尝试实现我的Tilemap时，Java向我抛出错误'对于输入字符串：“”

Question

Right now I am facing a problem I just can't seem to find any help on the Internet. I am trying to implement my tilemap I made with Tiled into my Slick2D java project, but I can't get around this error code:

ERROR:For input string: ""
java.lang.NumberFormatException: For input string: ""
at java.lang.NumberFormatException.forInputString(Unknown Source)
at java.lang.Integer.parseInt(Unknown Source)
at java.lang.Integer.parseInt(Unknown Source)
at org.newdawn.slick.tiled.TiledMap$ObjectGroup.<init>(TiledMap.java:1008)
at org.newdawn.slick.tiled.TiledMap.load(TiledMap.java:688)
at org.newdawn.slick.tiled.TiledMap.<init>(TiledMap.java:106)
at org.newdawn.slick.tiled.TiledMap.<init>(TiledMap.java:90)
at simpleslickgame.SpielTest.init(SpielTest.java:36)
at org.newdawn.slick.AppGameContainer.setup(AppGameContainer.java:393)
at org.newdawn.slick.AppGameContainer.start(AppGameContainer.java:317)
at simpleslickgame.SpielTest.main(SpielTest.java:25)

Fri Dec 26 22:47:27 CET 2014 ERROR:Failed to parse tilemap
org.newdawn.slick.SlickException: Failed to parse tilemap
at org.newdawn.slick.tiled.TiledMap.load(TiledMap.java:695)
at org.newdawn.slick.tiled.TiledMap.<init>(TiledMap.java:106)
at org.newdawn.slick.tiled.TiledMap.<init>(TiledMap.java:90)
at simpleslickgame.SpielTest.init(SpielTest.java:36)
at org.newdawn.slick.AppGameContainer.setup(AppGameContainer.java:393)
at org.newdawn.slick.AppGameContainer.start(AppGameContainer.java:317)
at simpleslickgame.SpielTest.main(SpielTest.java:25)
Caused by: java.lang.NumberFormatException: For input string: ""
at java.lang.NumberFormatException.forInputString(Unknown Source)
at java.lang.Integer.parseInt(Unknown Source)
at java.lang.Integer.parseInt(Unknown Source)
at org.newdawn.slick.tiled.TiledMap$ObjectGroup.<init>(TiledMap.java:1008)
at org.newdawn.slick.tiled.TiledMap.load(TiledMap.java:688)
... 6 more

I just can't find a way to get my head around this. I am not working with any inputs which could end up in an input string. I just can't figure out what I'm doing wrong.

This is my code:

package simpleslickgame;

import org.newdawn.slick.AppGameContainer;
import org.newdawn.slick.BasicGame;
import org.newdawn.slick.GameContainer;
import org.newdawn.slick.Graphics;
import org.newdawn.slick.SlickException;
import org.newdawn.slick.tiled.TiledMap;

public class SpielTest extends BasicGame
{
public TiledMap map;

public SpielTest()
{
    super("Test");
}

public static void main(String[] arguments)
{
    try
    {
        AppGameContainer app = new AppGameContainer(new SpielTest());
        app.setDisplayMode(1000, 800, false);
        app.start();
    }
    catch (SlickException e)
    {
        e.printStackTrace();
    }
}

@Override
public void init(GameContainer container) throws SlickException
{
    map=new TiledMap("res/Slickesdingbruder.tmx");
}

@Override
public void update(GameContainer container, int delta) throws SlickException
{
}

public void render(GameContainer container, Graphics g) throws SlickException
{
    map.render(0, 0);
}
}

It might even be helpful to point me somewhere the problem could be, but I just can't find a connection beetween the code and the error.

Answer 1

Had same issue with an uncorrupted file, checked the Slick2D source. This error is caused by attempting to load a map with an object layer whose "width" and "height" properties are undefined or not parseable as Integers in its "objectgroup" XML tag (.tmx files are XML). The Slick2D version of Tiled's Java library expects them (it doesn't use them for anything as far as I can tell - the version I've got ignores map objects entirely in its rendering code) and the Tiled map editor wouldn't normally (if ever) define them - if you really need a bounding box for an object layer it's best computed after loading the map.

Hopefully this'll eventually be fixed, but the simplest workaround is to open up the .tmx file in a text editor and insert width="1" height="1" in every objectgroup tag. This could be automated by first loading the .tmx files into a String, doing a find() or regex search and replace and calling the TiledMap constructor with a " new ByteArrayInputStream(tmxString. getBytes(Charset.forName("UTF-8")) ".

Answer 2

@Dana Otken, the width="1" height="1" in the .tmx file is necessary, but I've noticed another factor. If you are indeed using Tiled, you MUST make sure EVERY object in every object layer has whole numbers for the following values: Width, Height, X location, and Y location. Here's the reason why: an int data type CANNOT handle decimals. You may recall, that's what the double data type is for. When slick (or lwjgl, I can't remember which) tries to use the parseInt method with a string input, it throws this error, and can't run. REMEMBER: Int can't hold a decimal value, and you are using the parseInt method.

PS You can't have a fraction of a pixel, so even if you did have a double value with an actual decimal, it wouldn't make sense because pixels can't be further divided.

Hope this helps!

A similar SO page here: https://gamedev.stackexchange.com/questions/93607/how-import-and-draw-a-tiledmap-with-slick2d/122051#122051