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What is the difference between public, protected, package-private and private in Java?
...ess modifiers, namely the default (package private), public , protected and private , while making class and interface and dealing with inheritance?
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Android emulator shows nothing except black screen and adb devices shows “device offline”
I am just trying to start development in Android.
So, the problem is that when I try to launch an emulator by issuing the command emulator @A2 , an emulator comes up on the screen. But even after waiting for as long as 2-3 hrs, all it shows is a black screen. Not even the android home screen or t...
Can (domain name) subdomains have an underscore “_” in it?
...perfectly legal to have
an underscore in a domain name. Let me quote the standard, RFC
2181, section 11, "Name syntax":
The DNS itself places only one restriction on the particular labels
that can be used to identify resource records. That one
restriction relates to the length of the label ...
How does Apple find dates, times and addresses in emails?
...n an email contains a date, time or location, the text becomes a hyperlink and it is possible to create an appointment or look at a map simply by tapping the link. It not only works for emails in English, but in other languages also. I love this feature and would like to understand how they do it.
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How do multiple clients connect simultaneously to one port, say 80, on a server? [duplicate]
I understand the basics of how ports work. However, what I don't get is how multiple clients can simultaneously connect to say port 80. I know each client has a unique (for their machine) port. Does the server reply back from an available port to the client, and simply state the reply came from 80? ...
What's the difference between @Component, @Repository & @Service annotations in Spring?
Can @Component , @Repository and @Service annotations be used interchangeably in Spring or do they provide any particular functionality besides acting as a notation device?
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This app won't run unless you update Google Play Services (via Bazaar)
I'm testing out the new Google Maps API V2 for Android, and I'm getting this message when the app launches:
12 Answers
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What is the difference between “instantiated” and “initialized”?
...in C# are in 1 of 2 groups. Value types or Reference types. Types like int and DateTime are value types. In contrast, any class you create is a reference type. C# strings are also a reference type. Most things in the .NET framework are reference types.
Parts of a Variable
There is the variable nam...
Should we pass a shared_ptr by reference or by value?
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This question has been discussed and answered by Scott, Andrei and Herb during Ask Us Anything session at C++ and Beyond 2011. Watch from 4:34 on shared_ptr performance and correctness.
Shortly, there is no reason to pass by value, unless the goal is to sha...
How to implement classic sorting algorithms in modern C++?
The std::sort algorithm (and its cousins std::partial_sort and std::nth_element ) from the C++ Standard Library is in most implementations a complicated and hybrid amalgamation of more elementary sorting algorithms , such as selection sort, insertion sort, quick sort, merge sort, or heap sort....