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In log4j, does checking isDebugEnabled before logging improve performance?
...using Log4J in my application for logging. Previously I was using debug call like:
16 Answers
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How to get all properties values of a JavaScript Object (without knowing the keys)?
... for you:
for (var key in obj) {
if (Object.prototype.hasOwnProperty.call(obj, key)) {
var val = obj[key];
// use val
}
}
The nested if makes sure that you don't enumerate over properties in the prototype chain of the object (which is the behaviour you almost certainly wan...
How to import a class from default package
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Wow I really don't know java at all. That was a great help. Guess I'll have to move my class into a package...
– anhoppe
Jan 20 '16 at 20:14
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capturing self strongly in this block is likely to lead to a retain cycle
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Good answer, but I take small issue with you saying: “you can't refer to self or properties on self from within a block that will be strongly retained by self.” This is not strictly true. Please see my answer below. Better to say, “you must take...
Android Studio suddenly cannot resolve symbols
...e imports and AS seems to be telling me it can't find android.support.v4 all of a sudden (offering me the option to remove the unused imports). ( android.support.v7 seems to be fine though).
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Mocking Extension Methods with Moq
...es, there are other (non-free) mocking frameworks that use .NET's profiler API to mock objects and so can replace any calls. The two I know are Telerik's JustMock and TypeMock Isolator.
– Marcel Gosselin
Aug 24 '11 at 4:34
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What is the difference between C++ and Visual C++? [duplicate]
...979 at Bell Labs as an enhancement to the C programming language and originally named "C with Classes". It was renamed to C++ in 1983.
C++ is widely used in the software industry. Some of its application domains include systems software, application software, device drivers, embedded software, high...
How to reshape data from long to wide format
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The reshape comments and similar argument names aren't all that helpful. However, I have found that for long to wide, you need to provide data = your data.frame, idvar = the variable that identifies your groups, v.names = the variables that will become multiple columns in wide f...
Generate a random double in a range
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This is generally correct, but beware of its limits. If you do double rangeMax= Double.MAX_VALUE; and double rangeMin= -rangeMax; you will always get an infinite value in return. You might want to check for Double.valueOf(rangeMax-range...
How can I use a local image as the base image with a dockerfile?
...ockerfile.
I just realised that I've been using FROM with indexed images all along.
4 Answers
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