Java Code Examples for com.vaadin.flow.server.VaadinSession#unlock()

/**
 * Handle sending for a stream resource request.
 *
 * @param session        session for the request
 * @param request        request to handle
 * @param response       response object to which a response can be written.
 * @param streamResource stream resource that handles data writer
 * @throws IOException if an IO error occurred
 */
public void handleRequest(VaadinSession session, VaadinRequest request,
                          VaadinResponse response, StreamResource streamResource)
    throws IOException {

    StreamResourceWriter writer;
    session.lock();
    try {

        ServletContext context = ((VertxVaadinRequest) request).getService().getServletContext();
        response.setContentType(streamResource.getContentTypeResolver()
            .apply(streamResource, context));
        response.setCacheTime(streamResource.getCacheTime());
        writer = streamResource.getWriter();
        if (writer == null) {
            throw new IOException(
                "Stream resource produces null input stream");
        }
    } finally {
        session.unlock();
    }
    try (OutputStream outputStream = response.getOutputStream()) {
        writer.accept(outputStream, session);
    }
}
 

private long updateProgress(VaadinSession session,
                            StreamVariable streamVariable,
                            StreamingProgressEventImpl progressEvent, long lastStreamingEvent,
                            int bytesReadToBuffer) {
    long now = System.currentTimeMillis();
    // to avoid excessive session locking and event storms,
    // events are sent in intervals, or at the end of the file.
    if (lastStreamingEvent + getProgressEventInterval() <= now
        || bytesReadToBuffer <= 0) {
        session.lock();
        try {
            streamVariable.onProgress(progressEvent);
        } finally {
            session.unlock();
        }
    }
    return now;
}
 

@Override
public boolean handleRequest(VaadinSession session, VaadinRequest request,
        VaadinResponse response) throws IOException {
    // Use a copy to avoid ConcurrentModificationException
    session.lock();
    List<RequestHandler> requestHandlers;
    try {
        requestHandlers = new ArrayList<>(session.getRequestHandlers());
    } finally {
        session.unlock();
    }
    for (RequestHandler handler : requestHandlers) {
        if (handler.handleRequest(session, request, response)) {
            return true;
        }
    }
    // If not handled
    return false;
}
 

/**
 * Streams content from a multipart request to given StreamVariable.
 * <p>
 * This method takes care of locking the session as needed and does not
 * assume the caller has locked the session. This allows the session to be
 * locked only when needed and not when handling the upload data.
 *
 * @param session
 *            The session containing the stream variable
 * @param request
 *            The upload request
 * @param response
 *            The upload response
 * @param streamReceiver
 *            the receiver containing the destination stream variable
 * @param owner
 *            The owner of the stream
 * @throws IOException
 *             If there is a problem reading the request or writing the
 *             response
 */
protected void doHandleMultipartFileUpload(VaadinSession session,
        VaadinRequest request, VaadinResponse response,
        StreamReceiver streamReceiver, StateNode owner) throws IOException {
    boolean success = false;
    try {
        if (hasParts(request)) {
            success = handleMultipartFileUploadFromParts(session, request,
                    streamReceiver, owner);
        } else {
            success = handleMultipartFileUploadFromInputStream(session,
                    request, streamReceiver, owner);
        }
    } catch (Exception exception) {
        session.lock();
        try {
            session.getErrorHandler().error(new ErrorEvent(exception));
        } finally {
            session.unlock();
        }
    }
    sendUploadResponse(response, success);
}
 

private long updateProgress(VaadinSession session,
        StreamVariable streamVariable,
        StreamingProgressEventImpl progressEvent, long lastStreamingEvent,
        int bytesReadToBuffer) {
    long now = System.currentTimeMillis();
    // to avoid excessive session locking and event storms,
    // events are sent in intervals, or at the end of the file.
    if (lastStreamingEvent + getProgressEventInterval() <= now
            || bytesReadToBuffer <= 0) {
        session.lock();
        try {
            streamVariable.onProgress(progressEvent);
        } finally {
            session.unlock();
        }
    }
    return now;
}
 

/**
 * Handle reception of incoming stream from the client.
 *
 * @param session        The session for the request
 * @param request        The request to handle
 * @param response       The response object to which a response can be written.
 * @param streamReceiver the receiver containing the destination stream variable
 * @param uiId           id of the targeted ui
 * @param securityKey    security from the request that should match registered stream
 *                       receiver id
 * @throws IOException if an IO error occurred
 */
public void handleRequest(VaadinSession session, VaadinRequest request,
                          VaadinResponse response, StreamReceiver streamReceiver, String uiId,
                          String securityKey) throws IOException {
    StateNode source;

    session.lock();
    try {
        String secKey = streamReceiver.getId();
        if (secKey == null || !secKey.equals(securityKey)) {
            getLogger().warn(
                "Received incoming stream with faulty security key.");
            return;
        }

        UI ui = session.getUIById(Integer.parseInt(uiId));
        UI.setCurrent(ui);

        source = streamReceiver.getNode();

    } finally {
        session.unlock();
    }

    try {
        Set<FileUpload> fileUploads = ((VertxVaadinRequest) request).getRoutingContext().fileUploads();
        if (!fileUploads.isEmpty()) {
            doHandleMultipartFileUpload(session, request, response, fileUploads, streamReceiver, source);
        } else {
            // if boundary string does not exist, the posted file is from
            // XHR2.post(File)
            doHandleXhrFilePost(session, request, response, streamReceiver,
                source, getContentLength(request));
        }
    } finally {
        UI.setCurrent(null);
    }
}
 

private void handleFileUploadValidationAndData(VaadinSession session,
                                               InputStream inputStream, StreamReceiver streamReceiver,
                                               String filename, String mimeType, long contentLength,
                                               StateNode node) throws UploadException {
    session.lock();
    try {
        if (node == null) {
            throw new UploadException(
                "File upload ignored because the node for the stream variable was not found");
        }
        if (!node.isAttached()) {
            throw new UploadException("Warning: file upload ignored for "
                + node.getId() + " because the component was disabled");
        }
    } finally {
        session.unlock();
    }
    try {
        // Store ui reference so we can do cleanup even if node is
        // detached in some event handler
        boolean forgetVariable = streamToReceiver(session, inputStream,
            streamReceiver, filename, mimeType, contentLength);
        if (forgetVariable) {
            cleanStreamVariable(session, streamReceiver);
        }
    } catch (Exception e) {
        session.lock();
        try {
            session.getErrorHandler().error(new ErrorEvent(e));
        } finally {
            session.unlock();
        }
    }
}
 

private void cleanStreamVariable(VaadinSession session,
                                 StreamReceiver streamReceiver) {
    session.lock();
    try {
        session.getResourceRegistry().unregisterResource(streamReceiver);
    } finally {
        session.unlock();
    }
}
 

/**
 * Handle reception of incoming stream from the client.
 *
 * @param session
 *            The session for the request
 * @param request
 *            The request to handle
 * @param response
 *            The response object to which a response can be written.
 * @param streamReceiver
 *            the receiver containing the destination stream variable
 * @param uiId
 *            id of the targeted ui
 * @param securityKey
 *            security from the request that should match registered stream
 *            receiver id
 * @throws IOException
 *             if an IO error occurred
 */
public void handleRequest(VaadinSession session, VaadinRequest request,
        VaadinResponse response, StreamReceiver streamReceiver, String uiId,
        String securityKey) throws IOException {
    StateNode source;

    session.lock();
    try {
        String secKey = streamReceiver.getId();
        if (secKey == null || !secKey.equals(securityKey)) {
            getLogger().warn(
                    "Received incoming stream with faulty security key.");
            return;
        }

        UI ui = session.getUIById(Integer.parseInt(uiId));
        UI.setCurrent(ui);

        source = streamReceiver.getNode();

    } finally {
        session.unlock();
    }

    try {
        if (isMultipartUpload(request)) {
            doHandleMultipartFileUpload(session, request, response,
                    streamReceiver, source);
        } else {
            // if boundary string does not exist, the posted file is from
            // XHR2.post(File)
            doHandleXhrFilePost(session, request, response, streamReceiver,
                    source, getContentLength(request));
        }
    } finally {
        UI.setCurrent(null);
    }
}
 

private boolean handleFileUploadValidationAndData(VaadinSession session,
        InputStream inputStream, StreamReceiver streamReceiver,
        String filename, String mimeType, long contentLength,
        StateNode node) throws UploadException {
    session.lock();
    try {
        if (node == null) {
            throw new UploadException(
                    "File upload ignored because the node for the stream variable was not found");
        }
        if (!node.isAttached()) {
            throw new UploadException("Warning: file upload ignored for "
                    + node.getId() + " because the component was disabled");
        }
    } finally {
        session.unlock();
    }
    try {
        // Store ui reference so we can do cleanup even if node is
        // detached in some event handler
        Pair<Boolean, UploadStatus> result = streamToReceiver(session,
                inputStream, streamReceiver, filename, mimeType,
                contentLength);
        if (result.getFirst()) {
            cleanStreamVariable(session, streamReceiver);
        }
        return result.getSecond() == UploadStatus.OK;
    } catch (Exception e) {
        session.lock();
        try {
            session.getErrorHandler().error(new ErrorEvent(e));
        } finally {
            session.unlock();
        }
    }
    return false;
}
 

private void cleanStreamVariable(VaadinSession session,
        StreamReceiver streamReceiver) {
    session.lock();
    try {
        session.getResourceRegistry().unregisterResource(streamReceiver);
    } finally {
        session.unlock();
    }
}
 

private void accessSynchronously(Command command,
        SerializableRunnable detachHandler) {

    Map<Class<?>, CurrentInstance> old = null;

    VaadinSession session = getSession();

    if (session == null) {
        handleAccessDetach(detachHandler);
        return;
    }

    VaadinService.verifyNoOtherSessionLocked(session);

    session.lock();
    try {
        if (getSession() == null) {
            // UI was detached after fetching the session but before we
            // acquired the lock.
            handleAccessDetach(detachHandler);
            return;
        }
        old = CurrentInstance.setCurrent(this);
        command.execute();
    } finally {
        session.unlock();
        if (old != null) {
            CurrentInstance.restoreInstances(old);
        }
    }

}
 

/**
 * Get registry by handing the session lock correctly.
 *
 * @param session target vaadin session
 * @return session route registry for session if exists or new.
 */
private SessionRouteRegistry getRegistry(VaadinSession session) {
    try {
        session.lock();
        return (SessionRouteRegistry) SessionRouteRegistry
                .getSessionRegistry(session);
    } finally {
        session.unlock();
    }
}