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How to change Vagrant 'default' machine name?
...reated a directory called nametest and ran
vagrant init precise64 http://files.vagrantup.com/precise64.box
to generate a default Vagrantfile. Then I opened the VirtualBox GUI so I could see what names the boxes I create would show up as.
Default Vagrantfile
Vagrant.configure('2') do |config|...
Save image from URL by paperclip
...ay:
require "open-uri"
class User < ActiveRecord::Base
has_attached_file :picture
def picture_from_url(url)
self.picture = open(url)
end
end
Then simply :
user.picture_from_url "http://www.google.com/images/logos/ps_logo2.png"
...
Disable ActiveRecord for Rails 4
...
For existing applications:
1. Remove database adapter gems from your Gemfile (mysql2, sqlite3, etc.)
2. Change your config/application.rb
Remove require 'rails/all line and require frameworks (among those available in your rails version, the list varies, do not just copy) you want to use, for e...
At runtime, find all classes in a Java application that extend a base class
...the ServiceLoader mechanism.
Also many people roll their own by having a file in a well known classpath location (i.e. /META-INF/services/myplugin.properties) and then using ClassLoader.getResources() to enumerate all files with this name from all jars. This allows each jar to export its own provi...
Resetting remote to a certain commit
...
If you want a previous version of file, I would recommend using git checkout.
git checkout <commit-hash>
Doing this will send you back in time, it does not affect the current state of your project, you can come to mainline
git checkout mainline
...
Batch files - number of command line arguments
Just converting some shell scripts into batch files and there is one thing I can't seem to find...and that is a simple count of the number of command line arguments.
...
Fatal error: Maximum execution time of 300 seconds exceeded
...
add it at the very top of your php file
– Tules
Oct 6 '11 at 21:24
2
...
Create Directory if it doesn't exist with Ruby
... nested directories. Assuming foo does not exist, you will receive no such file or directory error for:
Dir.mkdir 'foo/bar'
# => Errno::ENOENT: No such file or directory - 'foo/bar'
To create nested directories at once, FileUtils is needed:
require 'fileutils'
FileUtils.mkdir_p 'foo/bar'
# =&...
Is there a way to 'uniq' by column?
I have a .csv file like this:
8 Answers
8
...
Can we instantiate an abstract class?
... compile both your classes. Suppose you put those classes in two different files:
My.java:
abstract class My {
public void myMethod() {
System.out.print("Abstract");
}
}
Poly.java:
class Poly extends My {
public static void main(String a[]) {
My m = new My() {};
...