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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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Rails 3: Get Random Record
...irst
Actually, in Rails 3 all examples will work. But using order RANDOM is quite slow for big tables but more sql-style
UPD. You can use the following trick on an indexed column (PostgreSQL syntax):
select *
from my_table
where id >= trunc(
random() * (select max(id) from my_table) + 1
)...
Getting a list of all subdirectories in the current directory
Is there a way to return a list of all the subdirectories in the current directory in Python?
27 Answers
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Using str_replace so that it only acts on the first match?
...) that only replaces the first occurrence of $search in the $subject . Is there an easy solution to this, or do I need a hacky solution?
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How can I distribute python programs?
My application looks like this:
7 Answers
7
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What is q=0.5 in Accept* HTTP headers?
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This is called a relative quality factor. It specifies what language the user would prefer, on a scale of 0 to 1, as can be seen from the HTTP/1.1 Specification, §14.4:
Each language-range MAY be given an associated quality ...
How should I escape strings in JSON?
... library in your language, you don't want to use one (I wouldn't suggest this¹), or you're writing a JSON library, read on.
Escape it according to the RFC. JSON is pretty liberal: The only characters you must escape are \, ", and control codes (anything less than U+0020).
This structure of escapi...
How to cast an Object to an int
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If you're sure that this object is an Integer :
int i = (Integer) object;
Or, starting from Java 7, you can equivalently write:
int i = (int) object;
Beware, it can throw a ClassCastException if your object isn't an Integer and a NullPointer...
What does `:_*` (colon underscore star) do in Scala?
I have the following piece of code from this question :
4 Answers
4
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Proper way to implement IXmlSerializable?
...urn null and ReadXml should move to the next element before returning. Is this true? And what about WriteXml - should it write a root element for the object or is it assumed that the root is already written? How should child objects be treated and written?
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