The Function functional interface is a predefined interface introduced in Java 8 as part of the java.util.function package. It represents a function that accepts one input argument and produces one result. This interface is widely used in lambda expressions, Stream API operations, and functional programming. A key feature of the Function interface is that it enables developers to define reusable transformation logic, where an input object is converted into another form. For example, converting a String into its length, a Student object into a grade, or an entity into a DTO. Function is functional interface that takes one argument and produces a result , Syntax: Program1 : Write a program…