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What's quicker and better to determine if an array key exists in PHP?
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isset() is faster, but it's not the same as array_key_exists().
array_key_exists() purely checks if the key exists, even if the value is NULL.
Whereas
isset() will return false if the key exist and value is NULL.
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How to force garbage collection in Java?
Is it possible to force garbage collection in Java, even if it is tricky to do? I know about System.gc(); and Runtime.gc(); but they only suggest to do GC. How can I force GC?
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How to use “raise” keyword in Python [duplicate]
I have read the official definition of "raise", but I still don't quite understand what it does.
6 Answers
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How do I tokenize a string in C++?
Java has a convenient split method:
35 Answers
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When should we call System.exit in Java
In Java, What is the difference with or without System.exit(0) in following code?
10 Answers
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What is the purpose of Serialization in Java?
I have read quite a number of articles on Serialization and how it is so nice and great but none of the arguments were convincing enough. I am wondering if someone can really tell me what is it that we can really achieve by serializing a class?
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Why does integer overflow on x86 with GCC cause an infinite loop?
The following code goes into an infinite loop on GCC:
6 Answers
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How do I pass variables and data from PHP to JavaScript?
I have a variable in PHP, and I need its value in my JavaScript code. How can I get my variable from PHP to JavaScript?
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How to deal with a slow SecureRandom generator?
...you use SecureRandom . Unfortunately, SecureRandom can be very slow. If it uses /dev/random on Linux, it can block waiting for sufficient entropy to build up. How do you avoid the performance penalty?
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Why are variables “i” and “j” used for counters?
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It comes ultimately from mathematics: the summation notation traditionally uses i for the first index, j for the second, and so on. Example (from http://en.wikipedia.org/wiki/Summation):
It's also used that way for co...