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Implementation difference between Aggregation and Composition in Java
I'm aware of the conceptual differences between Aggregation and Composition. Can someone tell me the implementation difference in Java between them with examples?
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iPhone Data Usage Tracking/Monitoring
...istics for each network interface.
In general en0 is your Wi-Fi interface and pdp_ip0 is your WWAN interface.
There is no good way to get information wifi/cellular network data since, particular date-time!
Data statistic (ifa_data->ifi_obytes and ifa_data->ifi_ibytes) are stored from prev...
App Inventor 2开发简单计算器 - App Inventor 2 中文网 - 清泛IT论坛，有思想、有深度
计算器这个看似简单的应用，当你一旦着手去制作时，就会发现写出来的程序漏洞百出，那些在人类看来理所当然的逻辑，对于计算机来说，却是浑然不知，一定要将每个细节都照顾到，程序才能如你所愿地运行，否则就会出现...
Please explain the exec() function and its family
What is the exec() function and its family? Why is this function used and how does its work?
7 Answers
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Appending a vector to a vector [duplicate]
Assuming I have 2 standard vectors:
4 Answers
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Cannot refer to a non-final variable inside an inner class defined in a different method
...TheSoul points out.
This is why it doesn't work:
The variables lastPrice and price are local variables in the main() method. The object that you create with the anonymous class might last until after the main() method returns.
When the main() method returns, local variables (such as lastPrice and...
Is Using .NET 4.0 Tuples in my C# Code a Poor Design Decision?
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Tuples are great if you control both creating and using them - you can maintain context, which is essential to understanding them.
On a public API, however, they are less effective. The consumer (not you) has to either guess or look up documentation, especially for thin...
How to check if Location Services are enabled?
I'm developing an app on Android OS. I don't know how to check if Location Services are enabled or not.
22 Answers
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ViewPager PagerAdapter not updating the View
...when you call notifyDataSetChanged(), the view pager will remove all views and reload them all. As so the reload effect is obtained.
The second option, suggested by Alvaro Luis Bustamante (previously alvarolb), is to setTag() method in instantiateItem() when instantiating a new view. Then instead o...
Why aren't pointers initialized with NULL by default?
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We all realize that pointer (and other POD types) should be initialized.
The question then becomes 'who should initialize them'.
Well there are basically two methods:
The compiler initializes them.
The developer initializes them.
Let us assume tha...