What is a bounded type parameter in Java Generics?

Java MCQ: What is a bounded type parameter in Java Generics?

Answer:

Explanation:

A bounded type parameter in Java Generics is a type parameter that is restricted to a specific set of types. This allows you to define constraints on the types that can be used with a generic class, interface, or method, ensuring that the type meets certain requirements.

Bouned type parameters are specified using the extends keyword, which can be used with both classes and interfaces. For example, consider the following generic class with a bounded type parameter:

public class Box<T extends Number> {
    private T value;

    public Box(T value) {
        this.value = value;
    }

    public T getValue() {
        return value;
    }
}

In this example, the type parameter T is bounded by the Number class. This means that the Box class can only be used with types that are subclasses of Number, such as Integer, Double, and Float. This constraint ensures that the methods and fields within the Box class can safely perform operations specific to numbers, such as arithmetic operations.

Bounded type parameters are useful when you want to create generic code that is flexible but still enforces certain type constraints. For instance, if you are writing a method that performs calculations on numeric data, you can use a bounded type parameter to ensure that the method can only be called with numeric types.

In summary, bounded type parameters in Java Generics provide a way to create more robust and type-safe code by restricting the types that can be used with a generic class, interface, or method to a specific set of types.

Reference links:

https://www.rameshfadatare.com/learn-java-programming/
https://www.javaguides.net/p/java-tutorial-learn-java-programming.html