callCount.addAndGet(10);
            }
        };

        // Add first listener
        jobExecutor.addShutdownListener(listener1);
        assertEquals(listener1, jobExecutor.shutdownListener);

        // Replace with second listener
        jobExecutor.addShutdownListener(listener2);
        assertEquals(listener2, jobExecutor.shutdownListener);

        // Verify only second listener is called

        // Add first listener
        TestShutdownListener listener1 = new TestShutdownListener();
        scriptExecutor.addShutdownListener(listener1);

        // Add second listener (should replace first)
        TestShutdownListener listener2 = new TestShutdownListener();
        scriptExecutor.addShutdownListener(listener2);

        // Call shutdown
        scriptExecutor.shutdown();

    }

    /**
     * Adds a shutdown listener to be notified when the executor is shutting down.
     *
     * @param listener the shutdown listener to add
     */
    public void addShutdownListener(final ShutdownListener listener) {
        shutdownListener = listener;
    }

    /**
     * Interface for listening to shutdown events.
     */
    public interface ShutdownListener {
        /**

            sessionId = RandomStringUtils.randomAlphabetic(15);
        }
        resultBuf.append("Session Id: ").append(sessionId).append("\n");
        if (jobExecutor != null) {
            jobExecutor.addShutdownListener(() -> ComponentUtil.getProcessHelper().destroyProcess(sessionId));
        }

        final TimeoutTask timeoutTask = createTimeoutTask();
        try {
            executePython();

        final List<JobExecutor.ShutdownListener> shutdownListeners = new ArrayList<>();

        JobExecutor mockJobExecutor = new JobExecutor() {
            @Override
            public void addShutdownListener(ShutdownListener listener) {
                shutdownListeners.add(listener);
            }

            @Override
            public Object execute(String scriptType, String script) {

    private class MockJobExecutor extends JobExecutor {
        private boolean hasShutdownListener = false;

        @Override
        public void addShutdownListener(ShutdownListener listener) {
            hasShutdownListener = true;
            super.addShutdownListener(listener);
        }

        @Override
        public Object execute(String scriptType, String script) {
            return null;
        }

            sessionId = RandomStringUtils.randomAlphabetic(15);
        }
        resultBuf.append("Session Id: ").append(sessionId).append("\n");
        if (jobExecutor != null) {
            jobExecutor.addShutdownListener(() -> ComponentUtil.getProcessHelper().destroyProcess(sessionId));
        }

        final TimeoutTask timeoutTask = createTimeoutTask();
        try {
            executeSuggestCreator();

            sessionId = RandomStringUtils.randomAlphabetic(15);
        }
        resultBuf.append("Session Id: ").append(sessionId).append("\n");
        if (jobExecutor != null) {
            jobExecutor.addShutdownListener(() -> ComponentUtil.getProcessHelper().destroyProcess(sessionId));
        }

        final TimeoutTask timeoutTask = createTimeoutTask();
        try {
            executeThumbnailGenerator();

        }
    }

    private static class TestJobExecutor extends JobExecutor {
        boolean shutdownListenerAdded = false;

        @Override
        public void addShutdownListener(ShutdownListener listener) {
            shutdownListenerAdded = true;
            listener.onShutdown();
        }

        @Override
        public Object execute(String scriptType, String script) {

                resultBuf.append(' ').append(id);
            }
            resultBuf.append('\n');
        }

        if (jobExecutor != null) {
            jobExecutor.addShutdownListener(() -> ComponentUtil.getProcessHelper().destroyProcess(sessionId));
        }

        final TimeoutTask timeoutTask = createTimeoutTask();
        try {
            executeCrawler();