Method invoke

java/org/apache/catalina/valves/SemaphoreValve.java:221–256

Do concurrency control on the request using the semaphore. @param request The servlet request to be processed @param response The servlet response to be created @exception IOException if an input/output error occurs @exception ServletException if a servlet error occurs

(Request request, Response response)

     * @exception ServletException if a servlet error occurs
     */
    @Override
    public void invoke(Request request, Response response) throws IOException, ServletException {

        if (controlConcurrency(request, response)) {
            boolean shouldRelease = true;
            try {
                if (block) {
                    if (interruptible) {
                        try {
                            semaphore.acquire();
                        } catch (InterruptedException e) {
                            shouldRelease = false;
                            permitDenied(request, response);
                            return;
                        }
                    } else {
                        semaphore.acquireUninterruptibly();
                    }
                } else {
                    if (!semaphore.tryAcquire()) {
                        shouldRelease = false;
                        permitDenied(request, response);
                        return;
                    }
                }
                getNext().invoke(request, response);
            } finally {
                if (shouldRelease) {
                    semaphore.release();
                }
            }
        } else {
            getNext().invoke(request, response);
        }

    }


    /**