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Good or bad practice? Initializing objects in getter
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What you have here is a - naive - implementation of "lazy initialization".
Short answer:
Using lazy initialization unconditionally is not a good idea. It has its places but one has to take into consideration the impacts this solution has.
Background and explana...
How should I have explained the difference between an Interface and an Abstract class?
...Suppose you have 3 databases in your application. Then each and every implementation for that database needs to define the above 2 methods:
public class DBMySQL implements LoginAuth{
// Needs to implement both methods
}
public class DBOracle implements LoginAuth{
// Needs to im...
Differences between socket.io and websockets
...id using WebSockets directly unless you are very familiar with what environments they don't work and you are capable of working around those limitations.
This is a good read on both WebSockets and Socket.IO.
http://davidwalsh.name/websocket
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Are there other whitespace codes like   for half-spaces, em-spaces, en-spaces etc useful in HTML
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Firefox renders all of the above spaces as the same width, wider than one space in the font, except for nbsp, where it renders as one space and imposes the non-breaking character. A real shame. There are cases where only a character will do, for instance when padding is bei...
How to get different colored lines for different plots in a single figure?
...n different plots (consider using a few subplots on one figure), or
Use something other than color (i.e. marker styles or line thickness) to distinguish between them.
Otherwise, you're going to wind up with a very messy plot! Be nice to who ever is going to read whatever you're doing and don't...
Why are there two kinds of functions in Elixir?
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Just to clarify the naming, they are both functions. One is a named function and the other is an anonymous one. But you are right, they work somewhat differently and I am going to illustrate why they work like that.
Let's start with the second, fn. fn is a closure, similar to a lambda in...
Standard alternative to GCC's ##__VA_ARGS__ trick?
...d the use of GCC's ,##__VA_ARGS__ extension if you are willing to accept some hardcoded upper limit on the number of arguments you can pass to your variadic macro, as described in Richard Hansen's answer to this question. If you do not want to have any such limit, however, to the best of my knowledg...
What are MVP and MVC and what is the difference?
... of building user interfaces that many tools encourage you are likely to come across three design patterns called Model-View-Controller , Model-View-Presenter and Model-View-ViewModel . My question has three parts to it:
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MongoDB: Combine data from multiple collections into one..how?
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Although you can't do this real-time, you can run map-reduce multiple times to merge data together by using the "reduce" out option in MongoDB 1.8+ map/reduce (see http://www.mongodb.org/display/DOCS/MapReduce#MapReduce-Outputoptions). You need to have some ...
What does the brk() system call do?
According to Linux programmers manual:
8 Answers
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