抛出 javax.imageio.IIOException : Can't read input file! ，但我不知道为什么会这样？

Question

我想学习如何在 java 中制作 3D 图形，并找到了这段代码并研究了它，研究了它是如何工作的，我搜索了每个命令的工作原理。我运行了代码，它给了我一个错误，我真的不明白它是如何不起作用的。它应该将纹理放置在 map 中的墙壁上，但不会放置它们。我正在使用 eclipse 来运行代码。

import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;

public class Texture {
    public int[] pixels;
    private String loc;
    public final int SIZE;
        public Texture(String location, int size) {
        loc = location;
        SIZE = size;
        pixels = new int[SIZE * SIZE];
        load();
    }

    private void load() {
        try {
            BufferedImage image = ImageIO.read(new File(loc));
            int w = image.getWidth();
            int h = image.getHeight();
            image.getRGB(0, 0, w, h, pixels, 0, w);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public static Texture wood = new Texture("res/wood.png", 64);
    public static Texture brick = new Texture("res/redbrick.png", 64);
    public static Texture bluestone = new Texture("res/bluestone.png", 64);
    public static Texture stone = new Texture("res/greystone.png", 64);
}






import java.awt.Color;
import java.awt.Graphics;
import java.awt.image.BufferStrategy;
import java.awt.image.BufferedImage;
import java.awt.image.DataBufferInt;
import java.util.ArrayList;

import javax.swing.JFrame;

public class Game extends JFrame implements Runnable{

    private static final long serialVersionUID = 1L;
    public int mapWidth = 15;
    public int mapHeight = 15;
    private Thread thread;
    private boolean running;
    private BufferedImage image;
    public int[] pixels;
    public ArrayList<Texture> textures;
    public Camera camera;
    public Screen screen;
    public static int[][] map = 
        {
            {1,1,1,1,1,1,1,1,2,2,2,2,2,2,2},
            {1,0,0,0,0,0,0,0,2,0,0,0,0,0,2},
            {1,0,3,3,3,3,3,0,0,0,0,0,0,0,2},
            {1,0,3,0,0,0,3,0,2,0,0,0,0,0,2},
            {1,0,3,0,0,0,3,0,2,2,2,0,2,2,2},
            {1,0,3,0,0,0,3,0,2,0,0,0,0,0,2},
            {1,0,3,3,0,3,3,0,2,0,0,0,0,0,2},
            {1,0,0,0,0,0,0,0,2,0,0,0,0,0,2},
            {1,1,1,1,1,1,1,1,4,4,4,0,4,4,4},
            {1,0,0,0,0,0,1,4,0,0,0,0,0,0,4},
            {1,0,0,0,0,0,1,4,0,0,0,0,0,0,4},
            {1,0,0,0,0,0,1,4,0,3,3,3,3,0,4},
            {1,0,0,0,0,0,1,4,0,3,3,3,3,0,4},
            {1,0,0,0,0,0,0,0,0,0,0,0,0,0,4},
            {1,1,1,1,1,1,1,4,4,4,4,4,4,4,4}
        };

    public Game() {
        thread = new Thread(this);
        image = new BufferedImage(1920, 1080, BufferedImage.TYPE_INT_RGB);
        pixels = ((DataBufferInt)image.getRaster().getDataBuffer()).getData();
        textures = new ArrayList<Texture>();
        textures.add(Texture.wood);
        textures.add(Texture.brick);
        textures.add(Texture.bluestone);
        textures.add(Texture.stone);
        camera = new Camera(4.5, 4.5, 1, 0, 0, -.66);
        screen = new Screen(map, mapWidth, mapHeight, textures, 1920, 1080);
        addKeyListener(camera);
        setSize(1920, 1080);
        setResizable(true);
        setTitle("3D Engine");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setBackground(Color.black);
        setLocationRelativeTo(null);
        setVisible(true);
        start();
    }
    private synchronized void start() {
        running = true;
        thread.start();
    }
    public synchronized void stop() {
        running = false;
        try {
            thread.join();
        } catch(InterruptedException e) {
            e.printStackTrace();
        }
    }
    public void render() {
        BufferStrategy bs = getBufferStrategy();
        if(bs == null) {
            createBufferStrategy(3);
            return;
        }
        Graphics g = bs.getDrawGraphics();
        g.drawImage(image, 0, 0, image.getWidth(), image.getHeight(), null);
        bs.show();
    }
    public void run() {
        long lastTime = System.nanoTime();
        final double ns = 1000000000.0 / 60.0;//60 times per second
        double delta = 0;
        requestFocus();
        while(running) {
            long now = System.nanoTime();
            delta = delta + ((now-lastTime) / ns);
            lastTime = now;
            while (delta >= 1)//Make sure update is only happening 60 times a second
            {
                //handles all of the logic restricted time
                screen.update(camera, pixels);
                camera.update(map);
                delta--;
            }
            render();//displays to the screen unrestricted time
        }
    }
    public static void main(String [] args) {
        new Game();
    }
}

这是我每次运行代码时收到的错误消息。我尝试过使用不同的纹理位置，但不断收到相同的错误消息。

javax.imageio.IIOException: Can't read input file!
    at javax.imageio.ImageIO.read(ImageIO.java:1301)
    at Texture.load(Texture.java:20)
    at Texture.<init>(Texture.java:15)
    at Texture.<clinit>(Texture.java:29)
    at Game.<init>(Game.java:46)
    at Game.main(Game.java:104)
javax.imageio.IIOException: Can't read input file!
    at javax.imageio.ImageIO.read(ImageIO.java:1301)
    at Texture.load(Texture.java:20)
    at Texture.<init>(Texture.java:15)
    at Texture.<clinit>(Texture.java:30)
    at Game.<init>(Game.java:46)
    at Game.main(Game.java:104)
javax.imageio.IIOException: Can't read input file!
    at javax.imageio.ImageIO.read(ImageIO.java:1301)
    at Texture.load(Texture.java:20)
    at Texture.<init>(Texture.java:15)
    at Texture.<clinit>(Texture.java:31)
    at Game.<init>(Game.java:46)
    at Game.main(Game.java:104)
javax.imageio.IIOException: Can't read input file!
    at javax.imageio.ImageIO.read(ImageIO.java:1301)
    at Texture.load(Texture.java:20)
    at Texture.<init>(Texture.java:15)
    at Texture.<clinit>(Texture.java:32)
    at Game.<init>(Game.java:46)
    at Game.main(Game.java:104)

Answer 1

异常消息是不言自明的:无法读取 res/* 文件。

假设您已经有一个包含这些文件的 res 文件夹，该文件夹应该位于类路径中。如果没有将其放在类路径中或将 res/* 更改为绝对路径，例如C:\res\wood.png

javax.imageio.ImageIO 抛出异常:

public static BufferedImage read(File input) throws IOException {
        if (input == null) {
            throw new IllegalArgumentException("input == null!");
        }
        if (!input.canRead()) {
            throw new IIOException("Can't read input file!");
        }

File.canRead() 是(在 openJdk 1.8.0_192 上)

 public boolean canRead() {
        SecurityManager security = System.getSecurityManager();
        if (security != null) {
            security.checkRead(path);
        }
        if (isInvalid()) {
            return false;
        }
        return fs.checkAccess(this, FileSystem.ACCESS_READ);
    }

仅当路径无效或路径或文件没有读取访问权限时，input.canRead() 才会返回 false。如果在Linux中使用绝对路径，请递归地检查用户是否对该路径具有读取权限