Image generator for minecraft biome map

/**
* This is some code that you can put into your plugin to generate a biome map, similar to the ones in
* the tutorial.
*/
public void onEnable() {
    BufferedImage image = new BufferedImage(1920, 1080, BufferedImage.TYPE_INT_RGB);
    BiomeGenerator gen = new BiomeGenerator(getServer().getWorld("world"));

    for (int x = 0; x < image.getWidth(); x++) {
        for (int z=0; z < image.getHeight(); z++) {
            HashMap<Biomes, Double> biomes = gen.getBiomes(x, z);
            image.setRGB(x, z, getRbg(biomes));
        }
    }

    try {
        ImageIO.write(image, "png", new File(getDataFolder().getAbsoluteFile().toString() + File.pathSeparator + "image.png"));
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
}
private int getRbg(HashMap<Biomes, Double> biomes) {
    int color = 0;

    double maxNoiz = 0.0;
    for (Biomes biome : biomes.keySet()) {
        if (biomes.get(biome) > maxNoiz) color = getBiomeColor(biome);
    }

    return color;
}

private int getBiomeColor(Biomes biome) {
    switch(biome) {
    case DESERT: return Color.ORANGE.getRGB();
    case FOREST: return Color.GREEN.darker().getRGB();
    case PLAINS: return Color.GREEN.getRGB();
    case SWAMP:  return Color.GREEN.darker().darker().getRGB();
    case HILLS:  return Color.GREEN.brighter().getRGB();
    default:     return Color.white.getRGB();
    }
}