is there a way to integrate a switch with String.contains("")?

Question

I need to check if a String object contains() various substrings and based on the results have different pieces of code execute. Currently I have a series of else if. I would like to convert it into a switch if possible. Is there a way to do this?

currently:

 if (SomeString.contains("someSubString")) {

    . . . do something

 } else if (SomeString.contains("anotherSubString")) {

    . . . do something else

 } else if (SomeString.contains("yetanotherSubString")) {

    . . . do something even more different

 }  
 .
 .
 .

Answer 1

When I have a situation like this, and really don't want to use else if, I do something like this:

String[] cases = {"someSubString", "anotherSubString", "yetanotherSubString"};

int i;
for(i = 0; i < cases.length; i++)
    if(SomeString.contains(cases[i])) break;

switch(i) {
    case 0: //someSubString
        System.out.println("do something");
    break;
    case 1: //anotherSubString
        System.out.println("do something else");
    break;
    case 2: //yetanotherSubString
        System.out.println("do something even more different");
    break;
    default:
        System.out.println("do nothing");
}

Of course, that has a couple of downsides. For starters, if you add another strings anywhere but the end, all the indices will shift, and you have to correct for that manually. Still, I think I have used something like that once or twice and thought it makes the code more readable. Presumably, the indices had some meaning in the program, thus coupling the 0...someSubString in a way meaningful to the problem.

Answer 2

You can't use a String variable in a switch, but you can use a char, maybe a specific char is diferent in all your strings?

For "someSubString", "anotherSubString" and "yetanotherSubString" you can use something like:

switch(SomeString.chatAt(0)) {
    case 's':
    case 'a':
    case 'y':
}

But this is only valid if you know all possible values of the string and a character of a specific position is diferent on all of them.