Example usage for com.vaadin.server VaadinServletResponse sendError

List of usage examples for com.vaadin.server VaadinServletResponse sendError

Introduction

In this page you can find the example usage for com.vaadin.server VaadinServletResponse sendError.

Prototype

public void sendError(int errorCode, String message) throws IOException;

Source Link

Document

Sends an error response to the client using the specified status code and clears the buffer.

Usage

From source file:annis.gui.requesthandler.BinaryRequestHandler.java

License:Apache License

public void sendResponse(VaadinSession session, VaadinRequest request, VaadinResponse pureResponse,
        boolean sendContent) throws IOException {
    if (!(pureResponse instanceof VaadinServletResponse)) {
        pureResponse.sendError(500, "Binary requests only work with servlets");
    }// w ww . j a  va 2s  .  c  o m

    VaadinServletResponse response = (VaadinServletResponse) pureResponse;

    Map<String, String[]> binaryParameter = request.getParameterMap();
    String toplevelCorpusName = binaryParameter.get("toplevelCorpusName")[0];
    String documentName = binaryParameter.get("documentName")[0];

    String mimeType = null;
    if (binaryParameter.containsKey("mime")) {
        mimeType = binaryParameter.get("mime")[0];
    }
    try {
        // always set the buffer size to the same one we will use for coyping, 
        // otherwise we won't notice any client disconnection
        response.reset();
        response.setCacheTime(-1);
        response.resetBuffer();
        response.setBufferSize(BUFFER_SIZE); // 4K

        String requestedRangeRaw = request.getHeader("Range");

        WebResource binaryRes = Helper.getAnnisWebResource().path("query").path("corpora")
                .path(urlPathEscape.escape(toplevelCorpusName)).path(urlPathEscape.escape(documentName))
                .path("binary");

        WebResource metaBinaryRes = Helper.getAnnisWebResource().path("meta").path("binary")
                .path(urlPathEscape.escape(toplevelCorpusName)).path(urlPathEscape.escape(documentName));

        // tell client that we support byte ranges
        response.setHeader("Accept-Ranges", "bytes");

        Preconditions.checkNotNull(mimeType, "No mime type given (parameter \"mime\"");

        AnnisBinaryMetaData meta = getMatchingMetadataFromService(metaBinaryRes, mimeType);
        if (meta == null) {
            response.sendError(404, "Binary file not found");
            return;
        }

        ContentRange fullRange = new ContentRange(0, meta.getLength() - 1, meta.getLength());

        ContentRange r = fullRange;
        try {
            if (requestedRangeRaw != null) {
                List<ContentRange> requestedRanges = ContentRange.parseFromHeader(requestedRangeRaw,
                        meta.getLength(), 1);

                if (!requestedRanges.isEmpty()) {
                    r = requestedRanges.get(0);
                }
            }

            long contentLength = (r.getEnd() - r.getStart() + 1);

            boolean useContentRange = !fullRange.equals(r);

            response.setContentType(meta.getMimeType());
            if (useContentRange) {
                response.setHeader("Content-Range", r.toString());
            }
            response.setContentLength((int) contentLength);
            response.setStatus(useContentRange ? 206 : 200);

            response.flushBuffer();
            if (sendContent) {
                try (OutputStream out = response.getOutputStream();) {
                    writeFromServiceToClient(r.getStart(), contentLength, binaryRes, out, mimeType);
                }
            }

        } catch (ContentRange.InvalidRangeException ex) {
            response.setHeader("Content-Range", "bytes */" + meta.getLength());
            response.sendError(416, "Requested range not satisfiable: " + ex.getMessage());
            return;
        }

    } catch (IOException ex) {
        log.warn("IOException in BinaryRequestHandler", ex);
        response.setStatus(500);
    } catch (ClientHandlerException | UniformInterfaceException ex) {
        log.error(null, ex);
        response.setStatus(500);
    }
}