Interface instancing (3 ways)

import java.util.function.BinaryOperator;
// A BinaryOperator Represents an operation upon two operands of the same type, producing a result of the same type
// as the operands. This interface contains one method "apply".

/**
 * Class that implements BinaryOperator<Boolean> to perform the "or" operation on two booleans.
 */
class Or implements BinaryOperator<Boolean>{
    @Override
    public Boolean apply(Boolean b1, Boolean b2) {
        return b1 || b2;
    }
}

public class Main {
    // 1 -------------------
    // Using a fully defined class "Or" (see above)
    BinaryOperator<Boolean> or = new Or();

    // 2 -------------------
    // Using an anonymous class (No class name; looks like you're making an instance of this interface. In this case you
    // must implement all methods of the interface in the body:
    BinaryOperator<Boolean> implies = new BinaryOperator<Boolean>() {
        @Override
        public Boolean apply(Boolean b1, Boolean b2) {
            return !b1 || b2;
        }
    };

    // 3 -------------------
    // Using a lambda expression to implement an instance of this interface is possible for any Functional Interface.
    // A functional interface is an interface with just one abstract method. See the @FunctionalInterface annotation
    // in the definition of BinaryOperator; this prevents the interface from defining more than one method.
    BinaryOperator<Boolean> and = (b1, b2) -> b1 && b2;
}