HTTP Servlet请求重定向到另一个URL并在Java中自动登录

Question

I'm developing a HTTP filter that redirects to another URL when some image is requested, but the other URL that the new image is, needs authentication. I'm using AEM DAM to store all images. So when the code requests an image locally, the code needs to redirect to DAM and log in, but I can't log in using the code as it is implemented:

@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
        throws IOException, ServletException {

    HttpServletRequest req = (HttpServletRequest) request;
    // ==> /images/path/my-image.png
    // ==> /path1/path2/image.pngs
    String servletPath = req.getServletPath();

    // The path to the root directory of the webapp (WebContent)
    //String realRootPath = request.getServletContext().getRealPath("");
    String realRootPath = "http://localhost:4502/crx/de/index.jsp#/content/dam/";

    // Real path of Image.
    String imageRealPath = realRootPath + servletPath;

    System.out.println("imageRealPath = " + imageRealPath);

    File file = new File(imageRealPath);

    // Check image exists.
    if (file.exists()) {
        // Go to the next element (filter or servlet) in chain
        chain.doFilter(request, response);
    } else if (!servletPath.equals(this.notFoundImage)) {
        // Redirect to 'image not found' image.
        HttpServletResponse resp = (HttpServletResponse) response;
        // ==> /ServletFilterTutorial + /images/image-not-found.png
        resp.sendRedirect(req.getContextPath()+ this.notFoundImage);
    }
}

Answer 1

AEM supports basic authentication. So, while calling DAM asset URL, then pass username/password.

byte[] authEncBytes = Base64.encodeBase64("admin:admin".getBytes());
String authStringEnc = new String(authEncBytes);         
URL url = new URL("http://localhost:4502/content/dam/myassets/test.jpg");
        URLConnection urlConnection = url.openConnection();
        urlConnection.setRequestProperty("Authorization", "Basic " + 
         authStringEnc);
        InputStream is = urlConnection.getInputStream();