Tricky Rules

The method

public String substring(int beginIndex )

creates a new string. The original string is not changed. There are two tricky rules:

1. If beginIndex is exactly equal to the length of the original string, a substring is created, but it contains no characters (it is an empty string)
2. If beginIndex is greater than the length of the original string, or a negative value, an IndexOutOfBoundsException is thrown (and for now, your program crashes).