I could be confused, but: I would expect class Map<K> and class Map<K extends @Nullable Object> to be equivalent. It appears that they're not. Here's some code that uses the longer version:
$ cat Map.java
import org.checkerframework.checker.nullness.qual.Nullable;
interface Set<E> {}
class Map<K extends @Nullable Object> {
Set<K> keySet = new KeySet();
class KeySet implements Set<K> {}
}
$ checker/bin/javac -processor org.checkerframework.checker.nullness.NullnessChecker Map.java
Map.java:6: error: [assignment.type.incompatible] incompatible types in assignment.
Set<K> keySet = new KeySet();
^
found : @Initialized @NonNull Map<K extends @Initialized @NonNull Object>.@Initialized @NonNull KeySet
required: @Initialized @NonNull Set<K extends @Initialized @Nullable Object>
1 errorHowever, if I tweak the class declaration to the "equivalent" shorter version, then the file compiles successfully. That's the behavior I would have expected in either case.
If I suppress the error, the .class files that I get for the long version is almost identical to that for the short version, according to javap -v. The only difference appears to be in the order of the RuntimeVisibleTypeAnnotations.
Source file and -version -verbose -AprintAllQualifiers output attached.
I could be confused, but: I would expect
class Map<K>andclass Map<K extends @Nullable Object>to be equivalent. It appears that they're not. Here's some code that uses the longer version:However, if I tweak the class declaration to the "equivalent" shorter version, then the file compiles successfully. That's the behavior I would have expected in either case.
If I suppress the error, the
.classfiles that I get for the long version is almost identical to that for the short version, according tojavap -v. The only difference appears to be in the order of theRuntimeVisibleTypeAnnotations.Source file and
-version -verbose -AprintAllQualifiersoutput attached.