Java 检查图片完整性代码

最近使用爬虫下载图片，遇到ctrl+C或者INT进行中断时，部分图片不能下载完整。因此需要筛选出这部分不完整图片的代码。

这里仅列出image/jpeg的例子：

import org.junit.Test;

import javax.imageio.ImageIO;
import javax.imageio.ImageReader;
import javax.imageio.stream.ImageInputStream;
import java.io.*;
import java.util.Iterator;

import static org.junit.Assert.assertEquals;

/**
 * Description: To do
 * 

 * Author : Adore Chen
 * Created: 2018-08-22
 */
public class ImageCheck {

    @Test
    public void testAll(){
        int count = 0;
        File dir = new File("/tmp/data/pics/");
        for(File file: dir.listFiles()){
            if(!isJPEG(file.getAbsolutePath())){
                System.out.println(file.getName());
                //file.delete();
                count++;
            }
        }
        assertEquals(0, count);
    }

    private Boolean isJPEG(String fileName) {
        boolean canRead = false;
        try(ImageInputStream iis = ImageIO.createImageInputStream(new File(fileName))){
            Iterator readers = ImageIO.getImageReadersByFormatName("jpg");
            while (readers.hasNext()) {
                ImageReader reader = readers.next();
                reader.setInput(iis);
                reader.read(0);
                canRead = true;
                break;
            }
        }catch (Exception e){

        }

        return canRead;
    }

}