在servlet 上输出图片

public void doGet(HttpServletRequest req, HttpServletResponse resp) throws IOException {
        // Get the absolute path of the image
        ServletContext sc = getServletContext();
        String filename = sc.getRealPath("image.gif"

);
    
        // Get the MIME type of the image
        String mimeType = sc.getMimeType(filename);
        if (mimeType == null) {
            sc.log("Could not get MIME type of "+filename);
            resp.setStatus(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
            return;
        }
    
        // Set content type
        resp.setContentType(mimeType);
    
        // Set content size
        File file = new File(filename);
        resp.setContentLength((int)file.length());
    
        // Open the file and output streams
        FileInputStream in = new FileInputStream(file);
        OutputStream out = resp.getOutputStream();
    
        // Copy the contents of the file to the output stream
        byte[] buf = new byte[1024

];
        int count = 0;
        while ((count = in.read(buf)) >= 0) {
            out.write(buf, 0, count);
        }
        in.close();
        out.close();
    }