How to find nth occurance of a character in a String

Use the following code snippet to find the nth occurance of a character in a string.

/*
 * This method returns the position of nth occurance(starting from zero)
 *  of a character sequence in the given string.
 * It returns -1 if the character sequence is not found.
 */

public int nthOccurance(String str,int n,String srchStr)
{
    int pos = str.indexOf(srchStr, 0);
    while (n-- > 0 && pos != -1)
    {
        pos = str.indexOf(srchStr, pos+1);
        return pos;
    }
}

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