I seem to be running into an odd problem. When using my GWT application in a local environment, everything works as it should. The problem comes in after I compile and deploy my application. When I go through my project workflow and click on a certain link to switch into a new panel, I get the following error (from my console in Chrome):
Uncaught com.google.gwt.event.shared.UmbrellaException: One or more exceptions
caught, see full set in UmbrellaException#getCauses (anonymous function)
This error is thrown by one of the cache file generated by GWT at compile time. But this never happens on the locally deployed program (deployed from Eclipse, "Run as Web Application"). Has anyone ever run into this issue or can provide any direction for a fix?
Thank you! :)
I had the same problem just now. Works locally, fails with the mentioned Javascript console error, nothing in server logs.
Turns out that client Java code (which is complied to Javascript) had try/catch block which worked when executed in Java, but failed silently when compiled to Javascript. I'm still not sure what was the exact nature of the problem, but try removing try/catch blocks.
(It seems that in my case, table.getWidget() call was failing and throwing exception.)
I had the same problem, i think interpretation of try catch is not the same than in Java... after gwt compilation, when you are in catch case, the execution failed. If you open firebug, you can see point of errors into JS.
I had the same problem, it worked in development mode. Then, after I compiled I would get an error. To fix, I had to get rid of:
try{
//some code
} catch(NullPointerException ex){
//more code
}
Instead I did:
if(variable != null){
//some code
} else {
//more code
}
After that it worked perfectly.
Related
I'm getting NG0100 error (Expression changed) in my console. Is there any way I can catch this error in my code and print it in the console via my code?
I tried try catch block but it doesn't seem to be working.
try{
//error generating code
}
catch(e){
console.log(e.message)
}
Thanks!
Actually, catch a NG0100 won't help that much. It's not a blocking error, it's just a big warning to tell yout that your code is unsafe and some expressions change at a point of the component genereation where it shouldn't.
It is supported by Angular DoubleCheck wich is a system that check your template binded attributes to make sure your code is stable and predictable. NG0100 means your expression has changed between these two checks.
It is just a warning because this DoubleCheck only exists in devmode (aka ng serve or ng build --configuration developement).
Best you can do is find why and where this happens in your code, to avoid it.
The informations given can't let us know, but you can watch this video from Angular official documentation that explains most common reasons of NG0100
I have the following problem:
I have recently started working on another PC with WebStorm 2016.1.3.
The code that was written before that on the previous PC works fine. But writing on this one, screws everything up.
Whatever variable I initialize, I get error:
com.google.gson.JsonParseException expected BEGIN_ARRAY was BEGIN_OBJECT at line 1 column 1217.
Here is debug snapshot:
You can see how the first array is okay, but the rest is just screwed. Really weird problem, and I suspect the IDE. Anyone had that issue?
There was a problem with the cache of the browser and the IDE. It fixed itself after restart and cache kill.
I'm building a small application with ReactJS and sometimes find it difficult to debug it.
Every time I make some Javascript error, like missing let/var in front of new variable, missing require for a component that I later use, my application just stops working (the code does not execute beyond the line where the error is), but I'm not getting any errors in browser's console. It seems as if some ReactJS code was intercepting errors, maybe handling them some custom way. Is there anything like that in ReactJS? How can I see errors in the console?
I'm using gulp/gulp-connect/browserify set to run the application.
Let me know if you need any additional data or code samples, I'll update the question.
If you know that an error is thrown but swallowed by some other code, you can enable in your browser's debugger to pause execution when an exception is thrown, even if it is caught somewhere:
Note however that libraries sometimes deliberately trigger exceptions while testing whether the browser supports certain features. You'd have to step over those.
Usage of React Hot Loader which is a Webpack plugin should solve most of the problems you have in a development process. It's easy to integrate into existing project and has quite a few examples how to put all the things together.
As a result:
your code changes would be pushed to the browser
in case of the error you will have meaningful stack trace in the browser console.
I'm guessing that the incorrect JS syntax is causing your gulp process to fail which would result in your application not being bundled/deployed in the browser at all.
It seems like there should be errors in your system console (where gulp is running) - as opposed to your browser console. Possibly your gulp process crashes when this happens too. If there are no errors in your console, you may have to listen for them. This post has an example of how to log errors from browserify:
gulp.task('browserify', function(){
var b = browserify();
b.add('./main.js');
return b.bundle()
.on('error', function(err){
console.log(err.message); //
this.end();
})
.pipe(source('main.out.js'))
.pipe(gulp.dest('./dist'));
});
Probably the best solution is to run your code through jshint before browserify so that you aren't trying to browserify syntactically invalid code.
Caveat: not a current gulp user
I suffered from the similar problem with this like missing let/var, require, and other trivial mistakes inside of the react context.
In my case, the cause is the mistake of Promise statement. Promise seems to suppress any exceptions that occur after it is called.
I could resolve the problem by handling exception like below.
var Promise = require('es6-promise').Promise;
var promise = new Promise(...)
promise
.then(function(data){...})
.catch(function(e) {
console.error(e.stack)
}
react-slingshot is a starter kit and it shows error at compile time and shows stack trace on the browser. It also has testing set up.
I have a long CasperJS script. When I run it I get:
phantomjs file.js
SyntaxError: Parse error
Is there a way to get some more information about the error.
At least a line number? or any hint at all?
Try run the file.js with node, so for your example:
node file.js
It's not possible to determine this in PhantomJS itself. The documentation on phantom.onError says:
This is the closest it gets to having a global error handler in PhantomJS
And this doesn't catch the syntax error. If you try to run it with the --debug=true option, you will see a lot of debug messages, but the final error has still the same amount of information.
Another thing that I tried was to use a second PhantomJS script which reads the original script and tries to eval it. The phantom.onError event is triggered in this case, but the trace argument is empty.
The good thing is that PhantomJS/CasperJS scripts are just JavaScript, so you can paste them to http://jslint.com/ or run a dedicated jslinter on them to see where the problem lies. There are some options that you have to mark on the site or otherwise you will get a lot of errors:
add phantom to the global variables box,
enable node.js mode and
tolerate "everything" (or those things that you actually want to tolerate)
I spent a whole 8hrs on this to find a trick for this problem. The trick is to run "phantomjs" and type 'require "path_to_js_file"'. I used 2.1.1 version of phantomjs. Likely 2.2 also works.
Then there will be a stack trace that shows which line is the offender. You won't see this in testem output.
In my case, if you define a property twice for an object, it will work for chrome, firefox etc, but not phantomjs. Lint might help but there are >5K lint errors for the project I work on and it is practically impossible to see what's wrong. Also the particular problem is likely hidden under the same bucket of "javascript strict mode violation". Nodejs didn't complain this either.
I'm getting the following error in IE 6:
Line: 454
Char: 13
Error: Invalid Argument
Code: 0
URL: xxxxx/Iframe1.aspx
and I can't for the life of me find what's causing this.
This only happens in a situation where I have a main page that has several IFrames, and it only happens when I have one particular IFrame (the one pointed to by the URL in the error message), and that IFrame is invisible at the time of loading.
I've narrowed it up to there, but I still can't find anything more specific...
The IFrame in question doesn't have 454 lines in its HTML, nor do any of the JS files referred by it.
I tried attaching VS to iexplore.exe as a debugger, and it breaks when the error occurs, but then tells me "There is no source code available for the current location"...
Any suggestions on how I can go about chasing this one?
UPDATE: I found this problem through brute-force, basically, commenting everything out and uncommenting randomly...
But the question still stands: what is the rational way to find where the error is, when IE reports the wrong line number / file?
IE's Javascript engine is disgusting when it comes to debugging. You can try enabling script debugging in the Advanced Options, and then if you have Visual Studio installed it will jump to the place of error... if you're lucky. Other times you don't get anything, especially if the code was eval()'ed.
Another thing about these line numbers is that it doesn't reflect which file the error is happening in. I've had cases where the line number was actually correct, but it was in a linked .js file, not the main file.
Try using the Microsoft Script Debugger or DebugBar (http://www.debugbar.com) which may give you some better IE6 debugging tools. They always help me with IE6.
Also, does this happen in any newer versions of IE or just in IE6?
It's virtually impossible to debug this without a live example, but one thing that often causes an "Invalid Argument" error in Internet Explorer is trying to set an incorrect value for a style property.
So something like:
document.getElementById("foo").style.borderWidth = bar + "px";
when "bar" has the value null, or undefined, or is the string "grandma", will cause it, as "grandmapx" isn't a valid value for the borderWidth style property.
IE9 has a browser mode.
Open up Developer Tools, then select the version you want to emulate in the console, reload the page with errors, and the console will show you line numbers and the correct file where the error is.
I run into this problem a lot too, and I've also resorted to commenting everything out until I find the problem. One thing that I find to be useful is to add a try/catch block to every javascript method. Sometimes I add an alert to tell what method the error came from. Still tedious, but easier than trial and error commenting. And if you add them every time you write a new method it saves a lot of time in the event errors like those occur.
function TestMethod()
{
try
{
//whatever
}
catch (ex)
{
ShowError(ex.description);
//alert("TestMethod");
}
}
A note to other readers: I recently had this "Invalid argument." error reported in IE7-9 and eventually found that it was down to the way I was using setTimeout/setInterval.
This is wrong, in IE:
var Thing = {};
Thing.myFunc = function() { ... };
setTimeout(Thing.myFunc, 1000);
Instead, wrap the callback in an anonymous function like so:
var Thing = {};
Thing.myFunc = function() { ... };
setTimeout(function() { Thing.myFunc(); }, 1000);
and no more "invalid argument" errors.
Another possibility:
I do a lot of dev between two computers, at home and at work, so I often email myself or download pages from the server to work on. Recently I realised that Vista has a habit of unilaterally applying blocks to certain files when they are downloaded in certain ways, without notifying me that it is doing this.
The result is that, for example, an HTML page wants to access the .js file in its header, but it doesn't have permission to access local files. In this case, it doesn't matter what you write in the .js file, the browser will never even read it, and an irksome Line: 0 error will result.
So before you comb your code for an error, check your HTML page's properties, and see if it hasn't been blocked by the OS....
Like NickFitz pointed out, styling was an issue with my code.
document.getElementById('sums<%= event.id %>').style.border='1px solid #3b3b3b;'
I removed the border style and my IE issues were gone.