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Why is super.super.method(); not allowed in Java?
...- RedItems can always be confident that the items it contains are all red. Now suppose we were able to call super.super.add():
public class NaughtyItems extends RedItems
{
@Override
public void add(Item item)
{
// I don't care if it's red or not. Take that, RedItems!
sup...
What is polymorphism, what is it for, and how is it used?
...ism and inheritance are all closely-related concepts and they're vital to know. There have been many "silver bullets" during my long career which basically just fizzled out but the OO paradigm has turned out to be a good one. Learn it, understand it, love it - you'll be glad you did :-)
(a) I ori...
What's the $unwind operator in MongoDB?
...s.funded_year"
} }
])
If we look at the funding_rounds array, we know that for each funding_rounds, there is a raised_amount and a funded_year field. So, unwind will for each one of the documents that are elements of the funding_rounds array produce an output document. Now, in this example,...
How to re-create database for Entity Framework?
...to say that it ran this script correctly. Go and check it out if you like.
Now, uncomment that code and save.
You can run Update-Database again if you want to check that EF thinks its up to date. It won't run the Up step with all of the CreateTable commands because it thinks it's already done this.
...
Why doesn't Internet Explorer 11 honour conditional comments even when emulating Internet Explorer 8
...
@ Andrew Thank you. Now I found the setting. The problem was the german translation. They translated "user agent" with "Zeichenfolge des Benutzer-Agents" and I thought this meant the charset. Some things should not be translated ;)
...
How to implement the Android ActionBar back button?
...ress the back button. This should be done in the AndroidManifest.xml too.
Now you can enable the back button in the onCreate method of your "child" activity.
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getActionBar().setDisplayHomeAsUp...
How to fast-forward a branch to head?
...
I don't know if the origin/master portion is required or if it sensibly defaults, but I found it useful to make an alias for fast forward so I wanted to make sure the upstream branch is used instead of hard coding it to origin/master:...
Illegal string offset Warning PHP
...ort"]=> string(5) "11211" } string(5) "m_prefix" PHP 5.4 now $xx['host'] threw the warning correctly.
– thesonix
Mar 26 '12 at 9:17
...
Best practices to handle routes for STI subclasses in rails
...rson < Contact
def self.model_name
Contact.model_name
end
end
Now url_for @person will map to contact_path as expected.
How it works: URL helpers rely on YourModel.model_name to reflect upon the model and generate (amongst many things) singular/plural route keys. Here Person is basical...
Differences between fork and exec
...d process (parent) as its parent PID (PPID). Because the two processes are now running exactly the same code, they can tell which is which by the return code of fork - the child gets 0, the parent gets the PID of the child. This is all, of course, assuming the fork call works - if not, no child is c...