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Collections.emptyList() vs. new instance
...ntly.
In addition, emptyList() might not create a new object with each call.
Implementations of this method need not create a separate List object for each call. Using this method is likely to have comparable cost to using the like-named field. (Unlike this method, the field does not provide ...
Copy multiple files in Python
How to copy all the files present in one directory to another directory using Python.
I have the source path and the destination path as string.
...
Pull to refresh UITableView without UITableViewController
...reshControl()
refreshControl.addTarget(self, action: #selector(refresh(_:)), for: .valueChanged)
if #available(iOS 10.0, *) {
tableView.refreshControl = refreshControl
} else {
tableView.backgroundView = refreshControl
}
}
@objc func refresh(_ refreshControl: UIRefr...
How to free memory in Java?
...
Java uses managed memory, so the only way you can allocate memory is by using the new operator, and the only way you can deallocate memory is by relying on the garbage collector.
This memory management whitepaper (PDF) may help explain what's going on.
You can also call Sy...
How do I return rows with a specific value first?
...
That actually works in any SQL database (and is a much cleaner solution than the accepted answer in my opinion)
– a_horse_with_no_name
Sep 24 '13 at 20:49
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How to change the color of an svg element?
I want to use this technique http://css-tricks.com/svg-fallbacks/ and change the svg color but so far I haven't been able to do so. I put this in the css but my image is always black, no matter what. My code:
...
Equivalent of *Nix 'which' command in PowerShell?
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Is there any way to have the path all the time without to type '| Format-Table Path, Name' ?
– Guillaume
Jan 11 '13 at 8:18
11
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Is an index needed for a primary key in SQLite?
...x be explicitly created for it as well? SQLite does not appear to automatically create an index for a primary key column, but perhaps it indexes it anyway, given its purpose? (I will be searching on that column all the time).
...
“sending 'const NSString *' to parameter of type 'NSString *' discards qualifiers” warning
I have Constants NSString, that I want to call like:
3 Answers
3
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What version of javac built my jar?
...ersion the class has been compiled FOR, not what version compiled it. Java allows you to compile code so that they're compatible with earlier versions of Java. However, this only applies to byte code and format. It will happily compile code that references JDK 6 libraries into a JDK 5 format, for ex...