Passing enum and EnumMap to a method

Generics are really new to me, and catching on has been a bit confusing.
The Sun tutorial is like a man page - you gotta read it a few times and
I've been too impatient to do so. I've actually been reading through
the java.util.EnumMap code to get a better grip on things. Since all
my googling didn't turn up an example of how to pass enums (and EnumMaps),
I figured I'd post it here for others if they have the same question.
Some of the recent threads on this topic were very helpful to me, but
I still needed to put it all together.

If anyone sees anything stupid (or any suggestions for improvement,
please let me know).

import java.util.*;

public class TestEnumMap {

  enum ThreeD { X, Y, Z }

  public static void main(String[] args) {

    double dval;

    EnumMap<ThreeD, Double> xyz =
                      new EnumMap<ThreeD, Double>(ThreeD.class);

    xyz.put(ThreeD.X, 5.0);
    xyz.put(ThreeD.Y, 10.0);
    xyz.put(ThreeD.Z, 15.0);
    System.out.println("Not Passed");
    for (ThreeD i : ThreeD.values()) {
      dval = xyz.get(i);
      System.out.println("" + i + ": " + dval);
    }

    printVals(xyz);
    printVals(ThreeD.class, xyz);
  }
  public static void printVals (EnumMap<ThreeD, Double> em) {
    System.out.println("Passed, but with just the EnumMap:");
    double dval;
    for (ThreeD i : ThreeD.values()) {
      dval = em.get(i);
      System.out.println("" + i + ": " + dval);
    }
  }

  public static <K extends Enum<K>> void printVals(Class<K> keyType,
                                             EnumMap<ThreeD, Double> em) {
    double dval;
    K[] keyUniverse = keyType.getEnumConstants();
    System.out.println("Everything Passed");
    for (int i=0; i<keyUniverse.length; i++) {
      dval = em.get(keyUniverse[i]);
      System.out.println("" + keyUniverse[i] + ": " + dval);
    }
  }
}

- Kurt