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Pick a random value from an enum?

...esult of values() because each call copies an array. Also, don't create a Random every time. Keep one. Other than that what you're doing is fine. So: public enum Letter { A, B, C, //... private static final List<Letter> VALUES = Collections.unmodifiableList(Arrays.asList(values...
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Can javax.persistence.Query.getResultList() return null?

And if so, under what circumstances? 7 Answers 7 ...
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Which is preferred: Nullable.HasValue or Nullable != null?

...eal difference. Just do whichever is more readable/makes more sense to you and your colleagues. share | improve this answer | follow | ...
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How to measure time taken by a function to execute

...is required to import the performance class Using console.time: (non-standard) (living standard) console.time('someFunction') someFunction() // Whatever is timed goes between the two "console.time" console.timeEnd('someFunction') Note: The string being pass to the time() and timeEnd() metho...
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Why does .NET foreach loop throw NullRefException when collection is null?

...the answer might be obvious to some people, it is not obvious to everyone, and providing the hint that looking at the IL will tell you what the compiler is doing, helps people fish for themselves in the future. – Robaticus May 10 '17 at 23:36 ...
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Check if a temporary table exists and delete if it exists before creating a temporary table

I am using the following code to check if the temporary table exists and drop the table if it exists before creating again. It works fine as long as I don't change the columns. If I add a column later, it will give an error saying "invalid column". Please let me know what I am doing wrong. ...
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Where is the warnings screen option in Android Studio?

I want to see warnings of my code in Android Studio, But i am unable to find the option to display warnings view. In case of eclipse we can see the warnings in the "Problems" view. ...
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Pipe to/from the clipboard in Bash script

... has a utility that lets you talk to it. In the case of X, there's xclip (and others). xclip -selection c will send data to the clipboard that works with Ctrl + C, Ctrl + V in most applications. If you're on Mac OS X, there's pbcopy. e.g cat example.txt | pbcopy If you're in Linux terminal mode (...
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How to quickly and conveniently create a one element arraylist [duplicate]

...ariable size List If it needs vary in size you can construct an ArrayList and the fixed-sizeList like return new ArrayList<String>(Arrays.asList(s)); and (in Java 7+) you can use the diamond operator <> to make it return new ArrayList<>(Arrays.asList(s)); Single Element Lis...
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How do I write a Firefox Addon? [closed]

...ction are about getting started (that includes Adam's link). The newsgroup and the irc channel in the Community section are the official discussion boards. Mozilla is very complex, so any kind of API guide would be overwhelming and hard to write. So your best bet is to check the code snippets page ...