Java从URL读取JPG文件

Question

public class Socket {
    public Socket() {
        try {
            URL url = new URL("http://images2.layoutsparks.com/1/56178/castle-stone-window-grey.jpg");
            InputStream in = url.openStream();
            BufferedInputStream bin = new BufferedInputStream(in); 


            ByteArrayOutputStream bout = new ByteArrayOutputStream(4096);
            byte[] okunan = new byte[4096];

            while(in.read()!= -1){
                bout.write(okunan, 0, in.read());

            }

        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

I got this error: Exception in thread "main" java.lang.IndexOutOfBoundsException at java.io.ByteArrayOutputStream.write(Unknown Source)

I want to read this jpeg file to in bytearrayoutputstream after then write to file.

Sory for my bad english..

Answer 1

尝试这个

BufferedImage img = ImageIO.read(new URL("http://images2.layoutsparks.com/1/56178/castle-stone-window-grey.jpg"));

Answer 2

Use the ImageIO API

BufferedImage img = ImageIO.read(new URL("http://images2.layoutsparks.com/1/56178/castle-stone-window-grey.jpg"));

ByteArrayOutputStream bout = new ByteArrayOutputStream();
ImageIO.write(img, "jpg", bout);

Check this and this for info

Answer 3

Do you mean something like

try {
        URL url = new URL("http://images2.layoutsparks.com/1/56178/castle-stone-window-grey.jpg");
        InputStream in = url.openStream();
        BufferedInputStream bin = new BufferedInputStream(in); 


        ByteArrayOutputStream bout = new ByteArrayOutputStream(4096);
        byte[] okunan = new byte[4096];

        while(in.read()!= -1){
            in.read(okunan);
            bout.write(okunan);

        }

    } catch (MalformedURLException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }

Answer 4

Use javax.imageio.ImageIO rather than simple InputStream of java.io package.

Have a look here, I think it will be helpful:

http://docs.oracle.com/javase/6/docs/api/javax/imageio/ImageIO.html