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Why are #ifndef and #define used in C++ header files?
...his case HEADERFILE_H) is defined. Then if it's not defined, it defines it and continues to the rest of the page.
When the code is included again, the first ifndef fails, resulting in a blank file.
That prevents double declaration of any identifiers such as types, enums and static variables.
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Good reasons to prohibit inheritance in Java?
... Item 19 of Joshua Bloch's excellent book "Effective Java", called "Design and document for inheritance or else prohibit it". (It's item 17 in the second edition and item 15 in the first edition.) You should really read it, but I'll summarize.
The interaction of inherited classes with their parent...
When and why JPA entities should implement Serializable interface?
The question is in the title. Below I just described some of my thoughts and findings.
14 Answers
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What are database normal forms and can you give examples? [closed]
...imply normalization, which is a process of organizing columns (attributes) and tables (relations) to reduce data redundancy and improve data integrity. (as written on Wikipedia ).
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Algorithm for Determining Tic Tac Toe Game Over
I've written a game of tic-tac-toe in Java, and my current method of determining the end of the game accounts for the following possible scenarios for the game being over:
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How do I add an existing directory tree to a project in Visual Studio?
...ucture for my project on the file system. How do I include all the folders and files in a project, keeping the structure?
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Better way of incrementing build number?
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If I understand your question correctly, you want to modify the Project-Info.plist file, which is a part of the standard project template of Xcode?
The reason I ask this is that Project-Info.plist normally is under version control, and...
What is Java String interning?
What is String Interning in Java, when I should use it, and why ?
7 Answers
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What is the difference between a weak reference and an unowned reference?
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Both weak and unowned references do not create a strong hold on the referred object (a.k.a. they don't increase the retain count in order to prevent ARC from deallocating the referred object).
But why two keywords? This distinction has...
How do I update a GitHub forked repository?
I recently forked a project and applied several fixes. I then created a pull request which was then accepted.
21 Answers
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