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How to check if a String is numeric in Java
How would you check if a String was a number before parsing it?
39 Answers
39
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Check if element exists in jQuery [duplicate]
How do I check if an element exists if the element is created by .append() method?
$('elemId').length doesn't work for me.
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What does SQL clause “GROUP BY 1” mean?
...answered Sep 12 '11 at 19:12
YuckYuck
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Add a dependency in Maven
How do I take a jar file that I have and add it to the dependency system in maven 2? I will be the maintainer of this dependency and my code needs this jar in the class path so that it will compile.
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How do I convert an array object to a string in PowerShell?
...# This Is a cat
"$a"
# This-Is-a-cat
$ofs = '-' # after this all casts work this way until $ofs changes!
"$a"
Using operator join
# This-Is-a-cat
$a -join '-'
# ThisIsacat
-join $a
Using conversion to [string]
# This Is a cat
[string]$a
# This-Is-a-cat
$ofs = '-'
[string]$a
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Check existence of input argument in a Bash shell script
I need to check the existence of an input argument. I have the following script
11 Answers
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Center a 'div' in the middle of the screen, even when the page is scrolled up or down?
I have in my page a button which when clicked displays a div (popup style) in the middle of my screen.
5 Answers
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Why doesn't String switch statement support a null case?
...ead throws NullPointerException ? See the commented line below (example taken from the Java Tutorials article on switch ):
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nginx: send all requests to a single html page
...istory.getState() to route the requests in my javascript app. It seems like it should be a simple thing to do?
6 Answers
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Right query to get the current number of connections in a PostgreSQL DB
...alent. The equivalent version of the first one would be:
SELECT sum(numbackends) FROM pg_stat_database;
In that case, I would expect that version to be slightly faster than the second one, simply because it has fewer rows to count. But you are not likely going to be able to measure a difference.
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