Question

I’m not really sure how to word this, but basically I want to read in an rgb color in xxx, xxx, xxx format and store each xxx in an array. I am making a program to convert rgb into hexadecimal. Until I get my gui created (which may take me some time) I am executing and inputting in the terminal.

Currently this is what I am doing:

System.out.println("Enter the first set:");
rgb[0] = new Scanner(System.in).nextInt();`
System.out.println("Enter the second set:");
rgb[1] = new Scanner(System.in).nextInt();
System.out.println("Enter the third set:");
rgb[2] = new Scanner(System.in).nextInt(); 

• I have seen people use .split(","), is this the best way to do what I want?
• Would a regular expression work better?
• Anyone know any tutorials that I could use? Most of the ones I have found have just left me more confused than I already was.

Just so you know I am not doing this for a project (before anyone accuses me). I already have the algorithm and everything else works except for this.

Answer 1

Here are my suggestions:

• Don’t create a new Scanner instance each time you want to read input. Just create one at the beginning of the program and reuse it throughout.

• The split method takes a regular expression as its argument, and returns a String[] (splitting the string on each match of its argument). So if you’re planning on parsing a string of the form "xxx, xxx, xxx" then .split(",\\s*") is probably your best bet. \s matches any whitespace character and \s* matches \s zero or more times.

• I’m assuming rgb is an int[], so you could loop through your String[] that was obtained from split (as described above), call Integer.parseInt on each element, and add the parsed int to rgb.

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Relevant documentation

• String#split
• Integer#parseInt