Color Class in Java

Question

I have a question regarding the awt Color class in Java.

I am currently using the class abbreviations such as Color.RED and Color.BLACK. I also have a list of three integers such as the following:

int var1 = 0
int var2 = 0
int var3 = 255

Is there a method to convert these integers into the appropriate Java Color name?

Answer 1

There is no way to do this with a single method in the Java core classes. However, you can fairly easily do this yourself in two ways.

First way

First, create a HashMap of Colors that contains all the colors you want:

HashMap<Color, String> colors = new HashMap<Color, String>();

colors.put(Color.BLACK,            "BLACK");
colors.put(Color.BLUE,             "BLUE");
colors.put(Color.CYAN,             "CYAN");
colors.put(Color.DARK_GRAY,        "DARK_GRAY");
colors.put(Color.GRAY,             "GRAY");
colors.put(Color.GREEN,            "GREEN");
colors.put(Color.LIGHT_GRAY,       "LIGHT_GRAY");
colors.put(Color.MAGENTA,          "MAGENTA");
colors.put(Color.ORANGE,           "ORANGE");
colors.put(Color.PINK,             "PINK");
colors.put(Color.RED,              "RED");
colors.put(Color.WHITE,            "WHITE");
colors.put(new Color(192, 0, 255), "PURPLE");
colors.put(new Color(0xBADA55),    "BADASS_GREEN");
colors.put(new Color(0, 0, 128),   "DARK_BLUE");

Then, create a new Color out of the RGB values you have:

Color color = new Color(var1, var2, var3);

Last, get the value in colors for the key color:

String colorName = colors.get(color);

Second way

This is potentially a less brittle way, but does have issues, and doesn't work as-is. You'll need to catch some exceptions, and maybe handle the case where a field isn't static and you can't just do f.get(null).

Create a new Color out of the RGB values you have:

Color color = new Color(var1, var2, var3);

Then

1. Get the Class object from the Color class with getClass().
2. Get the fields from that with getDeclaredFields().
3. Stream it using Arrays.stream()
4. Filter it by calling filter(), so it only contains all the enum constants that equal the color you made (there should be either one or zero).
5. Use toArray() to turn the stream into an array.
6. Get the first element of that array with [0]. This will throw an ArrayIndexOutOfBoundsException if there isn't a predefined color matching your color.
7. Get the name of that color with Enum's toString().

String colorName = Arrays.stream(Color.getClass().getDeclaredFields())
                         .filter(f -> f.get(null).equals(color))
                         .toArray()[0]
                         .toString();