如何获取“ Enum.CONSTANT”以返回某种类型（例如，颜色）？

Question

I want the field constants of my enum to return instances of the Color class instead of some constant values, is this possible in Java? I would like to avoid having to retrieve them through an accessor method. For example, this is the way I want to be able to use my enum:

Color color;
color = ExtendedColor.RED;
color = ExtendedColor.FOO;
color = ExtendedColor.BAZ;

---

import java.awt.*;

/**
 * Static utility enum for providing a much greater variety of Colors to choose from, some of which are not
 * included as constants in the Color class
 */
public enum ExtendedColor {
    RED(Color.RED),
    ORANGE(Color.ORANGE),
    YELLOW(Color.YELLOW),
    FOO(10, 20, 30),
    BAR(90, 90, 90),
    BAZ(30, 30, 30);

    private Color color;

    private ExtendedColor(Color color) {
        this.color = color;
    }

    private ExtendedColor(int r, int g, int b) {
        this.color = new Color(r, g, b);
    }
}

Answer 1

You can create a class with public static fields instead and access the fields directly ExtendedColor.COLOR1 .

import java.awt.*;

public class ExtendedColor {
    public static final Color COLOR1 = ...;
    public static final Color COLOR2 = ...;
    ...
}

Answer 2

One approach is given in the first answer. Another approach is to define a colorValue method in the ExtendedColor enum which returns the actual Color.

public enum ExtendedColor {
  ...
  public Color colorValue() {
    return color;
  }
}

And then you will have

Color color;
color = ExtendedColor.RED.colorValue();
color = ExtendedColor.FOO.colorValue();
color = ExtendedColor.BAZ.colorValue();