Question

I have a two dimensional array that contains pairs of strings. If one string is found it should replace it with its pair.

The code:

 for (int i = 0; i < pairs.length; i++) {
        if (name.contains(pairs[i][0])) {
            name.replaceAll(pairs[i][0], abbr[i][1]);
        }
    }

It is not replacing the strings. What is the error?

Answer 1

You are neglecting to assign the result of replaceAll, and so the modification is lost.

Perhaps you want to keep the modified string as name:

for (int i = 0; i < pairs.length; i++) {
    if (name.contains(pairs[i][0])) {
        name = name.replaceAll(pairs[i][0], abbr[i][1]);
    }
}

Note that java String objects are immutable, so calling name.replaceAll doesn’t modify name, it returns a new String with the modifications.