I apologize, but there is no such class as "NumberInput" in the Apache Commons IO library. It seems that you might be confusing it with other class or package. Apache Commons IO focuses on providing utility classes for file and I/O operations, and it doesn't have a class specifically for parsing numbers from an input source.

Java provides several classes for parsing numbers from a string such as Integer.parseInt(), Long.parseLong(), Double.parseDouble(), etc. You can use these methods to parse numbers from a string.

Here is an example of using the Integer.parseInt() method to parse an integer from a string:

public class NumberInputExample {
    public static void main(String[] args) {
        String input = "123";
        int number = Integer.parseInt(input);
        System.out.println(number);
    }
}

This will output:

123

You can also use the Long.parseLong(), Double.parseDouble(), Float.parseFloat() and other parse methods to parse long, double and float values respectively.

You can also use the NumberFormat class to parse numbers in a locale-specific format.