughtOnCancel != null) {
+ causes.add(caughtOnCancel);
+ }
if (caughtOnStart != null) {
causes.add(caughtOnStart);
}
@@ -180,9 +159,7 @@
* @see
com.google.gwt.place.shared.PlaceChangeRequestEvent.Handler#onPlaceChangeRequest(PlaceChangeRequestEvent)
*/
public void onPlaceChangeRequest(PlaceChangeRequestEvent event) {
- if (!currentActivity.equals(NULL_ACTIVITY)) {
- event.setWarning(currentActivity.mayStop());
- }
+ event.setWarning(currentActivity.mayStop());
}
/**
@@ -203,6 +180,41 @@
updateHandlers(willBeActive);
}
}
+
+ public Throwable tryStart() {
+ Throwable caughtOnStart = null;
+ try {
+ /* Wrap the actual display with a per-call instance
+ * that protects the display from canceled or stopped activities,
and which
+ * maintains our startingNext state.
+ */
+ currentActivity.start(new ProtectedDisplay(currentActivity),
+ stopperedEventBus);
+ } catch (Throwable t) {
+ caughtOnStart = t;
+ }
+ return caughtOnStart;
+ }
+
+ public Throwable tryStopOrCancel(boolean stop) {
+ Throwable caughtOnStop = null;
+ try {
+ if (stop) {
+ currentActivity.onStop();
+ } else {
+ currentActivity.onCancel();
+ }
+ } catch (Throwable t) {
+ caughtOnStop = t;
+ } finally {
+ /*
+ * Kill off the handlers again in case it was naughty and added new
ones
+ * during onstop or oncancel
+ */
+ stopperedEventBus.removeHandlers();
+ }
+ return caughtOnStop;
+ }
private Activity getNextActivity(PlaceChangeEvent event) {
if (display == null) {
=======================================
---
/trunk/user/test/com/google/gwt/activity/shared/ActivityManagerTest.java
Mon Apr 18 16:25:25 2011
+++
/trunk/user/test/com/google/gwt/activity/shared/ActivityManagerTest.java
Fri Jun 3 08:57:30 2011
@@ -305,6 +305,53 @@
assertEquals(0, eventBus.getCount(PlaceChangeRequestEvent.TYPE));
}
+ public void testExceptionsOnStartAndCancel() {
+ activity1 = new AsyncActivity(null) {
+ @Override
+ public void start(AcceptsOneWidget panel, EventBus eventBus) {
+ super.start(panel, eventBus);
+ bus.addHandler(Event.TYPE, new Handler());
+ }
+ @Override
+ public void onCancel() {
+ super.onCancel();
+ bus.addHandler(Event.TYPE, new Handler());
+ throw new UnsupportedOperationException("Exception on cancel");
+ }
+ };
+
+ activity2 = new SyncActivity(null) {
+ @Override
+ public void start(AcceptsOneWidget panel, EventBus eventBus) {
+ super.start(panel, eventBus);
+ throw new UnsupportedOperationException("Exception on start");
+ }
+ };
+
+ manager.setDisplay(realDisplay);
+
+ try {
+ PlaceChangeEvent event = new PlaceChangeEvent(place1);
+ eventBus.fireEvent(event);
+ assertEquals(1, eventBus.getCount(Event.TYPE));
+
+ event = new PlaceChangeEvent(place2);
+ eventBus.fireEvent(event);
+
+ fail("Expected exception");
+ } catch (UmbrellaException e) {
+ // EventBus throws this one
+ assertEquals(1, e.getCauses().size());
+ // And this is the one thrown by ActivityManager
+ UmbrellaException nested = (UmbrellaException) e.getCause();
+ assertEquals(2, nested.getCauses().size());
+ }
+
+ assertTrue(activity1.canceled);
+ assertNotNull(activity2.display);
+ assertEquals(0, eventBus.getCount(Event.TYPE));
+ }
+
public void testExceptionsOnStopAndStart() {
activity1 = new SyncActivity(null) {
@Override
@@ -316,7 +363,7 @@
public void onStop() {
super.onStop();
bus.addHandler(Event.TYPE, new Handler());
- throw new UnsupportedOperationException("Auto-generated method
stub");
+ throw new UnsupportedOperationException("Exception on stop");
}
};
@@ -324,7 +371,7 @@
@Override
public void start(AcceptsOneWidget panel, EventBus eventBus) {
super.start(panel, eventBus);
- throw new UnsupportedOperationException("Auto-generated method
stub");
+ throw new UnsupportedOperationException("Exception on start");
}
};
@@ -340,9 +387,9 @@
fail("Expected exception");
} catch (UmbrellaException e) {
- // HandlerManager throws this one
+ // EventBus throws this one
assertEquals(1, e.getCauses().size());
-
+ // And this is the one thrown by ActivityManager
UmbrellaException nested = (UmbrellaException) e.getCause();
assertEquals(2, nested.getCauses().size());
}
--
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