public int indexOf(String str,
int fromIndex)
Returns the index within this string of the first occurrence of the specified substring, starting at the specified index.
The returned index is the smallest value k for which:
k >= fromIndex && this.startsWith(str, k)
If no such value of k exists, then -1 is returned.
Parameters:
str - the substring to search for.
fromIndex - the index from which to start the search.
Returns:
the index of the first occurrence of the specified substring, starting at the specified index, or -1 if there is no such occurrence.