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Connection pooling options with JDBC: DBCP vs C3P0
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Would really love get a troubleshoot using BoneCP as a Tomcat Datasource. The main problem I had with this was that it required BoneCP Classes in tomcat's lib dir, as well as the log4j and google classes. Doing this made the connecti...
Cannot set some HTTP headers when using System.Net.WebRequest
...ht to the last section of the answer.
If you want to know better, read it all, and i hope you'll enjoy...
I countered this problem too today, and what i discovered today is that:
the above answers are true, as:
1.1 it's telling you that the header you are trying to add already exist and you s...
Exif manipulation library for python [closed]
...mation from Jpeg and Tiff files which include it. This information is typically included in images created using digital imaging devices such as digital cameras, digital film scanners, etc.
However, it looks like pyexif hasn't been updated in quite while. They recommend if theirs isn't doing the ...
How can I lock a file using java (if possible)
...fy that second process that the file is already opened? Does this automatically make the second process get an exception if the file is open (which solves my problem) or do I have to explicitly open it in the first process with some sort of flag or argument?
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Comma in C/C++ macro
...his is also a problem for square brackets and braces, even though those usually occur as balanced pairs.) You can enclose the macro argument in parentheses:
FOO((std::map<int, int>), map_var);
The problem is then that the parameter remains parenthesized inside the macro expansion, which pr...
Twitter Bootstrap 3: how to use media queries?
...electors used in BS4. There is no "lowest" setting in BS4 because "extra small" is the default. I.e. you would first code the XS size and then have these media overrides afterwards.
@media(min-width:576px){}
@media(min-width:768px){}
@media(min-width:992px){}
@media(min-width:1200px){}
Update 201...
Event system in Python
...r methods', which is a
simple implementation of the Observer pattern.
Basically, the handler methods (callables) are stored in an array and are each called when the event 'fires'.
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The disadvantage of Observer event systems is that you can only register the handlers on the actual Ev...
How to make a valid Windows filename from an arbitrary string?
...: Bar" that I want to use as a filename, but on Windows the ":" char isn't allowed in a filename.
14 Answers
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MySQL, Check if a column exists in a table with SQL
...pecific column, and if not — create it. Otherwise do nothing. This is really an easy procedure in any enterprise-class database, yet MySQL seems to be an exception.
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Find an item in List by LINQ?
Here I have a simple example to find an item in a list of strings. Normally I use for loop or anonymous delegate to do it like this:
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