sufficient description, if applicable unit tests are added, if it is a
  reasonable contribution (meaning it is not a single liner cosmetic PR).

**2. Valid?**

-   If the PR passes all the quality checks then we go ahead and assign a
    reviewer.
-   If the PR didn't meet the validation criteria, we request for additional
    changes to be made to PR to pass quality checks and send it back or on a
    rare occasion we may reject it.

    List<E> head = list.subList(0, size - 1);
    List<E> tail = list.subList(1, size);
    assertEquals(list.get(0), copy.get(0));
    assertEquals(list.get(size - 1), copy.get(size - 1));
    assertEquals(list.get(1), tail.get(0));
    assertEquals(list.get(size - 1), tail.get(size - 2));
    assertEquals(list.get(0), head.get(0));
    assertEquals(list.get(size - 2), head.get(size - 2));

                } catch (Exception e) {
                    logger.error("Thread {} failed", index, e);
                    results[index] = false;
                }
            });
            threads[i].start();
        }

        // Wait for all threads to complete
        for (Thread thread : threads) {
            thread.join();
        }

        // Then

 * currently supporting Kryo and JavaBin serialization formats. The serializer
 * type is determined by the crawler data serializer configuration.
 * </p>
 * <p>
 * The class is thread-safe and uses ThreadLocal to maintain Kryo instances
 * per thread to avoid synchronization overhead.
 * </p>
 *
 */
public class DataSerializer {

    /** Logger for this class. */

  }

  private void streamPrimesToSinkAsynchronously(final BufferedSink sink) {
    Thread thread = new Thread("writer") {
      @Override public void run() {
        try {
          sink.writeUtf8("Numbers\n");
          sink.writeUtf8("-------\n");
          for (int i = 2; i <= 997; i++) {
            System.out.println(i);
            Thread.sleep(10);
            sink.writeUtf8(String.format(" * %s = %s\n", i, factor(i)));
          }

        assertEquals(
                "{\"@timestamp\":\"2022-01-01T00:00:00.000Z\",\"log.level\":\"INFO\",\"ecs.version\":\"1.2.0\",\"service.name\":\"fess\",\"event.dataset\":\"app\",\"process.thread.name\":\"main\",\"log.logger\":\"org.codelibs.fess.helper.ActivityHelperTest$1\",\"labels.action\":\"LOGIN\",\"labels.user\":\"-\",\"labels.permissions\":\"-\"}",
                localLogMsg.get());

    }

    /**
     * Creates a new CurlRequest with the HTTP HEAD method for the specified URL.
     *
     * @param url the URL to which the HEAD request is to be made
     * @return a CurlRequest object configured with the HEAD method and the specified URL
     */
    public static CurlRequest head(final String url) {
        return new CurlRequest(Method.HEAD, url);
    }

    /**

        method.setAccessible(true);

        // Test with null thread
        try {
            method.invoke(crawler, (Thread) null);
        } catch (Exception e) {
            fail("Should not throw exception with null thread");
        }

        // Test with normal thread
        Thread testThread = new Thread(() -> {
            try {

    void testConcurrentLogging() throws InterruptedException {
        int threadCount = 10;
        int eventsPerThread = 100;
        Thread[] threads = new Thread[threadCount];

        for (int i = 0; i < threadCount; i++) {
            final int threadId = i;
            threads[i] = new Thread(() -> {
                for (int j = 0; j < eventsPerThread; j++) {

    }

    public void test_synchronizedFillInStackTrace() {
        // Test thread safety of fillInStackTrace method
        UserRoleLoginException exception = new UserRoleLoginException(RootAction.class);

        // Create multiple threads to test synchronized method
        Thread thread1 = new Thread(() -> {
            Throwable result = exception.fillInStackTrace();
            assertNull(result);