从枚举中获取信息

Question

So i have Enum called Terrain

public enum Terrain {
    DIRT(4, "res/imgs/DirtTile.png"), GRASS(5, "res/imgs/GrassTile.png");

    private String filePath;
    private Image image;
    private boolean imageLoaded;
    private int value;

    Terrain(int val, String imagePath) {
        value = val;
        filePath = imagePath;
        imageLoaded = false;
    }

    public Image getImage() {
        if (!imageLoaded) {
            loadImage();
        }
        return image;

    }

    public void loadImage() {
        try {
            image = ImageIO.read(new File(filePath));
        } catch (IOException e) {
            System.err.println("Failed to load image!");
            e.printStackTrace();
        }
        imageLoaded = true;
    }
}

What I want is to be able to compare an int to the terrain value so that if it does equal, that terrain will be drawn to the screen.

I was thinking something like

if(int==Terrain.value){} 

But I'm not really sure how to go about this. If someone could help me out on this, I have an int array which i want to compare it to and if it does equal the value, I store that tile in a seperate image array.

EDIT:

For all those saying I should put a getValue() method, I want to compare my value to the all of the Enums stuff and if it does equal(to 4 for example, then I can set my image(to dirt).

I'm checking this in a different class.

Answer 1

you already have a method for getImage . Simply add a similar method for getValue

public int getValue() {
    return value;
}

then you can do

if (2 == Terrain.DIRT.getValue())
    //doSomething()

Answer 2

One possibility is add a static function to the Terrain enum as:

static Terrain getTerrainFor(int val)
{
   for (Terrain t : Terrain.values())
   {
      if (t.value() == val)
         return t;
   }

   return t;
}

call this (Terrain.getTerrainFor(int)) do logic

Answer 3

Add a getValue() method to the enum:

public int getValue() {
    return value;
}

Wherever you have an instance of the Terrain enum, call the getValue() method and do the comparison as you like:

Terrain t = Terrain.DIRT;
if (t.getValue() == 4) {
    System.our.println("The terrain value is 4!");
}

Answer 4

    enum Terrain{


    private int value;
    private static final Map<Integer, Terrain> terrainMap;

    static{
        terrainMap = new HashMap<Integer, Terrain>();
        for(Terrain type: values()){
            terrainMap.put(type.value, type);
        }
    }

    public static Terrain getTerrain(int value){
         return terrainMap.get(value);
    }

    }

Code that uses this enum:

Terrain terrain = Terrain.getTerrain(4);

switch(terrain){
   case DIRT:
   //draw dirt
}

Answer 5

In most cases like this, the best would be to get rid of the ints and use the enum type instead.

  Terrain terrain = somevalue;
  if( terrain == Terrain.DIRT ) {
    // do something
  }

Answer 6

If you want to get a Terrain from an int you can use java's built in valueOf(String) (This would be the easiest solution to your problem).

int i = 2;
Terrain t = Terrain.valueOf("" + i);

Of course you have to convert the int to a string (I used concatenation with an empty String for that.

EDIT: The best performing solution to your problem would be to use a static array, that contains the Terrain at the index, with a static method, that get's it out of there.