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How do you cast a List of supertypes to a List of subtypes?
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Simply casting to List<TestB> almost works; but it doesn't work because you can't cast a generic type of one parameter to another. However, you can cast through an intermediate wildcard type and it will be allowed (since you can cast to a...
The Use of Multiple JFrames: Good or Bad Practice? [closed]
I'm developing an application which displays images, and plays sounds from a database. I'm trying to decide whether or not to use a separate JFrame to add images to the database from the GUI.
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Patterns for handling batch operations in REST web services?
What proven design patterns exist for batch operations on resources within a REST style web service?
8 Answers
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What is a practical use for a closure in JavaScript?
... privatefunction();
}
}
})();
As you can see there, a is now an object, with a method publicfunction ( a.publicfunction() ) which calls privatefunction, which only exists inside the closure. You can NOT call privatefunction directly (i.e. a.privatefunction() ), just publicfunct...
Invalid argument supplied for foreach()
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Personally I find this to be the most clean - not sure if it's the most efficient, mind!
if (is_array($values) || is_object($values))
{
foreach ($values as $value)
{
...
}
}
The reason for my preference is it doesn't alloc...
What exactly does git's “rebase --preserve-merges” do (and why?)
Git's documentation for the rebase command is quite brief:
2 Answers
2
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Default behavior of “git push” without a branch specified
...ion:
push.default
Defines the action git push should take if no refspec is given on the command line, no refspec is configured in the remote, and no refspec is implied by any of the options given on the command line. Possible values are:
nothing: do not push anything
matching: push all matching...
Merge, update, and pull Git branches without using checkouts
... Amber's answer will also work in fast-forward cases, using git fetch in this way instead is a little safer than just force-moving the branch reference, since git fetch will automatically prevent accidental non-fast-forwards as long as you don't use + in the refspec.
The Long Answer
You cannot merge...
What does 'synchronized' mean?
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The synchronized keyword is all about different threads reading and writing to the same variables, objects and resources. This is not a trivial topic in Java, but here is a quote from Sun:
synchronized methods enable a simple
strategy for prev...
IllegalArgumentException or NullPointerException for a null parameter? [closed]
I have a simple setter method for a property and null is not appropriate for this particular property. I have always been torn in this situation: should I throw an IllegalArgumentException , or a NullPointerException ? From the javadocs, both seem appropriate. Is there some kind of an understood...