Question

我已经链接了我要加载的文件，当我调试时，SpriteSheet构造函数显示路径变量存储了我指定的路径。当它试图运行image = ImageIO.read(SpriteSheet.class.getResourceAsStream(path));代码行时，它会因非法参数异常而崩溃。我唯一能想到的是错误的是我指定的文件不会加载，但我不知道为什么。

游戏课程：

package com.swainchris.twodgame;

import java.awt.BorderLayout;
import java.awt.Canvas;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.image.BufferStrategy;
import java.awt.image.BufferedImage;
import java.awt.image.DataBufferInt;

import javax.swing.JFrame;

import com.swainchris.twodgame.gfx.SpriteSheet;

public class Game extends Canvas implements Runnable {

private static final long serialVersionUID = 1L;
public static final int WIDTH = 160;
public static final int HEIGHT = WIDTH / 12 * 9;
public static final int SCALE = 3;
public static final String NAME = "2D Game";
public static boolean running = false;
private JFrame frame;
public int tickCount = 0;

private BufferedImage image = new BufferedImage(WIDTH, HEIGHT,    BufferedImage.TYPE_INT_RGB);
private int[] pixels = ((DataBufferInt)image.getRaster().getDataBuffer()).getData();

private SpriteSheet spriteSheet = new SpriteSheet("/SS.png");

public Game() {
    setMinimumSize(new Dimension(WIDTH * SCALE, HEIGHT * SCALE));
    setMaximumSize(new Dimension(WIDTH * SCALE, HEIGHT * SCALE));
    setPreferredSize(new Dimension(WIDTH * SCALE, HEIGHT * SCALE));

    frame = new JFrame(NAME);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setLayout(new BorderLayout());
    frame.add(this, BorderLayout.CENTER);
    frame.pack();
    frame.setResizable(false);
    frame.setLocationRelativeTo(null);
    frame.setVisible(true);
}


public synchronized void start() {
    running = true;
    new Thread(this).start();

}



public synchronized void stop() {
    running = false;
}



public void tick(){ 
    tickCount++;

    for(int i = 0; i < pixels.length; i++){
        pixels[i] = i - tickCount;
    }
}



public void render(){   
    BufferStrategy bs = getBufferStrategy();
    if(bs==null){
        createBufferStrategy(3);
        return;
    }

    Graphics g = bs.getDrawGraphics();


    g.drawImage(image,0,0,getWidth(),getHeight(),null);

    g.setColor(Color.BLACK);
    g.fillOval(50,50,50,50);

    g.dispose();
    bs.show();
}


public void run() {

    long lastTime = System.nanoTime();
    double nsPerTick = 1000000000D/60D;
    int ticks = 0;
    int frames = 0;
    long lastTimer = System.currentTimeMillis();
    double delta = 0;

    while(running){

        long now = System.nanoTime();
        delta += (now - lastTime) / nsPerTick;
        lastTime = now;
        boolean shouldRender = true;

        while(delta >= 1){
            ticks++;
            tick(); 
            delta--;
        }

        try {
            Thread.sleep(1);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

        if(shouldRender){
        frames++;
        render();
        }


        if(System.currentTimeMillis() - lastTimer >= 1000){
            lastTimer += 1000;
            frame.setTitle("2D Game!   FPS: " + frames + " UPS: " + ticks);
            frames = 0;
            ticks = 0;  
        }
    }
}

public static void main(String[] args) {

    new Game().start();

}

}

SpriteSheet类：

package com.swainchris.twodgame.gfx;

import java.awt.image.BufferedImage;
import java.io.IOException;

import javax.imageio.ImageIO;

public class SpriteSheet {

public String path;
public int width;
public int height;

public int[] pixels;

public SpriteSheet(String path){
    BufferedImage image = null;

    try {
        image = ImageIO.read(SpriteSheet.class.getResourceAsStream(path));
    } catch (IOException e) {
        e.printStackTrace();
    }

    if(image == null){
        return; 
    }

    this.path = path;
    this.width = image.getWidth();
    this.height = image.getHeight();

    pixels = image.getRGB(0,0,width,height,null,0,width);

    for(int i = 0; i < pixels.length; i++){
        pixels[i] = (pixels[i] & 0xff)/64;
    }

    for(int i = 0; i<8; i++){
        System.out.println(pixels[i]);
    }
}

}

错误：

Exception in thread "main" java.lang.IllegalArgumentException: input == null!
at javax.imageio.ImageIO.read(Unknown Source)
at com.swainchris.twodgame.gfx.SpriteSheet.<init>(SpriteSheet.java:20)
at com.swainchris.twodgame.Game.<init>(Game.java:30)
at com.swainchris.twodgame.Game.main(Game.java:137)

Answer 1

现在，我所做的就是将所有代码复制到新的项目文件中。除了项目的名称之外，没有任何改变。不知道为什么会这样，但确实如此。

尝试加载精灵表时抛出非法参数异常

1 个答案: