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import org.checkerframework.checker.nullness.qual.*;
class GenericsBounds4 {
class Collection1<E extends @Nullable Object> {
public void add(E elt) {
// :: error: (dereference.of.nullable)
elt.hashCode();
}
}
Collection1<? extends @Nullable Object> f1 = new Collection1<@NonNull Object>();
// :: error: (assignment.type.incompatible)
Collection1<@Nullable ? extends @Nullable Object> f2 = new Collection1<@NonNull Object>();
Collection1<@Nullable ? extends @Nullable Object> f3 = new Collection1<@Nullable Object>();
void bad() {
// This has to be forbidden, because f1 might refer to a
// collection that has NonNull as type argument.
// :: error: (argument.type.incompatible)
f1.add(null);
// This is forbidden by the Java type rules:
// f1.add(new Object());
// ok
f3.add(null);
}
}
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