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Predicate in Java
... someone guide me to any tutorial or conceptual explanation of Predicate and its implementation in Java?
4 Answers
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What is the difference between mutex and critical section?
... between the two of them. On my system for 1,000,000 uncontended acquires and releases, a mutex takes over one second. A critical section takes ~50 ms for 1,000,000 acquires.
Here's the test code, I ran this and got similar results if mutex is first or second, so we aren't seeing any other effect...
Convert float to double without losing precision
I have a primitive float and I need as a primitive double. Simply casting the float to double gives me weird extra precision. For example:
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Javascript !instanceof If Statement
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Enclose in parentheses and negate on the outside.
if(!(obj instanceof Array)) {
//...
}
In this case, the order of precedence is important (https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Operators/Operator_Precedence). The ! o...
Authentication versus Authorization
...ontext of web applications? I see the abbreviation "auth" a lot. Does it stand for auth -entication or auth -orization? Or is it both?
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'Static readonly' vs. 'const'
I've read around about const and static readonly fields. We have some classes which contain only constant values. They are used for various things around in our system. So I am wondering if my observation is correct:
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Python unittest - opposite of assertRaises?
...r test must exit with a failure condition, not an error one. On the other hand, if in running the same code you would raise a KeyError, that would be an error, not a failure. In python - differently than some other languages - Exceptions are routinely used for control flow, this is why we have the e...
Correct Bash and shell script variable capitalization
I run across many shell scripts with variables in all caps, and I've always thought that there is a severe misunderstanding with that. My understanding is that, by convention (and perhaps by necessity long ago), environment variables are in all-caps.
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How can sbt pull dependency artifacts from git?
I've heard (and I know I've seen examples too, if only I can remember where) that sbt can obtain dependencies from a git repo.
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Error while installing json gem 'mkmf.rb can't find header files for ruby'
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For Xcode 11 on macOS 10.14, this can happen even after installing Xcode and installing command-line tools and accepting the license with
sudo xcode-select --install
sudo xcodebuild -license accept
The issue is that Xcode 11 ships the macOS 10.15 SDK which includes headers for ruby2.6, but no...