Method compatibility not checked during cast conversion

Name: tb29552 Date: 08/15/97


The following illustrates that javac's implementation of cast
conversion is incorrect. The cast should be a compile-time error because I and
J contain methods with the same signature but different return types; the
reference comparison should be wrong for the same reason (since ==/!= must check
for cast convertibility first).

interface I {
    void f ();
}

interface J {
    int f ();
}

public class C {
    {
        I i = null;
        J j = (J)i; // should be an error according to 5.5

        if (i == j) // should be an error according to 15.20.3
            System.out.println("It is allowed after all.");
    }
}
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