获取图片文件尺寸效率比较

String srcImgPath = "C:/Users/Administrator/Desktop/4aff7849jw1evg4ud63awj24qo35cx6p.jpg";      
File file = new File(srcImgPath);


long beginTime = new Date().getTime();
BufferedImage sourceImg = ImageIO.read(new FileInputStream(file));
int new_w = sourceImg.getWidth();
int new_h = sourceImg.getHeight();
System.out.println(new_w);
System.out.println(new_h);
long endTime = new Date().getTime();
System.out.println("使用[BufferedImage]获取图片尺寸耗时：[" + (endTime - beginTime)+"]ms");

beginTime = new Date().getTime();
try {
Iterator<ImageReader> readers = ImageIO.getImageReadersByFormatName(srcImgPath.substring(srcImgPath.lastIndexOf(".") + 1));
ImageReader reader = (ImageReader) readers.next();
ImageInputStream iis = ImageIO.createImageInputStream(file);
reader.setInput(iis, true);
endTime = new Date().getTime();
System.out.println("width:" + reader.getWidth(0));
System.out.println("height:" + reader.getHeight(0));
} catch (IOException e) {
e.printStackTrace();
}

System.out.println("使用[ImageReader]获取图片尺寸耗时：[" + (endTime - beginTime)+"]ms");