public boolean hasNextInt()

Returns true if the next token in this scanner's input can be interpreted as an int value in the default radix using the nextInt() method. The scanner does not advance past any input.

Returns:

true if and only if this scanner's next token is a valid int value

Throws:

IllegalStateException - if this scanner is closed

https://docs.oracle.com/javase/7/docs/api/java/util/Scanner.html#hasNextInt()