While exploring adding covariant overrides for Buffer classes, it was discovered that javac is not making synthetic methods for covariant overrides match the finality of the covariant method.

Simple illustration:

  public class Test {
      public Object foo() { return null; }
  }
  public class TestSub extends Test {
      public final String foo() { return null; }
  }

Yields (javap output):

  public class Test {
    public Test();
    public java.lang.Object foo();
  }
  public class TestSub extends Test {
    public TestSub();
    public final java.lang.String foo();
    public java.lang.Object foo(); // <- not final?!
  }

reported in compiler-dev: http://mail.openjdk.java.net/pipermail/compiler-dev/2014-April/008732.html