Question

I have the following abstract class:

public abstract class AbstractGroup {

private String name;
.
.
.
}

I have two empty classes that extend this abstract class:

public class GroupA extends AbstractGroup {
}

public class GroupB extends AbstractGroup {
}

Is there a way to cast the following without getting a ClassCastException:
(group is of type GroupA)

group = (GroupB)group;

I need this object instance to become GroupB.

Answer 1

It’s not possible. You cannot cast classes horizontally but only vertically. GroupA is not the subtype of GroupB so the exception always will be raised.