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Accessing Android List with Nativescript

The Short
I am trying to create a List<ScanFilter> in JavaScript by accessing Android API, as shown below:
var scanFilterList = new java.util.List<android.bluetooth.le.ScanFilter>;
However, JavaScript gives me a SyntaxError due to an unexpected token, which I presume is because of the angle brackets. Any assistance in overcoming this problem and creating a List<ScanFilter> would be greatly appreciated!!
The Long
I want to periodically run BluetoothLE scans in my NativeScript application (only worrying about the android side for the moment), even while the screen is turned off. To my understanding this would be possible, as stated in the documentation:
For unfiltered scans, scanning is stopped on screen off to save power. Scanning is resumed when screen is turned on again. To avoid this, do filtered scanning by using proper ScanFilter.
Source
I am attempting to create a ScanFilter to be used as a parameter for startScan() when it is called. However, when I try to create a new List as shown below:
var scanFilterList = new java.util.List<android.bluetooth.le.ScanFilter>;
I get a SyntaxError due to an unexpected token. I am assuming this is because the angle-brackets aren't recognized by JavaScript and cause problems.
How can I bypass this problem and successfully create a List<ScanFilter> variable in JavaScript for use.

Debugging JavaScript in client

I'm facing an issue while debugging my application. Following is the architecture:
Server: Java (Servlet)
Client: React+D3
Problem: Whenever, I change some react or d3 code and if an error occurs then it just shows me that some react (or d3) error has occurred but never tells me which function the error occurred (as seen in snapshot). Now, I know that simply debugging it by having the information like variable name and searching where I defined that variable. However, situation becomes tough when I use same object multiple times (say window) and had made several changes in the code. In this case, a specific line number where the error occured can be handy and quick. Let me know if I'm missing some basics about debugging such applications?
EDIT1:
1. In the snapshot, http://localhost:8080/..../Server Server is the main servlet application, kind of launchpad, which triggers several other react-based js files.
2. The mentioned ReferenceError is inside a function updateWindow() but the console never mentions this (and that's my problem).
PS: I'm using Eclipse tomcat on server-side

I think there's no straight forward solution to this problem. So, I'll post the method that worked for me with few additional points:
Problem: It doesn't gives a nice error trace like standard Java application, probably because it mixes with JavaScript code.
At every line of the error trace, line:column specifies the error line. I used this as a reference and started manual debugging from where my application launches i.e. Server.java and look where I defined the createChart() in the JS file and drill-down until I found the referenced variable.
In case of ReactJS' error (an error after resolving reference issue), I debugged it with normal react.js (not minified version react.min.js) so that it shows me exact line of error. Minified version is cluttered and is useless while debugging.
PS: If someone has better answer I'll edit this in future.

How to load Component and its Classes in my website

I am trying to over ride one the notification popups of browser using the following code:
var branch = Components.classes["#mozilla.org/preferences-service;1"].getService(Components.interfaces.nsIPrefBranch);
But in Mozilla Firefox, I get the error Component.classes is undefined.
And in Chrome Browser, I get the error Component is undefined.
Well I have realised I need to include something in my website. But I am unable to find exactly what is required.
Please anybody help. I googled about it a lot, but I have never used this thing before(the Classes) and I am unable to search what will help me out. i dont even have any idea that what will be the tags for this thing. I have never used Component or its classes
My website is in ZF2.

Components Object is non-standard feature. See https://developer.mozilla.org/en/docs/Components_object.
It also says
Warning: This object is only intended for code running with chrome
privileges. Exposing the object to regular web code was a mistake.

Code Sign Javascript to use 'new ActiveXObject()' / 'GetObject()'

I've got a javascript file that uses
excel = GetObject("", "Excel.Application");
to hook a current running instance of excel, however it requires me to drop my security settings super low. How do I go about code-signing a javascript file to at least cause a security prompt instead of just failing? Google-ing keeps getting me results for signing custom activex controls, .dlls, and .exes but all I need is the built-in function approved.
On a related note
http://msdn.microsoft.com/en-us/library/7tf9xwsc%28v=vs.94%29.aspx
"The GetObject function is not supported in Internet Explorer 9 standards mode or later."
What is the proper method for accessing a currently running application in IE9 then?

There is no way to do that; there's no "code signing" mechanism for JavaScript.

Output the rendered contents of a page on a JavaScript error

I'm having problems with getting decent JavaScript error invormation in a Production environment.
When I'm developing I can just attach a debugger and (usually) fix the problem.
When I get the same error in a production environment however at best I see is an error report that looks like this:
Error: Object doesn't support this property or method
Url: SomePage
Line: 42
Char: 13
Which doesn't help me very much - I can't see the rendered page and so I have no idea what line 42 looks like.
Is there any way for me to log the entire rendered page contents whenever an error like this occurs? (So line 42 of the output is the line where the error occured)
While I'm at it, are there any other techniques that I can use to help with getting useful error information from JavaScript (without need to break into the debugger) - failing that is there any way that I can structure my JavaScript slightly differently to help getting decent debug information?
I'm predominantly interested in IE - this is the browser that tends to cause me most problems.

I don't think you'll be able to get the exact original HTML source of the page back in all pages and all browsers.
Regarding debugging, you could use a logging library such as log4javascript (disclaimer: I wrote it) and intersperse logging calls in your code. log4javascript enables you to send logging messages back to the server via Ajax.

Unfortunately, IE has by default the most utterly useless error reporting. The script and line number reported in the error are essentially guaranteed to be absolutely wrong. You can, however, install the IE developer tool bar (for IE7 and older, it's built into IE8) from Microsoft, which can help track down the error source.