java 如何获取本地图片的宽度and高度

public static int[] getFileWidthAndHeight(String imageUrl){
    File imageFile= new File(imageUrl);
    int[] arr = new int[2];
    try {
        ImageInputStream imageInputStream = ImageIO.createImageInputStream(imageFile);
        final Iterator<ImageReader> readers = ImageIO.getImageReaders(imageInputStream);
        if(readers.hasNext()){
            ImageReader reader = readers.next();
            reader.setInput(imageInputStream,true);
            int width = reader.getWidth(0);
            int height = reader.getHeight(0);
            arr[0] = width;
            arr[1] = height;
        }
    } catch (IOException e) {
        log.error("IOException "+e.getMessage(),e);
    }

    return  arr;
 /**
    首先是使用ImageIo根据图片文件获取图片的输入流,使用ImageIO 获取图片读取 ImageReader
    reader.setInput();然后就可以获取图片的宽度了和长度了...