#vulnerable code 
                                @Override
    protected final void doGet(final SlingHttpServletRequest request, final SlingHttpServletResponse response) throws
            ServletException, IOException {

        // Get the transform names from the suffix
        final List<NamedImageTransformer> selectedNamedImageTransformers = getNamedImageTransformers(request);

        // Collect and combine the image transformers and their params
        final ValueMap imageTransformersWithParams = getImageTransformersWithParams(selectedNamedImageTransformers);

        final Image image = this.resolveImage(request);
        final String mimeType = this.getMimeType(request, image);
        Layer layer = this.getLayer(image);

        // Transform the image
        layer = this.transform(layer, imageTransformersWithParams);

        // Get the quality
        final double quality = this.getQuality(mimeType,
                imageTransformersWithParams.get(TYPE_QUALITY, EMPTY_PARAMS));

        response.setContentType(mimeType);
        layer.write(mimeType, quality, response.getOutputStream());
        response.flushBuffer();
    } 
                            #location 23 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                                @Override
    protected final void doGet(final SlingHttpServletRequest request, final SlingHttpServletResponse response) throws
            ServletException, IOException {

        // Get the transform names from the suffix
        final List<NamedImageTransformer> selectedNamedImageTransformers = getNamedImageTransformers(request);

        // Collect and combine the image transformers and their params
        final ValueMap imageTransformersWithParams = getImageTransformersWithParams(selectedNamedImageTransformers);

        final Image image = this.resolveImage(request);
        final String mimeType = this.getMimeType(request, image);
        Layer layer = this.getLayer(image);
        
        if (layer == null) {
            response.setStatus(SlingHttpServletResponse.SC_NOT_FOUND);
            return;
        }
        
        // Transform the image
        layer = this.transform(layer, imageTransformersWithParams);

        // Get the quality
        final double quality = this.getQuality(mimeType,
                imageTransformersWithParams.get(TYPE_QUALITY, EMPTY_PARAMS));

        response.setContentType(mimeType);
        layer.write(mimeType, quality, response.getOutputStream());
        response.flushBuffer();
    }