How can you handle sorting for complex objects with multiple criteria using the Comparable interface? Provide an example.

The Comparable interface in Java is a mechanism that allows you to define a custom order or sorting logic for objects of a class. When a class implements the Comparable interface, it must provide an implementation for the compareTo method. This method defines how objects of that class should be compared to each other for the purpose of sorting.

By implementing the Comparable interface, you enable objects of your class to be sorted based on your specified criteria. This is particularly useful when dealing with complex objects that need to be sorted in a specific order, such as sorting employees by name, age, and salary as demonstrated in the code example. The compareTo method returns a negative integer if the current object is less than the object being compared, zero if they are equal, and a positive integer if the current object is greater, allowing for flexible and customized sorting of objects.