Shortest Hello World?

Removing excess whitespace, is this the shortest hello world program one can make in Java?

Code:

---

enum X {
  X;
  X() {
    System.out.print("Hello World!");
  }
}

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Or without throwing an error:

Code:

---

enum X {
  X;
  X() {
    System.out.print("Hello World!");
    System.exit(0);
  }
}

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Any thoughts? Just curious if anyone can devise a smaller version. (I came up with the enum version after seeing one using static initializers.)