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What is reflection and why is it useful?
... say you have an object of an unknown type in Java, and you would like to call a 'doSomething' method on it if one exists. Java's static typing system isn't really designed to support this unless the object conforms to a known interface, but using reflection, your code can look at the object and fin...
What is Persistence Context?
...erence/en/html/architecture.html
In Java EE, a persistence context is normally accessed via an EntityManager.
http://docs.oracle.com/javaee/6/api/javax/persistence/EntityManager.html
The various states an entity can have and the transitions between these are described below:
http://docs.jboss.or...
How much size “Null” value takes in SQL Server
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The smallest addressable unit of memory in most computer systems is one byte (typically 8 bits). So in reality, a bit takes a byte. Great answer Mark: +1.
– JohnB
Sep 16 '10 at 22:23
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How can I install pip on Windows?
pip is a replacement for easy_install . But should I install pip using easy_install on Windows? Is there a better way?
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Fatal error: Class 'ZipArchive' not found in
I have a problem that I install 'Archive_Zip 0.1.1' on Linux server, but when I try to run the script to create the zip file it gives the fatal error
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Should Github be used as a CDN for javascript libraries? [closed]
.... The last one means less total work for everybody, so it's clearly a win all around, and is more likely the more often we (developers) rely on the CDNs to serve our javascript.
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Why use make over a shell script?
...t would be a lot more work (explicitly checking the last-modified dates on all the files, etc.) The only obvious alternative with a shell script is to rebuild everything every time. For tiny projects this is a perfectly reasonable approach, but for a big project a complete rebuild could easily take ...
Convert NSArray to NSString in Objective-C
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Won't this accomplish the same thing as calling [array description]?
– TechZen
Dec 1 '09 at 20:55
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Single Line Nested For Loops
...ertools.product, which returns an iterable yielding tuples of values from all the iterables you pass it. That is, itertools.product(A, B) yields all values of the form (a, b), where the a values come from A and the b values come from B. For example:
import itertools
A = [50, 60, 70]
B = [0.1, 0.2...
How can I write a regex which matches non greedy? [duplicate]
...eedy ? works perfectly fine. It's just that you need to select dot matches all option in the regex engines (regexpal, the engine you used, also has this option) you are testing with. This is because, regex engines generally don't match line breaks when you use .. You need to tell them explicitly tha...