Uploaded image for project: 'JDK'
  1. JDK
  2. JDK-7086586

Inference producing null type argument

    XMLWordPrintable

Details

    • b08
    • generic
    • generic
    • Verified

    Backports

      Description

        When the inference algorithm determines that an inference variable is a subtype of a capture variable without a lower bound, it may choose "null" as the inference result. This is inconsistent with specified behavior.

        <T> Iterable<T> empty(Iterable<? super T> dummy) { return null; }
        {
        String s = empty((Iterable<?>) null).iterator().next(); // no error reported
        Number n = empty((Iterable<?>) null).iterator().next(); // no error reported
        Exception e = empty((Iterable<?>) null).iterator().next(); // no error reported
        empty((Iterable<?>) null).foo(); // error: can't find in Iterable<<null>>
        }

        Attachments

          Issue Links

            Activity

              People

                mcimadamore Maurizio Cimadamore
                dlsmith Dan Smith
                Votes:
                0 Vote for this issue
                Watchers:
                0 Start watching this issue

                Dates

                  Created:
                  Updated:
                  Resolved:
                  Imported:
                  Indexed: