javax.imageio.IIOException: Can't read input file!

昨天晚上做一个java分析图片RGB值的案例的时候，copy了网上的代码，在运行代码后出现如下问题：

检查了半天，也转译了路径，发现都是不行，这个文件读取不到，今天早上又在网上查了下，试了半天，最后使用加载器解决:

package com.pic;

import java.awt.AWTException;
import java.awt.Dimension;
import java.awt.Rectangle;
import java.awt.Robot;
import java.awt.Toolkit;
import java.awt.image.BufferedImage;
import java.io.File;
import java.net.URL;

import javax.imageio.ImageIO;  

public class PictureResolve {
	/** 
     * 读取一张图片的RGB值 
     * @throws Exception 
     */  
    public void getImagePixel(String image) throws Exception {  
    	//先获取路径的URL
    	URL imageResource = this.getClass().getResource(image);
        int[] rgb = new int[3]; 
        //根据URL获取路径，生成file对象
        File file = new File(imageResource.getPath()); 
        BufferedImage bi = null;  
        try {
			bi = ImageIO.read(file);
		} catch (Exception e) {
			e.printStackTrace();
		}  
        int width = bi.getWidth();  
        int height = bi.getHeight();  
        int minx = bi.getMinX();  
        int miny = bi.getMinY();  
        System.out.println("width=" + width + ",height=" + height + ".");  
        System.out.println("minx=" + minx + ",miniy=" + miny + ".");  
       // Map RGBMap = new HashMap<>();
        for (int i = minx; i < width; i++) {  
            for (int j = miny; j < height; j++) {  
                int pixel = bi.getRGB(i, j); // 下面三行代码将一个数字转换为RGB数字  
                rgb[0] = (pixel & 0xff0000) >> 16;  
                rgb[1] = (pixel & 0xff00) >> 8;  
                rgb[2] = (pixel & 0xff);
                
                System.out.println("i=" + i + ",j=" + j + ":(" + rgb[0] + ","  
                        + rgb[1] + "," + rgb[2] + ")");  
            }  
        }  
    }  
  
    /** 
     * 返回屏幕色彩值 
     *  
     * @param x 
     * @param y 
     * @return 
     * @throws AWTException 
     */  
    public int getScreenPixel(int x, int y) throws AWTException { // 函数返回值为颜色的RGB值。  
        Robot rb = null; // java.awt.image包中的类，可以用来抓取屏幕，即截屏。  
        rb = new Robot();  
        Toolkit tk = Toolkit.getDefaultToolkit(); // 获取缺省工具包  
        Dimension di = tk.getScreenSize(); // 屏幕尺寸规格  
        System.out.println(di.width);  
        System.out.println(di.height);  
        Rectangle rec = new Rectangle(0, 0, di.width, di.height);  
        BufferedImage bi = rb.createScreenCapture(rec);  
        int pixelColor = bi.getRGB(x, y);  
  
        return 16777216 + pixelColor; // pixelColor的值为负，经过实践得出：加上颜色最大值就是实际颜色值。  
    }  
  
    /** 
     * @param args 
     */  
    public static void main(String[] args) throws Exception {  
        int x = 0;  
        PictureResolve pr = new PictureResolve();  
        x = pr.getScreenPixel(100, 345);  
        System.out.println(x + " - ");  
        pr.getImagePixel("aaa.jpg");  
    }  
}

同过加载器，完美解决URL imageResource = this.getClass().getResource(image);