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Map.clear() vs new Map : Which one will be better? [duplicate]
...stance, which is backed with new array. So, garbage collector should clear all the key and values from the previous map, and clear the reference to itself. So O(n) algorithm is executed anyway, but in the garbage collector thread. For 1000 records you won't see any difference.
BUT. The performance ...
Select n random rows from SQL Server table
...the key scan of values plus the join cost, which on a large table with a small percentage selection should be reasonable.
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How can I get a list of build targets in Ant?
... the available built targets without having to search through the file manually. Does ant have a command for this - something like ant show-targets - that will make it list all the targets in the build file?
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Disable scrolling in webview?
...mething I haven't been able to figure out on Android is how to programmatically prevent scrolling in a WebView ?
14 Answer...
Coroutine vs Continuation vs Generator
.... As @zvolkov mentioned, they're functions/objects that can be repeatedly called without returning, but when called will return (yield) a value and then suspend their execution. When they're called again, they will start up from where they last suspended execution and do their thing again.
A genera...
Clearing using jQuery
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Easy: you wrap a <form> around the element, call reset on the form, then remove the form using .unwrap(). Unlike the .clone() solutions otherwise in this thread, you end up with the same element at the end (including custom properties that were set on it).
Tested and wo...
private final static attribute vs private final attribute
...riable);
That makes the behaviour much more obvious. Modern IDEs will usually suggest changing the second listing into the third.
There is no reason to have an inline declaration initializing the value like the following, as each instance will have its own NUMBER but always with the same value (i...
Change app language programmatically in Android
Is it possible to change the language of an app programmatically while still using Android resources?
35 Answers
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Is there a CSS not equals selector?
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In CSS3, you can use the :not() filter, but not all browsers fully support CSS3 yet, so be sure you know what you're doing which is now
supported by all major browsers (and has been for quite some time; this is an old answer...).
Example:
<input type="text" value="wi...
What is the difference between const_iterator and non-const iterator in the C++ STL?
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const_iterators don't allow you to change the values that they point to, regular iterators do.
As with all things in C++, always prefer const, unless there's a good reason to use regular iterators (i.e. you want to use the fact that they're not c...