How do I use wildcards in Java?

How do I use wildcards in Java?

Wildcards in Java are represented by the question mark (?) and are used in generics to denote an unknown type. They help in making your code more flexible.

Can you give me an example of using wildcards?

Sure! For instance, if you have a method that accepts a list of any type, you can use List<?> to indicate that it can accept a list of any object type.

What are the different types of wildcards?

There are three types of wildcards: unbounded wildcards (?), upper bounded wildcards (extends), and lower bounded wildcards (super). Each serves a different purpose in generics.

When should I use upper bounded wildcards?

Use upper bounded wildcards when you want to restrict the unknown type to a specific type or its subtypes, allowing for more flexibility in method parameters.