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Why does Eclipse complain about @Override on interface methods?
...n Java 5.
Make sure that your IDE projects are setup to use a Java 6 JRE, and that the "source compatibility" is set to 1.6 or greater:
Open the Window > Preferences dialog
Browse to Java > Compiler.
There, set the "Compiler compliance level" to 1.6.
Remember that Eclipse can override th...
Should I use the datetime or timestamp data type in MySQL?
Would you recommend using a datetime or a timestamp field, and why (using MySQL)?
39 Answers
...
What is the rationale behind having companion objects in Scala?
...eton) for a class is needed? Why would I want to create a class, say Foo and also create a companion object for it?
7 Ans...
Override valueof() and toString() in Java enum
...d (getEnum in the sample code below) which returns the value that you need and change your client to use this method instead.
public enum RandomEnum {
StartHere("Start Here"),
StopHere("Stop Here");
private String value;
RandomEnum(String value) {
this.value = value;
...
Permission denied on accessing host directory in Docker
...
See this Project Atomic blog post about Volumes and SELinux for the full story.
Specifically:
This got easier recently since Docker finally merged a patch which
will be showing up in docker-1.7 (We have been carrying the patch in
docker-1.6 on RHEL, CentOS, and Fe...
Iterate a list as pair (current, next) in Python
...ometimes need to iterate a list in Python looking at the "current" element and the "next" element. I have, till now, done so with code like:
...
MongoDB: Combine data from multiple collections into one..how?
...you can use as an _id.
For example, let's say you have a users collection and a comments collection and you want to have a new collection that has some user demographic info for each comment.
Let's say the users collection has the following fields:
_id
firstName
lastName
country
gender
age
And...
How does Python 2 compare string and int? Why do lists compare as greater than numbers, and tuples g
...ring for string, numeric ordering for integers).
When you order a numeric and a non-numeric type, the numeric type comes first.
>>> 5 < 'foo'
True
>>> 5 < (1, 2)
True
>>> 5 < {}
True
>>> 5 < [1, 2]
True
When you order two incompatible types where n...
How to redirect to a 404 in Rails?
...
raise ActionController::RoutingError.new('Not Found')
end
Rails also handles AbstractController::ActionNotFound, and ActiveRecord::RecordNotFound the same way.
This does two things better:
1) It uses Rails' built in rescue_from handler to render the 404 page, and
2) it interrupts the executi...
How to extract the first two characters of a string in shell scripting?
...
Probably the most efficient method, if you're using the bash shell (and you appear to be, based on your comments), is to use the sub-string variant of parameter expansion:
pax> long="USCAGol.blah.blah.blah"
pax> short="${long:0:2}" ; echo "${short}"
US
This will set short to be the f...