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Should a retrieval method return 'null' or throw an exception when it can't produce the return value
...uld mean that there was a problem.
If the value can be missing or present and both are valid for the application logic then return a null.
More important: What do you do other places in the code? Consistency is important.
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Why is an MD5 hash created by Python different from one created using echo and md5sum in the shell?
A Python MD5 hash is different than the one created by the md5sum command on the shell. Why?
1 Answer
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What is thread contention?
...he most obvious example of contention is on a lock. If thread A has a lock and thread B wants to acquire that same lock, thread B will have to wait until thread A releases the lock.
Now, this is platform-specific, but the thread may experience slowdowns even if it never has to wait for the other th...
Why does String.valueOf(null) throw a NullPointerException?
...ring.valueOf(Object)
String.valueOf(char[])
Java Specification Language mandates that in these kind of cases, the most specific overload is chosen:
JLS 15.12.2.5 Choosing the Most Specific Method
If more than one member method is both accessible and applicable to a method invocation, it is n...
How do I create a unique constraint that also allows nulls?
...er below.
Prior to SQL Server 2008
You cannot create a UNIQUE constraint and allow NULLs. You need set a default value of NEWID().
Update the existing values to NEWID() where NULL before creating the UNIQUE constraint.
s...
Should a RESTful 'PUT' operation return something
...st specific URI for the new resource returned in the Location header field and any other relevant URIs and metadata of the resource echoed in the response body. (RFC 2616 Section 10.2.2)
HTTP status code 409 Conflict for a PUT that is unsuccessful due
to a 3rd-party modification, with a list of diff...
How do I run IDEA IntelliJ on Mac OS X with JDK 7?
I use Mac OS X 10.8.2, and use JDK 7. Now I downloaded the latest version of IDEA IntelliJ, 11. But it doesn't seem to start without JDK 6. Is there any workaround?
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What's the difference between a proxy server and a reverse proxy server? [closed]
What is the difference between a proxy server and a reverse proxy server?
21 Answers
2...
Measuring execution time of a function in C++
... When I use this function, on first run it gave me 118440535 microseconds and on second run of the same function it gave me 83221031 microseconds. Shouldn't the two time measurements be equal when I am measuring the duration of that function only ?
– Xara
Mar ...
Why do we not have a virtual constructor in C++?
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Hear it from the horse's mouth. :)
From Bjarne Stroustrup's C++ Style and Technique FAQ Why don't we have virtual constructors?
A virtual call is a mechanism to get work done given partial
information. In particular, "virtual" allows us to call a function
knowing only any interfaces and...