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What causes imported Maven project in Eclipse to use Java 1.5 instead of Java 1.6 by default and how
I imported a Maven project and it used Java 1.5 even though I have 1.6 configured as my Eclipse default Preferences->Java->Installed JREs .
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mongodb count num of distinct values per field/key
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MongoDB has a distinct command which returns an array of distinct values for a field; you can check the length of the array for a count.
There is a shell db.collection.distinct() helper as well:
> db.countries.distinct('country');
[ "Spain", "Engl...
Java resource as file
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ClassLoader.getResourceAsStream and Class.getResourceAsStream are definitely the way to go for loading the resource data. However, I don't believe there's any way of "listing" the contents of an element of the classpath.
In some cases this may be simply im...
How can I create a unique constraint on my column (SQL Server 2008 R2)?
I have SQL Server 2008 R2 and I want to set a unique column.
4 Answers
4
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Declaring an enum within a class
...is declared within the Car class in order to limit the scope of the enum and to try not to "pollute" the global namespace.
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Using Mockito's generic “any()” method
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Since Java 8 you can use the argument-less any method and the type argument will get inferred by the compiler:
verify(bar).doStuff(any());
Explanation
The new thing in Java 8 is that the target type of an expression will be used to infer type parameters of its sub-expressi...
Objective-C for Windows
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Expanding on the two previous answers, if you just want Objective-C but not any of the Cocoa frameworks, then gcc will work on any platform. You can use it through Cygwin or get MinGW. However, if you want the Cocoa frameworks, ...
When would you use a WeakHashMap or a WeakReference?
...mplementation of so I'm trying to figure out what the use case for them is and how the implementation would work. When have you needed to use a WeakHashMap or WeakReference and how was it used?
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What are the relationships between Any, AnyVal, AnyRef, Object and how do they map when used in Java
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I'll disagree with Chris's answer in one regard. The classes Any, AnyRef and AnyVal are classes. But they don't appear as classes in bytecode, because of intrinsic limitations of the JVM.
This arises out of the fact that not everything in Java is an object. In addition to objects, there are primi...
What platforms have something other than 8-bit char?
Every now and then, someone on SO points out that char (aka 'byte') isn't necessarily 8 bits .
12 Answers
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