$ scalac -version
Scala compiler version 2.10.0-20120423-023931-3b61d19cdc -- Copyright 2002-2011, LAMP/EPFL

$ cat MyAnnotation.java
public @interface MyAnnotation { String value(); }

$ scalac -Ystop-after:typer -Xprint:typer MyAnnotation.java
[[syntax trees at end of typer]]// Scala source: MyAnnotation.java
package <empty> {
  object MyAnnotation extends  {
    def <init>() = _
  };
  class MyAnnotation extends scala.Annotation with _root_.java.lang.annotation.Annotation with scala.ClassfileAnnotation {
    def <init>(x$1: String) = _;
    def <init>() = _;
    def value(): String
  }
}

$ javac MyAnnotation.java

$ scala
Welcome to Scala version 2.10.0-20120423-023931-3b61d19cdc (Java HotSpot(TM) 64-Bit Server VM, Java 1.6.0_26).
Type in expressions to have them evaluated.
Type :help for more information.

scala> :power
** Power User mode enabled - BEEP WHIR GYVE **
** :phase has been set to 'typer'.          **
** scala.tools.nsc._ has been imported      **
** global._, definitions._ also imported    **
** Try  :help, :vals, power.<tab>           **

scala> ?[MyAnnotation].info

res0: $r.power.intp.global.Type = 
scala.annotation.Annotation
        with scala.annotation.ClassfileAnnotation
        with java.lang.annotation.Annotation {
  def value(): String
  def <init>(): MyAnnotation
}

  def <init>(): MyAnnotation

  def <init>(x$1: String) = _; // this is the default constructor
def <init>() = _;