java - Using generics that extend a class -

i have class this:

public abstract class someclass<e extends anotherclass> {      private e somevariable;      public e formatvariable(){         e formatted = somevariable.format(); //format method in anotherclass, returns anotherclass         return formatted;     } } 

eclipse gives me error, "cannot convert anotherclass e"

i confused because in class decleration made e anotherclass or subclass of it, or @ least understanding of it.

what's going on here, , how can fix error?

format() returns anotherclass, don't want any anotherclass — want e specifically. if had this?

public class anotherclassred extends anotherclass {     @override     public anotherclass format() {         return new anotherclassblack();     } }  public class anotherclassblack extends anotherclass {     // note: *not* subclass of anotherclassred     ... 

with scenario, if things compiled formatvariable() return formatted instance anotherclassred, instance anotherclassblack; result classcastexception.

it sounds want format() return e, not anotherclass.