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Make $JAVA_HOME easily changable in Ubuntu [closed]
In Ubuntu, I'd like to switch my JAVA_HOME environment variable back and forth between Java 5 and 6.
8 Answers
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Is there a REAL performance difference between INT and VARCHAR primary keys?
...AR as the primary key for reference lists (think US States, Country Codes) and a coworker won't budge on the INT AUTO_INCREMENT as a primary key for all tables.
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Why would adding a method add an ambiguous call, if it wouldn't be involved in the ambiguity
...s, you have found a bug in overload resolution. The bug reproduces in C# 4 and 5; it does not reproduce in the "Roslyn" version of the semantic analyzer. I've informed the C# 5 test team, and hopefully we can get this investigated and resolved before the final release. (As always, no promises.)
A c...
How to validate IP address in Python? [duplicate]
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Hmm, seems to accept things like "4" and "192.168" and silently pads the rest with zeros. Technically valid, I'm sure, but not quite what I expected.
– krupan
Nov 25 '08 at 23:58
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Why should I use version control? [closed]
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Have you ever:
Made a change to code, realised it was a mistake and wanted to revert back?
Lost code or had a backup that was too old?
Had to maintain multiple versions of a product?
Wanted to see the difference between two (or more) versions of your code?
Wanted to prove that a particula...
The JPA hashCode() / equals() dilemma
There have been some discussions here about JPA entities and which hashCode() / equals() implementation should be used for JPA entity classes. Most (if not all) of them depend on Hibernate, but I'd like to discuss them JPA-implementation-neutrally (I am using EclipseLink, by the way).
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How to generate a random int in C?
Is there a function to generate a random int number in C? Or will I have to use a third party library?
27 Answers
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Difference in System. exit(0) , System.exit(-1), System.exit(1 ) in Java
...er programming languages where it's useful to know if something went wrong and what went wrong.
Exit code is
0 when execution went fine;
1, -1, whatever != 0 when some error occurred, you can use different values for different kind of errors.
If I'm correct exit codes used to be just positive n...
Is there any way to create a blank solution (.sln) file first and then add projects?
...ys annoyed me because (to my knowledge) you cannot create a solution first and then add new/existing projects to it. The only way I know how to create a solution is to create a project and specify the solution name for it.
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Evaluate expression given as a string
...ied. For example, if you have a pre-defined variable name equal to "David" and you reassign using eval(parse(text = "name") == "Alexander", you will get an error because eval & parse do not return an R expression that can be evaluated.
– Crt
Aug 1 '16 at 22...