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How does push notification technology work on Android?
...ts confirmed the client is polling along a tcp connection right ? do you know how often it polls for data ? is it every 5 seconds for example. or is it fast like a heartbeat ?
– j2emanue
Apr 10 '19 at 8:58
...
Why is there no SortedList in Java?
... takes a Comparator<T>.
Alternatively, you can use Multisets (also known as Bags), that is a Set that allows duplicate elements, instead and there are third-party implementations of them. Most notably from the Guava libraries there is a TreeMultiset, that works a lot like the TreeSet.
2. Sor...
Convert HTML to PDF in .NET
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Update: I would now recommend PupeteerSharp over wkhtmltopdf.
Try wkhtmtopdf. It is the best tool I have found so far.
For .NET, you may use this small library to easily invoke wkhtmtopdf command line utility.
...
Check if pull needed in Git
...they're equal, the branches are the same. If they're unequal, you want to know which is ahead of the other. Using git merge-base master origin/master will tell you the common ancestor of both branches, and if they haven't diverged this will be the same as one or the other. If you get three different...
Search for executable files using find command
...ric questions, it is sufficient to use the POSIX-compliant -perm primary (known as a test in GNU find terminology).
-perm allows you to test for any file permissions, not just executability.
Permissions are specified as either octal or symbolic modes. Octal modes are octal numbers (e.g., 111), whe...
When to use extern in C++
... variables in a header, so that each source file that includes the header knows about it, but you only need to “define” it once in one of your source files.
To clarify, using extern int x; tells the compiler that an object of type int called x exists somewhere. It's not the compilers job to kno...
HTTPURLConnection Doesn't Follow Redirect from HTTP to HTTPS
...od in the source.) There is no way to disable this check.
Even though we know it mirrors HTTP, from the HTTP protocol point of view, HTTPS is just some other, completely different, unknown protocol. It would be unsafe to follow the redirect without user approval.
For example, suppose the applicati...
What is a C++ delegate?
...l a sad testimoney on how C++ evolves.
Only rarely is it pointed out, that now over 3 C++ standard revisions, delegates were not properly addressed. (Or the lack of language features which allow for straightforward delegate implementations.)
With the way C++11 lambda functions are defined by the sta...
How to jump to a particular line in a huge text file?
...n't jump ahead without reading in the file at least once, since you don't know where the line breaks are. You could do something like:
# Read in the file once and build a list of line offsets
line_offset = []
offset = 0
for line in file:
line_offset.append(offset)
offset += len(line)
file....
Java: Subpackage visibility?
....out.println(classInAInB.getData());
// Works: getDataAsBytes() is now accessible
System.out.println(Arrays.toString(classInAInB.getDataAsBytes()));
}
}
Note that this only works for protected members, which are visible to extending classes (inheritance), and not package-privat...