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Why can't static methods be abstract in Java?
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Because "abstract" means: "Implements no functionality", and "static" means: "There is functionality even if you don't have an object instance". And that's a logical contradiction.
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What happens to a declared, uninitialized variable in C? Does it have a value?
If in C I write:
10 Answers
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What is the difference between typeof and instanceof and when should one be used vs. the other?
...} instanceof Object; // true
typeof {}; // object
And the last one is a little bit tricky:
typeof null; // object
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Class does not implement its superclass's required members
...want to be NSCoding-compatible is to do something like this:"
required init(coder: NSCoder) {
fatalError("NSCoding not supported")
}
If you know you don't want to be NSCoding compliant, this is an option. I've taken this approach with a lot of my SpriteKit code, as I know I won't be loading it...
Is Java really slow?
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Modern Java is one of the fastest languages, even though it is still a memory hog. Java had a reputation for being slow because it used to take a long time for the VM to start up.
If you still think Java is slow, see the benchmarks game results. Tightly optimized code written in ...
When to use Mockito.verify()?
I write jUnit test cases for 3 purposes:
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What are rvalues, lvalues, xvalues, glvalues, and prvalues?
In C++03, an expression is either an rvalue or an lvalue .
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what is the difference between XSD and WSDL
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XSD defines a schema which is a definition of how an XML document can be structured. You can use it to check that a given XML document is valid and follows the rules you've laid out in the schema.
WSDL is a XML document that describes a web service. It shows w...
What is null in Java?
...pression is not null and the reference could be cast to the ReferenceType without raising a ClassCastException. Otherwise the result is false.
This means that for any type E and R, for any E o, where o == null, o instanceof R is always false.
What set does 'null' belong to?
JLS 4.1 The Kin...
Why is SCTP not much used/known
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Indeed, SCTP is used mostly in the telecom area. Traditionally, telecom switches use SS7 (Signaling System No. 7) to interconnect different entities in the telecom network. For example - the telecom provider's subscriber data base(HLR), with a switch (MSC), the subscriber is co...