1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
|
import org.checkerframework.checker.nullness.qual.*;
import org.checkerframework.framework.qual.DefaultQualifier;
class WildcardSuper {
void testWithSuper(Cell<? super @NonNull String> cell) {
// TODO: Address comments. Since ? is explicitly lower bounded, I have made a judgment that
// it should be implicitly upper bounded.
// This is valid because the default upper bound is NonNull
// :: error: (dereference.of.nullable)
cell.get().toString();
}
// TODO: THIS SHOULD JUST ISSUE A WARNING, WHY WOULD PEOPLE WANT TO WRITE CONTRADICTING BOUNDS?
void testWithContradiction(Cell<? super @Nullable String> cell) {
// This is actually valid, because it's a contradiction, b/c
// the implicit upper bound is NonNull.
// We are free to do anything, as the method is not callable.
// TODO: test whether all calls of method fail.
// :: error: (dereference.of.nullable)
cell.get().toString();
}
@DefaultQualifier(Nullable.class)
void testWithImplicitNullable(@NonNull Cell<? super @NonNull String> cell) {
// :: error: (dereference.of.nullable)
cell.get().toString();
}
void testWithExplicitNullable(Cell<@Nullable ? extends @Nullable String> cell) {
// :: error: (dereference.of.nullable)
cell.get().toString();
}
void testWithDoubleNullable(Cell<@Nullable ? extends @Nullable String> cell) {
// :: error: (dereference.of.nullable)
cell.get().toString();
}
class Cell<E extends @Nullable Object> {
E get() {
throw new RuntimeException();
}
}
}
|
