Input == null with using ImageIO.read

Question

Here is the code that I am using:

/**
 * This method loads an image
 * 
 * @param path - path of the image
 * 
 * 
 */
public static BufferedImage loadImage(String path) {
    try {
        return ImageIO.read(ImageLoader.class.getClass().getResourceAsStream(path));
    } catch (IOException e) {
        e.printStackTrace();
        System.exit(1);
    }
    return null;
}

Here is the error:

Exception in thread "Thread-2" java.lang.IllegalArgumentException: input == null!
at javax.imageio.ImageIO.read(Unknown Source)
at io.deadspace.graphics.ImageLoader.loadImage(ImageLoader.java:19)
at io.deadspace.graphics.asset.assets.EntityAssets.initEntityAssets(EntityAssets.java:15)
at io.deadspace.graphics.asset.Assets.init(Assets.java:37)
at io.deadspace.Game.init(Game.java:73)
at io.deadspace.Game.run(Game.java:127)
at java.lang.Thread.run(Unknown Source)

I recently re-did the way I loaded images into my game, it worked fine before, but now, it doesn't work anymore. I've tried both getResource and getResourceAsStream.

Here are some examples of how I am loading the images:

public void initEntityAssets() {
    sheet = new SpriteSheet(ImageLoader.loadImage("res/textures/sheet.png"));

    wood = sheet.crop(width, height, width, height);
    tree = sheet.crop(0, 0, width, height * 2);
    rock = sheet.crop(0, height * 2, width, height);
    rockDropItem = sheet.crop(1, height * 2, width, height);

}

public void initHotbarAssets() {
    sheet = new SpriteSheet(ImageLoader.loadImage("res/textures/sheet.png"));

    hotbar = sheet.crop(0, height * 4, width, height);
    hotbar_selected = sheet.crop(0, height * 5, width, height);
}

Also consider loading image once and reusing it. – M. Prokhorov Nov 24 '17 at 16:32 — M. Prokhorov, Nov 24 '17 at 16:32

score 0 · Answer 1 · answered Nov 24 '17 at 16:31

0

your path should be relative to the class path root, so it should be

sheet = new SpriteSheet(ImageLoader.loadImage("/res/textures/sheet.png"));

answered Nov 24 '17 at 16:31

Ayo K

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score 0 · Answer 2 · answered Nov 24 '17 at 16:33

0

If res is inside the java folder of the project structure you must use:

 ImageLoader.class.getClassLoader().getResourceAsStream(path)

The reason is described here:

Difference between getClass().getClassLoader().getResource() and getClass.getResource()?

Another solution instead of using getClassLoader() is adding a slash in the path so it begin searching in the root path.

/res/something

instead of res/something

answered Nov 24 '17 at 16:33

Marcos Vasconcelos

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this fixed it! Thank you very much!! – AROD2003 Nov 25 '17 at 00:24
please upvote or accept the answer – Marcos Vasconcelos Nov 25 '17 at 00:25

Input == null with using ImageIO.read

2 Answers2