Example demonstrating two approaches to implement boolean properties for enums

PropVsMeth.java

public final class PropVsMeth {

  /** We use boolean properties. */
  public enum Prop {

    A(true, true), B(true, false), C(false, true);

    private final boolean a;

    private final boolean b;

    Prop(boolean a, boolean b) {
      this.a = a;
      this.b = b;
    }

    public boolean isA() {
      return a;
    }

    public boolean isB() {
      return b;
    }
  }

  /** We use custom methods. */
  public enum Meth {
    A, B {
      @Override
      public boolean isB() {
        return false;
      }
    },
    C {

      @Override
      public boolean isA() {
        return false;
      }

    };

    public boolean isA() {
      return true;
    }

    public boolean isB() {
      return true;
    }
  }

  public static void main(String[] args) {
    System.out.println(Prop.class.getName());

    for (final Prop p : Prop.values()) {
      System.out.println(p + " a=" + p.isA() + " b=" + p.isB());
    }

    System.out.println(Meth.class.getName());

    for (final Meth p : Meth.values()) {
      System.out.println(p + " a=" + p.isA() + " b=" + p.isB());
    }
  }

}

Valve.java

package en;

/**
 * Valve state.
 */
public enum Valve {

    CLOSED(false, false), HALF_OPEN(true, false), FULL_OPEN(true, true);

    private final boolean open;
    private final boolean unlimited;

    private Valve(final boolean open, final boolean unlimited) {
        this.open = open;
        this.unlimited = unlimited;
    }

    /**
     * Check whether anything can pass.
     * 
     * @return if we allow at least a dribble.
     */
    public boolean isOpen() {
        return open;
    }

    /**
     * Check whether any traffic restrictions apply.
     * 
     * @return <code>true</code> if no restrictions apply.
     */
    public boolean isUnlimited() {
        return unlimited;
    }

}