我知道一個關於java的相當數量,但是對於Slick2d和JSON是新手。我無法弄清楚爲什麼在嘗試加載.json映射文件時拋出異常。我使用的是eclipse,slick2d,lwjgl和json。我內置的地圖文件,它位於日食下的RES /地圖/ 這裏是堆棧跟蹤JSON和Eclipse - 爲什麼拋出異常?
java.lang.ClassCastException: java.lang.String cannot be cast to org.json.simple.JSONArray
at cardboard.world.World.load(World.java:33)
at cardboard.Engine.initStatesList(Engine.java:49)
at org.newdawn.slick.state.StateBasedGame.init(StateBasedGame.java:164)
at org.newdawn.slick.AppGameContainer.setup(AppGameContainer.java:393)
at org.newdawn.slick.AppGameContainer.start(AppGameContainer.java:317)
at cardboard.Engine.main(Engine.java:31)
這裏是執行代碼
try {
World.load("res/maps/world.json");
} catch (Exception e) {
System.err.println("Map does not exist");
System.exit(0);
}
這裏是世界級的
import java.io.FileReader;
import org.json.simple.JSONArray;
import org.json.simple.JSONObject;
import org.json.simple.parser.JSONParser;
import org.newdawn.slick.Image;
import org.newdawn.slick.SpriteSheet;
import cardboard.Resources;
public class World {
public static Image[][] solids;
public static int WIDTH;
public static int HEIGHT;
public static void load(String path) throws Exception {
JSONParser parser = new JSONParser();
Object obj = parser.parse(new FileReader(path));
JSONObject jObj = (JSONObject) obj;
JSONArray layers = (JSONArray) jObj.get("layers");
int amount = layers.size();
for (int i = 0; i < amount; i++) {
JSONObject layer = (JSONObject) layers.get(i);
String type = (String) layer.get("name");
if (type.equals("solids")) {
solids = parse((JSONArray)layer.get("data"));
} else if (type.equals("spawns")) {
// Spawn point code
}
}
}
private static Image[][] parse(JSONArray arr) {
Image[][] layer = new Image [WIDTH][HEIGHT];
int index;
for (int y = 0; y < WIDTH; y++) {
for (int x = 0; x < HEIGHT; x++) {
index = (int)((long)arr.get((y * WIDTH) + x));
layer[x][y] = getSpriteImage(index);
}
}
return layer;
}
private static Image getSpriteImage(int index) {
if (index == 0) return null;
index -= 1;
SpriteSheet sheet = Resources.getSprite("tileset");
//int vertical = sheet.getVerticalCount();
int horizontal = sheet.getHorizontalCount();
int y = (index/horizontal); //vert?
int x = (index % horizontal);
return sheet.getSubImage(x, y);
}
}
Eclipse沒有發生錯誤我剛剛收到我寫的「Map does not exist」的錯誤信息如果你可以看看,這將是超級!由於
情況下你需要Resources.java
package cardboard;
import java.util.HashMap;
import java.util.Map;
import org.newdawn.slick.Image;
import org.newdawn.slick.SlickException;
import org.newdawn.slick.Sound;
import org.newdawn.slick.SpriteSheet;
import cardboard.world.Tile;
public class Resources {
private static Map<String, Image> images;
private static Map<String, SpriteSheet> sprites;
private static Map<String, Sound> sounds;
public Resources() {
images = new HashMap<String, Image>();
sprites = new HashMap<String, SpriteSheet>();
sounds = new HashMap<String, Sound>();
try {
sprites.put("tileset", loadSprite("res/tileset.png", Tile.SMALL_SIZE, Tile.SMALL_SIZE));
} catch (SlickException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public static Image loadImage(String path) throws SlickException {
return new Image(path, false, Image.FILTER_NEAREST);
}
public static SpriteSheet loadSprite(String path, int tw, int th) throws SlickException {
return new SpriteSheet(loadImage(path), tw, th);
}
public static SpriteSheet getSprite(String getter) {
return sprites.get(getter);
}
public static Image getSpriteImage(String getter, int x, int y) {
return sprites.get(getter).getSubImage(x,y);
}
public static Image image(String getter) {
return sprites.get(getter);
}
public static Image getImage(String getter) {
return images.get(getter);
}
public static Sound getSound(String getter) {
return sounds.get(getter);
}
}
你會得到什麼例外?用'System.out.println'打印例如 – Enigo
只是打印出異常 –
請在你的問題中加入打印堆棧。 @ squirt706謝謝 –