如何使用 InputStream 转换或初始化 ImageInputStream？

Question

I am developing an image scraping application. I am getting URL

URL imageUrl = new URL(imageSource);

Then I'm creating an InputStream with this URL:

InputStream is = new URL(imageUrl.toString()).openStream();

After this I wanna create an ImageInputStream to determine ImageIO readers.

ImageInputStream iis = ??????

But I couldn't initialize this. Can I implement URL or InputStream for ImageInputStream?

Answer 1

this is what you are looking for:

ImageInputStream iis = ImageIO.createImageInputStream(is);

Answer 2

Better way is to use ImageIO.read(url) that returns BufferedReader

Answer 3

URL imageUrl = new URL(imageSource);
InputStream is = new URL(imageUrl.toString()).openStream();
ImageInputStream iis = ImageIO.createImageInputStream(is);
Iterator<ImageReader> iter = ImageIO.getImageReaders(iis);

if(!iter.hasNext())
    throw new RuntimeException("No readers found");
ImageReader reader = iter.next();

This is how you get your reader, or one of the ways of getting the reader. Hope it helps.