Can Generic Methods in Java Return Multiple Types?

Generic Methods in Java: Understanding Multiple Return Types

In Java, generic methods provide the ability to operate on a wide range of types using a single method definition. This can be useful in situations where the exact type of data being handled is not known in advance.

Consider the following method declaration:

public <E extends Foo> List<E> getResult(String s);

where Foo is a class defined elsewhere. At first glance, it may appear that this method has two return types: a list and an unknown type E. However, this is not the case.

Breaking Down the Method Declaration

• : This is a generic type declaration. It introduces a new generic type parameter E, which can be any subclass of Foo. This allows the method to work with any type that extends Foo.
• List: This is the actual return type of the method. It is a list containing elements of type E. Since E can be any subclass of Foo, the method can return a list of any type that extends Foo.

In Summary

The method getResult is a generic method that can operate on different types of data by specifying a generic type parameter. It returns a list containing elements of that type, allowing for flexibility in handling data of different types.

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