I have an activity with a fragment which contains a MapView. The MapView uses an OfflineTileProvider, with tiles downloaded using the CacheManager. When entering and exiting the activity repeatedly, the app will sometimes freeze. Sometimes it happens after revisiting the activity once or twice, and sometimes it takes many more times(20 or more) before it freezes.
Every time I enter the activity there are two kinds of exceptions being thrown, the first one being:
Error loading tile
java.lang.IllegalStateException: Cannot perform this operation because the connection pool has been closed.
at android.database.sqlite.SQLiteConnectionPool.throwIfClosedLocked(SQLiteConnectionPool.java:962)
at android.database.sqlite.SQLiteConnectionPool.waitForConnection(SQLiteConnectionPool.java:677)
at android.database.sqlite.SQLiteConnectionPool.acquireConnection(SQLiteConnectionPool.java:348)
at android.database.sqlite.SQLiteSession.acquireConnection(SQLiteSession.java:894)
at android.database.sqlite.SQLiteSession.executeForCursorWindow(SQLiteSession.java:834)
at android.database.sqlite.SQLiteQuery.fillWindow(SQLiteQuery.java:62)
at android.database.sqlite.SQLiteCursor.fillWindow(SQLiteCursor.java:145)
at android.database.sqlite.SQLiteCursor.getCount(SQLiteCursor.java:134)
at org.osmdroid.tileprovider.modules.MapTileSqlCacheProvider$TileLoader.loadTile(MapTileSqlCacheProvider.java:209)
at org.osmdroid.tileprovider.modules.MapTileModuleProviderBase$TileLoader.run(MapTileModuleProviderBase.java:297)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1133)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:607)
at java.lang.Thread.run(Thread.java:760)
and the second one:
Unable to store cached tile from Mapnik /0/0/0 db is null
java.lang.NullPointerException: Attempt to invoke virtual method 'int android.database.sqlite.SQLiteDatabase.delete(java.lang.String, java.lang.String, java.lang.String[])' on a null object reference
at org.osmdroid.tileprovider.modules.SqlTileWriter.saveFile(SqlTileWriter.java:175)
at org.osmdroid.tileprovider.modules.MapTileDownloader$TileLoader.loadTile(MapTileDownloader.java:251)
at org.osmdroid.tileprovider.modules.MapTileModuleProviderBase$TileLoader.run(MapTileModuleProviderBase.java:297)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1133)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:607)
at java.lang.Thread.run(Thread.java:760)
Have anyone else had similar issues, or know what to do?
That's a fun one. Looks like a lifecycle/concurrency problem. It's possible that the old instances of the map fragment are still alive. You may be able to work around the issue by forcing android to execute now:
From osmdroid test/instrumentation package
fm.beginTransaction().replace(org.osmdroid.R.id.samples_container, basefrag, ExtraSamplesActivity.SAMPLES_FRAGMENT_TAG)
.addToBackStack(ExtraSamplesActivity.SAMPLES_FRAGMENT_TAG).commit();
fm.executePendingTransactions();
Basically, it forces the fragment transaction to happen immediately which should force the android lifecycle stuff to happen.
The other possibility is that you have a static reference to the map or something that's holding on to the map reference or your offline tile provider instance. Are any of those possible?
Edit: I just tested map in a fragment by loading and unloading the map a bunch of times and could not reproduce it. Are you programmatically creating the map or are you using xml layout?
Related
So I'm getting this error every so often when running the exact same test.
StaleElementReferenceException: Message: stale element reference: element is not attached to the page document
(Session info: chrome=69.0.3497.100)
(Driver info: chromedriver=2.41.578706 (5f725d1b4f0a4acbf5259df887244095596231db),platform=Mac OS X 10.12.6 x86_64)
The only problem is that it seems to happen inconsistently to different areas of the code. It's when trying to access DOM elements, like a search field, of my ReactJS page. I'm running this through ROBOT Automation Framework, using a mix of the SeleniumLibrary and a custom library.
I've read that it's simply as it sounds, the xPath as become outdated on the DOM, but that doesn't help me figure out why it's an inconsistent error happening almost anywhere at any point.
EDIT: It seems to be happening in this:
def filter_modality(self, filter):
filter_value = '//span[#title="{}"]//parent::li'.format(filter)
self.selib.click_element(filter_locator)
self.selib.wait_until_page_contains_element('//*[#class="multi-selector-options open"]')
self.selib.wait_until_element_is_visible(filter_value)
self.selib.click_element(filter_value )
self.selib.wait_until_page_contains_element('//div...[#class="option selector-item active"]',
error=("Could not select filter: {}".format(filter_value )))
#I get the stale element message from or after executing this click_element
self.selib.click_element(filter_locator)
self.selib.wait_until_page_does_not_contain_element('//*[#class="multi-selector-options open"]',
error="Filter dropdown did not disappear after selection")
The exception comes when SE has found an element, but shortly afterwards something (a JS function) has changed it - removed from/rearranged it in the DOM, or changed its attributes significantly, so it's no longer tracked as the same element.
This comes for the fact that SE builds an internal cache of the DOM, which may become desynchronized from the actual one; thus the name "stale" - the el. is cached in some state, but its actual form is now different.
The issue is that common, that there is a specific SO tag for it - https://stackoverflow.com/questions/tagged/staleelementreferenceexception (I myself was surprised from this).
The common solutions are:
sleep for some seconds before an event you know will cause the issue
re-get an element before its usage (if you store a reference to it in a WebElement object, not really the case with robotframework)
have a rertry mechanism on working with an element that you know may cause the execution
swallow the exception and move along (I've done it in a few places, where the element was just a confirmation an operation was executed - it has been shown/found by SE once, afterwards I don't care is it changed in the DOM)
I'm building an ember app, and I keep running into the same problem where I make a call to the store, but the function keeps compiling before the store has retrieved the data from the backend. Specifically I'm having the problem with a findRecord. I've implemented it both ways:
var admin = this.store.findRecord('admin', 1);
console.log(admin.get('season'));
console.log('Are we here?');
and
this.store.findRecord('admin', 1).then(function(admin) {
console.log(admin.get('season'));
});
console.log('Are we here?');
In both cases, the Are we here? is logged BEFORE the season. Obviously the console logs are just for the example, and it creates an actual problem with what I'm trying to get done. Does anybody know a simple fix for this delay?
Thanks.
Of course it is. It's an asynchronous behavior. It takes some time to solve promise which is returned from findRecord(), thus the consequence is:
this.store.findRecord(); //synchronous
console.log('we are here'); //synchronous
in the meantime a promise returned from findRecord() gets resolved (asynchronous behavior)
console.log(admin.get('season'));
An asynchronous call will not stop your code from progressing, that´s the purpose of it. Else it would block UI updates and user interaction while loading data.
I have a list of objects. They are JPA "Location" entities.
List<Location> locations;
I have a stateless EJB which loops thru the list and persists each one.
public void createLocations() {
List<Locations> locations = getListOfJPAManagedLocationEntities(); // I'm leaving out the details of this because it has nothing to do with the issue
for(Location location : locations) {
em.persist(location);
}
}
The code works fine. I do not have any problems.
However, the issue is: I want this to be an all-or-none transaction. Currently, each time thru the for loop, the persist() method will insert a new row into the database. Suppose I have 100 location objects and the 54th object has something wrong with it and an exception is thrown. There will be 53 records inserted into the database. What I want is: all of them must succeed before any of them succeed.
I'm using the latest & greatest version of Java EE6, EJB 3.x., and JPA 2. My persistence.xml uses JTA.
<persistence-unit name="myPersistenceUnit" transaction-type="JTA">
And I like having JTA.
I do not want to stop using JTA.
90% of the time JTA does exactly what I want it to do. But in this case, I doesn't seem to.
My understanding of JTA must be inaccurate because I always thought the beginning and end of the EJB method marked the boundaries of the JTA transaction (assume only one method is in-play as I've shown above). By my logic, the transaction would not end until the for-loop is done and the method returns, and then at that point the records are persisted.
I'm using the JTDS driver for SqlServer 2008. Perhaps the database doesn't want to insert a record without immediately committing it. The entity id is defined like this:
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
I've checked the spec., and it is not proper to call the various "UserTransaction" or "getTransaction()" methods in a JTA environment.
So what can I do?
Thanks.
If you use JTA and container managed transactions the default behavior for an session EJB method call is to run in a transaction (is like annotating it with #TransactionAttribute(TransactionAttributeType.REQUIRED). That means that your code already runs in a transaction and will do what you expect: if an exception occurs at row 54 all previous inserted rows will be rolled-back. You can go ahead and test it by throwing yourself an exception at some point in the loop. Note that if you throw a checked exception declared by your method you can specify what the container should do when that exception occurs. You need to annotate the exception class with #ApplicationException (rollback=true).
if there was a duplicate entry while looping then it will continue without problems and when compiler reaches this line em.flush(); after the loop then it will throw an exception and rollback the transaction.
I'm using JBoss. Set your datasource in your standalone.xml or domain.xml to have
<datasource jta="true" ...>
Seems obvious, but I obviously set it wrong a long time ago and forgot about it.
We have a set of Coldfusion applications that all extended various parts of an application base. I'll provide a bit of code and then explain the issues we are having and see if anyone can shed light on the best way to trouble shoot this:
In our "OnRequestStart" in the app.cfc we have the following line to initiate a user:
if(!structKeyExists(SESSION, 'user'))
SESSION.user = CreateObject("component","cfcs.ds_user");
Then in the ds_user.cfc we call it like so:
component extends="cas.cas_user" displayname="basic_user"{
The application and all its parts run just like they should. However, in a seeming random manner after a while, the application will crash and I have to restart ColdFusion Service to get it running again. The error I get is:
Could not find the ColdFusion component or interface cas.cas_user.
So, for whatever reason after a while, my application decides it cannot find the path to the parent component. The mapping for that cfc is in the application.cfc at the top as so:
THIS.mappings["/cas"] = "#ReplaceNoCase(currpath,ListToArray(THIS.name,'_')[1],'cas30')#assets\cfcs\";
I want to be sure to say this, the application works perfectly as designed for a random amount of time and then it cannot find the parent component and will not find it again until I restart the ColdFusion Service on the server.
I figure this is somehow a memory leak or something, but I have no idea where to start looking to troubleshoot the issue. We have 6 or so other applications that are extended in the same way and work fine and never crash, but this one does.
EDIT: To be more clear on the mappings. Our applications are located:
root.com/app1
root.com/app2
We created mappings to grab cfcs from app2 while in app1 using the method above. The method, while I believe sort of strange, does work in all of our applications.
EDIT: The correct mappings that display for a while are:
/cfcs - D:\www\app1\assets\cfcs
/templates - D:\www\app1\assets\templates
/cas - D:\www\app2\assets\cfcs
/common - D:\www\app3\assets\common_elements
However once the Application goes in "crashed mode", the dump reveals the mappings are as follows:
/cfcs - D:\www\app1\assets\cfcs
/templates - D:\www\app1\assets\templates
/cas - D:\www\app1\assets\cfcs
/common - D:\www\app1\assets\common_elements
And here is how those mappings are defined at the start of the Application.cfc:
currpath = GetDirectoryFromPath(GetCurrentTemplatePath());
THIS.mappings["/templates"] = "#currpath#assets\templates";
THIS.mappings["/cfcs"] = "#currpath#assets\cfcs";
THIS.mappings["/common"] = "#ReplaceNoCase(currpath,ListToArray(THIS.name,'_')[1],'gum')#assets\common_elements\";
THIS.mappings["/cas"] = "#ReplaceNoCase(currpath,ListToArray(THIS.name,'_')[1],'cas30')#assets\cfcs\";
THIS.name = digisign_CAAAFACBFDFFE or
name_var = (arrayLen(meta_array) >= 2) ? meta_array[arrayLen(meta_array) - 1] & '_' : 'root_';
THIS.name = name_var & right(reReplace(hash(getCurrentTemplatePath()), "[^a-zA-Z]","","all"), 64 - len(name_var));
Where could it be failing. It seems the replace statement isn't working and therefore the appname in the path is not being changed from app1 to app2 when setting the mappings. is it possible this is related to this error we are currently working through: http://forums.adobe.com/message/4657868#4657868 We have yet to apply the Update 4 patch on production. However this problem we believe was happening before CF10. And while we have this issue, it only cropped up recently. This application in question has been crashing like this for a long time.
EDIT:
1. I guess when I say "crash" I mean the application gets into a state, where it will not declare the mappings correctly until I restart Coldfusion. I assume the error in our code causes the crash.
2.This is usually where the issue occurs, when doing this check of the SESSION.user var. I believe it has happened as well, it decides it cannot find our datasource. This is rare.
3. At first I thought yes, but actually no, not that many. Throughout our apps we have several names for common mappings. cas common cfcs templates etc. However D:\www\cas is where the application domain.com/cas30 is located. However a legacy version of that app is located at domain.com/cas. The mapping /cas should go to D:\www\cas30\assets\cfcs and works.
4.We have a dev setup and this never happens. (I assumed it was a load issue which is why it doesn't happen on dev). However, our dev environment is structred as so:
D:\www\deva\app1
D:\www\deva\app2
D:\www\devb\app1
D:\www\devb\app2
What we do (which I think is stupid) is we have a file located not in the same dir as the current app. This file is called application_base.cfc. All of the application.cfcs in the other applications extend from this application_base.cfc. They are not extended from other Application.cfc files. (hope that makes sense) In application_base is a init, onrequeststart, and an onerror. I'll post the App.cfc below. Also some setting are read from XML files both in the application base (to determine environment stuff) and at the application level. However we thought that might be causing the issue so the previous developer removed the xml file at the application level.
6.Yes. I'll post the app.cfc and the appbase.cfc so you can view both.
By reinitialize you mean call onapplicationstart or something. Not that I know of.
A few applications we have do:
currpath = GetDirectoryFromPath(GetCurrentTemplatePath());
app_path = ListToArray(currpath,'\');
THIS.name = app_path[ArrayLen(app_path)];
This one does:
meta_array = ListToArray(GetMetaData(this).name,'.');
name_var = (arrayLen(meta_array) >= 2) ? meta_array[arrayLen(meta_array) - 1] & '_' : 'root_';
THIS.name = name_var & right(reReplace(hash(getCurrentTemplatePath()), "[^a-zA-Z]","","all"), 64 - len(name_var));
A few others do this as well. Not sure if it was two different developers or something, but that is the way it is.
Once the app fails, it fails until I restart coldfusion. The app requires login from the domain.com/app page, so (not saying it cant change from request to request) but the request location is always the same where it's failing.
God I wish it wasn't this complex. I recently pulled our current CMS off of alot of this crazy stuff, but we have 7 or 8 applications that are so intertwined with each other and designed to work in dev/prod environments with different paths, its sometimes hard to tell what I can remove and what I can't.
I thought I tried dumping the applicationname from our error handler, but I thought it didn't work unless passed in. I passed through the mappings so I could see them which is how I know digisign is not changing to cas30 like it should in "crash" mode.
I think all the dynamic mappings were so the original developer could just use the same app.cfc template without changing anything. He liked to do stuff like var a = (b) ? (a-c) ? a-f+b : (a+b) ? d : d; : a; h; crap with no comments so it sometimes hard to just read the damn code let alone debug it.
EDIT
I feel like this issue and stackoverflow.com/q/14300915/1229594 issue may be related. I've posted some more details here as well: forums.adobe.com/message/5022377#5022377
First things first: why are you initialising session-oriented stuff in onREQUESTStart()? If you inited that in onSessionStart(), you'd not need to check for its existence every request, which - whilst trivial - is unnecessary overhead, and is simply the wrong code in the wrong place.
Secondly... you quote your error, but don't say where it's happening. Is it happening in that line in onRequestStart()?
If so, do me a favour: put a try/catch around it, and within that write the value of this.mappings to a log file, as well as the value of currPath. How is the value of that variable being derived, btw?
That said, I think if you just put that session.user init code in the right place, it'll solve your problem.
NB: frame this problem as almost certainly not a memory leak (ie: ColdFusion's fault), but your code doing something you did not anticipate (so... err... your fault ;-). This will help focus better on finding the problem. I'm not having a go at you, but "where is my code wrong" is a better approach than "it's probably something else". And more likely to be correct ;-)
Oh... and what version of CF are you on?
Take a look at this and see if it's relevant to your problem.
https://github.com/Mach-II/Mach-II-Framework/wiki/Application-Specific-Mapping-Workaround
If not, then it could have something to do with application specific mappings of the same name, on the same CF server, with those applications having different application names.
Some questions:
Are you assuming the crash is being caused by the code error, or that the code error is occurring because of the crash?
Is the instantiation of the session user the only line of code that you see these path errors?
Do you have any physical directories in your app that have the same name as the mapping names?
Does this occur in any other environments (dev/test)? Is this a clustered environment?
Are there multiple Application.cfc files extending this same Application.cfc?
Is there any code that is directly calling Application.cfc methods?
Are there any bits of code that cause the application to reinitialize itself?
What is determining the meta_array that is being used to derive the application name?
A few observations:
It seems to me that the application name is getting changed or that some other application is overwriting with the same name. This doesn't seem far-fetched as there's an awful lot of dynamic naming going on here. Starting with the application name, it's dependent on the current template's physical location, which could be different from request to request, depending on how the app routes requests. If the current template varies, the application name will vary, and cause the other app-specific mappings to change, which would cause a cascading effect to all the other mappings that use the app name to determine the physical location of those mappings.
Which begs the question: Why is all this dynamic evaluation of the application name and mapping locations even necessary? Can it be simplified or hard-coded? Can you instead use a server mapping? If it doesn't have to be this complex, simplifying it to its barest essentials will help troubleshooting and may clear up the issue entirely.
Finally, can you verify that the application name during normal operation is the same application name being referenced when the errors are occurring?
If they are different, then something is causing the application to execute within a different context (see my initial questions above for clues). A sudden change in the application name would invalidate any existing sessions and force the session user instantiation code to re-run. And because the user component paths are based in part on the application name, the paths may no longer be correct.
But if the application names are the same between normal operation and crash mode, then most likely the currpath variable is being affected by some part of the application being executed in a different physical path than expected. Since currpath is directly used in determining the rest of the mappings, that could certainly explain why an unexpected path could cause the component to go missing.
Because there are so many variables going into deriving these names, you would be well served to log those variables during normal operation and during crash mode. You'll want to see
GetCurrentTemplatePath()
GetDirectoryFromPath(GetCurrentTemplatePath())
THIS.name
meta_array
THIS.mappings
I suspect you'll find something significantly different in these variables when operating normally and when the crash/errors are occurring, and that difference should lead you closer to the answer.
I'm writing a little clojure pub/sub interface. It's very barebones, only two methods that will actually be used: do-pub and sub-listen. sub-listen takes a string (a sub name) and do-pub takes two strings (a sub name and a value).
I'm still fairly new at clojure and am having some trouble coming up with a workable way to do this. My first thought (and indeed my first implementation) uses a single agent which holds a hash:
{ subname (promise1 promise2 etc) }
When a thread wants to sub it conj's a promise object to the list associated with the sub it wants, then immediately tries to de-reference that promise (therefore blocking).
When a pub happens it goes through every item in the list for the sub and delivers the value to that item (the promise). It then dissoc's that subname from the map and returns it to the agent.
In this way I got a simple pub sub implementation working. However, the problem comes when someone subs, doesn't receive a pub for a certain amount of time, then gets killed due to timeout. In this scenario there will be a worthless promise in the agent that doesn't need to be, and moreover this will be a source of a memory leak if that sub never gets pub'd.
Does anyone have any thoughts on how to solve this? Or if there is a better way to do what I'm trying to do overall (I'm trying to avoid using any external pre-cooked pubsub libraries, this is a pet project not a work one)?
You can do something like this:
Create an atom
publish function will update the atom value by the passed in value to the function
Subscribers can use add-watch on the atom to be notified of when the atom value changes i.e due to call to publish function
Use remove-watch to remove the subscription.
This way you will have a very basic pub-sub system.
I have marked Ankur's answer as the solution but I wanted to expand on it a bit. What I ended up doing is having a central atom that all client threads do an add-watch on. When a pub is done the atom's value is changed to a vector containing the name of the sub and the value being pub'd.
The function the clients pass to add-watch is a partial function which looks like
(partial (fn [prom sub key ref _old new] ...) sub prom)
where prom is a promise previously generated. The client then blocks while waiting on that promise. The partial function checks if the sub in new is the same as sub, if so it removes the watch and delivers on the promise with the value from new.