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  1. Java Data Type Q&A
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1. java cast from List to List where B extends A    stackoverflow.com

is this possible? if not, why isn't this possible in Java? 

interface B extends A {}
public List<B> getList();
List<A> = getList(); // Type mismatch: cannot convert from List<B> to List<A>
I think the topic ...

2. Cannot Cast List as List    forums.oracle.com

public List getComments() throws RemoteException; public List getComments(int questionnaireId) throws RemoteException { return classLoader.getQuestionnaire(questionnaireId).getComments(); The compiler issues a Type mismatch: cannot convert from List to List Which I find perplexing as the compiler can assure that at the very least it is a List of Comment objects. Yes, however Java's generics work correctly to prevent you ...