Question

Is there a simple way (instead of traversing manually all the string, or loop for indexOf) in order to find how many times, a character appears in a string?

Say we have “abdsd3$asda$asasdd$sadas” and we want that $ appears 3 times.

Answer 1

public int countChar(String str, char c)
{
    int count = 0;
    
    for(int i=0; i < str.length(); i++)
    {    if(str.charAt(i) == c)
            count++;
    }
    
    return count;
}

This is definitely the fastest way. Regexes are much much slower here, and possibly harder to understand.