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Co-variant array conversion from x to y may cause run-time exception
...js[0] = new Foo(); // again legal, with runtime exception
In C#, you are allowed to reference an array of objects (in your case, LinkLabels) as an array of a base type (in this case, as an array of Controls). It is also compile time legal to assign another object that is a Control to the array. Th...
Get selected subcommand with argparse
...s:
>>> parser = argparse.ArgumentParser()
>>> parser.add_argument('-g', '--global')
>>> subparsers = parser.add_subparsers(dest="subparser_name") # this line changed
>>> foo_parser = subparsers.add_parser('foo')
>>> foo_parser.add_argument('-c', '--count...
Simplest way to serve static data from outside the application server in a Java web application
...s from where this command is been invoked. So if Tomcat is for example installed on C: then the /path/to/files would actually point to C:\path\to\files.
If the files are all located outside the webapp, and you want to have Tomcat's DefaultServlet to handle them, then all you basically need to do in ...
A type for Date only in C# - why is there no Date type?
...
Allow me to add an update to this classic question:
Jon Skeet's Noda Time library is now quite mature, and has a date-only type called LocalDate. (Local in this case just means local to someone, not necessarily local to th...
Python Threading String Arguments
...t list
processThread.start()
If you notice, from the stack trace: self.__target(*self.__args, **self.__kwargs)
The *self.__args turns your string into a list of characters, passing them to the processLine
function. If you pass it a one element list, it will pass that element as the first argum...
Why can't I use the 'await' operator within the body of a lock statement?
The await keyword in C# (.NET Async CTP) is not allowed from within a lock statement.
8 Answers
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Database sharding vs partitioning
...databases. Sharding is one specific type of partitioning, part of what is called horizontal partitioning.
Here you replicate the schema across (typically) multiple instances or servers, using some kind of logic or identifier to know which instance or server to look for the data. An identifier of th...
Data access object (DAO) in Java
I was going through a document and I came across a term called DAO . I found out that it is a Data Access Object. Can someone please explain me what this actually is?
...
How to use the CancellationToken property?
...t points where you can stop executing safely across loop body, and loop usually have some logical condition to exit (iterate over all items in collection etc.). So I believe it's better not to mix that conditions as they have different intention.
Cautionary note about avoiding CancellationToken.Thr...
Cast Object to Generic Type for returning
...> T convertInstanceOfObject(java.lang.Object);
Code:
0: aload_0
1: areturn
2: astore_1
3: aconst_null
4: areturn
Exception table:
from to target type
0 1 2 Class java/lang/ClassCastException
public static void main(java...