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What is the difference between mutex and critical section?
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Mutexes can be shared between processes, but always result in a system call to the kernel which has some overhead.
Critical sections can only be used within one process, but have the advantage that they only switch to kernel mode in the case of contention - Uncontended acquires, which should be ...
Covariance, Invariance and Contravariance explained in plain English?
... say it is used to decide whether a method is overwritten or overloaded.
All of the above.
At heart, these terms describe how the subtype relation is affected by type transformations. That is, if A and B are types, f is a type transformation, and ≤ the subtype relation (i.e. A ≤ B means that ...
newline in [duplicate]
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This should really be voted up higher. No need to get a jQuery plugin. This plus some extra styling and positioning should be a fantastic option for anybody. I'm going to use it right now, working for a gigantor company that you all know.
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Does Swift have access modifiers?
...Enable an entity to be used outside the defining module (target). You typically use open or public access when specifying the public interface to a framework.
However, open access applies only to classes and class members, and it differs from public access as follows:
public classes and class mem...
Add floating point value to android resources/values
...ue = outValue.getFloat();
I know that this is confusing (you'd expect call like getResources().getDimension(R.dimen.text_line_spacing)), but Android dimensions have special treatment and pure "float" number is not valid dimension.
Additionally, there is small "hack" to put float number into d...
Why do some claim that Java's implementation of generics is bad?
I've occasionally heard that with generics, Java didn't get it right. (nearest reference, here )
13 Answers
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How to auto-remove trailing whitespace in Eclipse?
...to Code organizing tab -> check Remove trailing whitespace -> select All lines.
Removing whitespace only from the lines I changed:
Preferences -> Java -> Editor -> Save Actions -> check "Perform the selected actions on save -> check Format source code -> select Format edi...
How can I perform a culture-sensitive “starts-with” operation from the middle of a string?
... mapping.
You would need to know the length of the substring that was actually matched. But Compare, IndexOf ..etc
throw that information away. It could be possible with regular expressions but the implementation doesn't do full case folding and so doesn't match
ß to ss/SS in case-insensitive mode...
How to Implement DOM Data Binding in JavaScript
...ake this work, your object needs to implement the eventListener interface. All that's needed to accomplish this is to give the object a handleEvent() method.
That's where the inheritance comes in.
MyCtor.prototype.handleEvent = function(event) {
switch (event.type) {
case "change": th...
How to check visibility of software keyboard in Android?
...ve your activity's root view a known ID, say @+id/activityRoot, hook a GlobalLayoutListener into the ViewTreeObserver, and from there calculate the size diff between your activity's view root and the window size:
final View activityRootView = findViewById(R.id.activityRoot);
activityRootView.getVie...