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
46
47
48
49
50
51
52
53
54
55
56
57
58
|
import org.checkerframework.checker.nullness.qual.*;
class CollectionsAnnotationsMin {
static class Collection1<E extends @Nullable Object> {
public void add(E elt) {
// :: error: (dereference.of.nullable)
elt.hashCode();
}
}
static class PriorityQueue1<E extends @NonNull Object> extends Collection1<E> {
public void add(E elt) {
// dereference allowed here
elt.hashCode();
}
}
// This is allowed, as "null" cannot be added to f1
static Collection1<? extends @Nullable Object> f1 = new PriorityQueue1<@NonNull Object>();
// :: error: (assignment.type.incompatible)
static Collection1<@Nullable Object> f2 = new PriorityQueue1<@NonNull Object>();
static void addNull1(Collection1<@Nullable Object> l) {
l.add(null);
}
// The upper bound on E is implicitly from Collection1
static <E extends @Nullable Object> void addNull2(Collection1<E> l) {
// :: error: (argument.type.incompatible)
l.add(null);
}
// The upper bound on E is implicitly from Collection1
static <E extends @Nullable Object> E addNull2b(Collection1<E> l, E p) {
// :: error: (argument.type.incompatible)
l.add(null);
return p;
}
static <@Nullable E extends @Nullable Object> void addNull3(Collection1<E> l) {
l.add(null);
}
static void bad() {
// :: error: (argument.type.incompatible)
addNull1(new PriorityQueue1<@NonNull Object>());
addNull2(new PriorityQueue1<@NonNull Object>());
addNull2b(new PriorityQueue1<@NonNull Object>(), new Object());
// :: error: (type.argument.type.incompatible)
addNull3(new PriorityQueue1<@NonNull Object>());
// :: error: (argument.type.incompatible)
f1.add(null);
}
}
|
