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What is this date format? 2011-08-12T20:17:46.384Z
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@MarounMaroun: Basically we want those literal characters. It may not be necessary for T (I can't remember how SimpleDateFormat handles unknown specifiers) but for Z we want it to be the character 'Z' rather than "a UTC offset value" (e.g. "00")...
remove legend title in ggplot
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This will remove all legend titles. For more local control, the guide = guide_legend() command works. To remove the fill legend title, but to keep the color legend title, e.g. scale_fill_brewer(palette = "Dark2", guide = guide_legend(title = ...
How do you increase the max number of concurrent connections in Apache?
...ts 200
MinSpareThreads 25
MaxSpareThreads 75
ThreadsPerChild 25
First of all, whenever an apache is started, it will start 2 child processes which is determined by StartServers parameter. Then each process will start 25 threads determined by ThreadsPerChild parameter so this means 2 process can se...
How to reset Jenkins security settings from the command line?
Is there a way to reset all (or just disable the security settings) from the command line without a user/password as I have managed to completely lock myself out of Jenkins ?
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How to gracefully handle the SIGKILL signal in Java
...uts down in response to two kinds of events:
The program exits normally, when the last non-daemon thread exits or when the exit (equivalently, System.exit) method is invoked, or
The virtual machine is terminated in response to a user interrupt, such as typing ^C, or a system-wide event, su...
How does Java handle integer underflows and overflows and how would you check for it?
... long or maybe java.math.BigInteger. The last one doesn't overflow, practically, the available JVM memory is the limit.
If you happen to be on Java8 already, then you can make use of the new Math#addExact() and Math#subtractExact() methods which will throw an ArithmeticException on overflow.
pub...
What's invokedynamic and how do I use it?
I keep hearing about all the new cool features that are being added to the JVM and one of those cool features is invokedynamic. I would like to know what it is and how does it make reflective programming in Java easier or better?
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Why are Perl 5's function prototypes bad?
...nd to expect prototypes to provide a mechanism for checking that function calls are correct: that is, that they have the right number and type of arguments. Perl's prototypes are not well-suited for this task. It's the misuse that's bad. Perl's prototypes have a singular and very different purpose:
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How does '20 seconds' work in Scala?
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There are a few things going on.
First, Scala allows dots and parens to be omitted from many method calls, so 20 seconds is equivalent to 20.seconds()*.
Second, an "implicit conversion" is applied. Since 20 is an Int and Int has no seconds method, the compiler searches ...
PHP parse/syntax errors; and how to solve them
...as T_STRING explains which symbol the parser/tokenizer couldn't process finally. This isn't necessarily the cause of the syntax mistake, however.
It's important to look into previous code lines as well. Often syntax errors are just mishaps that happened earlier. The error line number is just where ...