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Why should a Java class implement comparable?
Why is Java Comparable used? Why would someone implement Comparable in a class? What is a real life example where you need to implement comparable?
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How to convert a currency string to a double with jQuery or Javascript?
I have a text box that will have a currency string in it that I then need to convert that string to a double to perform some operations on it.
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What is the difference between 'E', 'T', and '?' for Java generics?
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Well there's no difference between the first two - they're just using different names for the type parameter (E or T).
The third isn't a valid declaration - ? is used as a wildcard which is used when providing a type argument, e.g. List<?> foo = ... means that foo refers to a list of s...
What is a semaphore?
... a programming concept that is frequently used to solve multi-threading problems. My question to the community:
14 Answer...
ANTLR: Is there a simple example?
I'd like to get started with ANTLR, but after spending a few hours reviewing the examples at the antlr.org site, I still can't get a clear understanding of the grammar to Java process.
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How to thoroughly purge and reinstall postgresql on ubuntu? [closed]
Somehow I've managed to completely bugger the install of postgresql on Ubuntu karmic. I want to start over from scratch, but when I "purge" the package with apt-get it still leaves traces behind such that the reinstall configuration doesn't run properly.
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PostgreSQL “DESCRIBE TABLE”
How do you perform the equivalent of Oracle's DESCRIBE TABLE in PostgreSQL (using the psql command)?
22 Answers
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How can I parse a CSV string with JavaScript, which contains comma in data?
I have the following type of string
17 Answers
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dplyr: “Error in n(): function should not be called directly”
I am attempting to reproduce one of the examples in the dplyr package but am getting this error message. I am expecting to see a new column n produced with the frequency of each combination. What am I missing? I triple checked that the package is loaded.
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Bash script absolute path with OS X
I am trying to obtain the absolute path to the currently running script on OS X.
15 Answers
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