Thread: Have I done this efficiently ?

Can you define "efficient"? Then maybe we could answer your question.

Originally Posted by Cornix

Can you define "efficient"? Then maybe we could answer your question.

Is there a better way to doing, or is this a fast and neat way of doing this? If you know what I mean

Originally Posted by Norm

What is the purpose of this statement:

  code += "";

Oh haha, yea just deleted that right there thanks man

I have some general tips for you:
1) If you want to define constant values (like in C or C++) you dont use "static" but instead "static final" for variables.
A static variable is not constant, its value can still be changed by the program at any point in time. Judging from your code I would assume that you want to make "repeat", "characters" and "dash" to static final variables. In this case it is also convention to write the variable names in all uppercase.

2) This method:

	private static int randomize(int range) {
		return (int) (java.lang.Math.random() * (range + 1));
	}

is pointless because the Random class already gives you access to a method which does practically the same.
Just create an object of the Random class instead of using the static Math methods, those are not recommended anyways.

3) Why does your class have a static variable called "code"? This variable is not used at all.

4) When modifying Strings you should use StringBuilder instead of concatenating using the "+"-operator. Read up on the StringBuilder documentation for more information on its uses and purpose.

Originally Posted by Cornix

I have some general tips for you:
1) If you want to define constant values (like in C or C++) you dont use "static" but instead "static final" for variables.
A static variable is not constant, its value can still be changed by the program at any point in time. Judging from your code I would assume that you want to make "repeat", "characters" and "dash" to static final variables. In this case it is also convention to write the variable names in all uppercase.

2) This method:

	private static int randomize(int range) {
		return (int) (java.lang.Math.random() * (range + 1));
	}

is pointless because the Random class already gives you access to a method which does practically the same.
Just create an object of the Random class instead of using the static Math methods, those are not recommended anyways.

3) Why does your class have a static variable called "code"? This variable is not used at all.

4) When modifying Strings you should use StringBuilder instead of concatenating using the "+"-operator. Read up on the StringBuilder documentation for more information on its uses and purpose.

Thanks a lot for all the tips, I'll change up the variable names, and also code is being used isn't it? By main and by random

			"1", "2", "3", "4", "5", "5", "6", "7", "8", "9",
			"A", "B", "C", "D", "E", "F", "G", "H", "I", "J",
			"K", "L", "M", "N", "O", "P", "Q", "R", "S", "T",
			"U", "V", "W", "X", "Y", "Z"

Efficient or not, I would probably try to find some way to generate a couple tuples of character types; The first one would include the numerical characters and the second one would include the (upper case) letters. Then I would merge (copy) the content of these arrays into the final keys array (probably also containing character types and not strings).

It wouldn't be easier to do, and it might not even take less code to achieve. But just as an exercise in elegance. :-) Imagine you were using a hundred or so characters in your codes - this is where the efficiency would code in. At least as far as coding is concerned.

To take this even further - perhaps it would be possible to generate these codes without using an array of characters? Probably by using the same method theorized above for creating the numerical and alphabetical arrays respectively.

I'm currently not sure how to do what I suggest myself, but I'm guessing that all characters are indexed somewhere and can be readily accessed by some method in the Java API. I'm sure someone else could point us in the right direction, but the fun is in figuring these things out for yourself, not? ;-)

Originally Posted by Zack Davidson

Thanks a lot for all the tips, I'll change up the variable names, and also code is being used isn't it? By main and by random

Nope.
You have a method called "generateCode", this method is returning a String. The returned String is being used by your main method.
Now, this String just happened to be the same String that is referenced by the variable code, but that does not mean that the variable is useful.
If you remove the static variable code your program would still do the same.

Originally Posted by Cornix

I have some general tips for you:
1) If you want to define constant values (like in C or C++) you dont use "static" but instead "static final" for variables.
A static variable is not constant, its value can still be changed by the program at any point in time. Judging from your code I would assume that you want to make "repeat", "characters" and "dash" to static final variables. In this case it is also convention to write the variable names in all uppercase.

2) This method:

	private static int randomize(int range) {
		return (int) (java.lang.Math.random() * (range + 1));
	}

is pointless because the Random class already gives you access to a method which does practically the same.
Just create an object of the Random class instead of using the static Math methods, those are not recommended anyways.

3) Why does your class have a static variable called "code"? This variable is not used at all.

4) When modifying Strings you should use StringBuilder instead of concatenating using the "+"-operator. Read up on the StringBuilder documentation for more information on its uses and purpose.

how does it look now

--- Update ---

Originally Posted by Cornix

Nope.
You have a method called "generateCode", this method is returning a String. The returned String is being used by your main method.
Now, this String just happened to be the same String that is referenced by the variable code, but that does not mean that the variable is useful.
If you remove the static variable code your program would still do the same.

yea ive changed this up a bit

Still the same, but now with a StringBuilder instead of the code variable.
That StringBuilder does not need to be a static variable, just make it local within the generateCode method.

Originally Posted by Cornix

Still the same, but now with a StringBuilder instead of the code variable.
That StringBuilder does not need to be a static variable, just make it local within the generateCode method.

Ok done

--- Update ---

Edit: i need it because of the main method