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Storing a Map using JPA
...
JPA 2.0 supports collections of primitives through the @ElementCollection annotation that you can use in conjunction with the support of java.util.Map collections.
Something like this should work:
@Entity
public class Example {...
What is a Portable Class Library?
... This is the best interview/video I've seen to date covering .NET Standard 2.0
UPDATE Sep 27 2016: .NET Standard 2.0 announcement post has more good info
UPDATE Jun 6 2016: This article explains well how the .NETStandard library mechanism supersedes much of PCL
UPDATE Jul 10 2013: Excellent state...
How do you trigger a block after a delay, like -performSelector:withObject:afterDelay:?
... 3.42
// Delay 2 seconds
DispatchQueue.main.asyncAfter(deadline: .now() + 2.0) {
print("Sum of times: \(time1 + time2)")
}
Swift 2
let time1 = 8.23
let time2 = 3.42
// Delay 2 seconds
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, Int64(2.0 * Double(NSEC_PER_SEC))), dispatch_get_main_queue...
How do I go straight to template, in Django's urls.py?
...
Django 2.0+
Use the class based generic views but register with the django 2.0+ pattern.
from django.urls import path
from django.views.generic import TemplateView
urlpatterns = [
path('foo/', TemplateView.as_view(template_na...
Positioning MKMapView to show multiple annotations at once
... region.center.latitude = (southWest.latitude + northEast.latitude) / 2.0;
region.center.longitude = (southWest.longitude + northEast.longitude) / 2.0;
region.span.latitudeDelta = meters / 111319.5;
region.span.longitudeDelta = 0.0;
_savedRegion = [_mapView regi...
How to migrate/convert from SVN to Mercurial (hg) on windows
...any thanks to bgever for pointing out in the comments that with TortoiseHg 2.0, enabling the convert extension is easier than ever. As he says
With TortoiseHG 2.0 this has been made
much simpler: Start the TortoiseHG
Workbench from the Start menu. Select
File --> Settings. Select Exten...
Create array of symbols
...original answer was written back in September '11, but, starting from Ruby 2.0, there is a shorter way to create an array of symbols! This literal:
%i[address city state postal country]
will do exactly what you want.
shar...
Django, creating a custom 500/404 error page
...ews.handler404'
handler500 = 'my_app.views.handler500'
Update for Django 2.0
Signatures for handler views were changed in Django 2.0:
https://docs.djangoproject.com/en/2.0/ref/views/#error-views
If you use views as above, handler404 will fail with message:
"handler404() got an unexpected ke...
C# Lambda expressions: Why should I use them?
...
Lambda's cleaned up C# 2.0's anonymous delegate syntax...for example
Strings.Find(s => s == "hello");
Was done in C# 2.0 like this:
Strings.Find(delegate(String s) { return s == "hello"; });
Functionally, they do the exact same thing, its ...
Default behavior of “git push” without a branch specified
...considered to be matching.
This used to be the default, but not since Git 2.0 (simple is the new default).
upstream: push the current branch to its upstream branch (tracking is a deprecated synonym for upstream)
current: push the current branch to a branch of the same name
simple: (new in Git 1.7.1...