I apologize, but there is no class called "OptBoolean" in the Apache Commons IO library. This library provides utility classes for working with IO operations such as file manipulation, input/output streams, and file filters. It doesn't include any functionality for handling boolean values with optionality.

However, you can use the org.apache.commons.lang3.BooleanUtils class from the Apache Commons Lang library to handle boolean values with optionality.

Here's an example of how you can use the BooleanUtils.toBooleanObject(String str) method to convert a string to an OptBoolean:

import org.apache.commons.lang3.BooleanUtils;

public class OptBooleanExample {
    public static void main(String[] args) {
        String str = "true";
        Boolean optBoolean = BooleanUtils.toBooleanObject(str);
        if (optBoolean == null) {
            System.out.println("The string is not a valid boolean");
        } else {
            System.out.println(optBoolean);
        }
    }
}

This will output the following:

true

You can use similar approach to convert other boolean representations like int, char etc.

The toBooleanObject() method returns the Boolean object that corresponds to the input string. If the input string is not a valid boolean representation, then it returns null.

Also, it's worth noting that Java 8 has introduced a new class java.util.Optional which can be used to represent a value that may or may not be present. You can use it to wrap a boolean value and check if the value is present or not.