ExecutorService executor = Executors.newFixedThreadPool(threadCount);

        for (int i = 0; i < threadCount; i++) {
            final int threadId = i;
            executor.submit(new Runnable() {
                @Override
                public void run() {
                    try {
                        startLatch.await();
                        for (int j = 0; j < operationsPerThread; j++) {

        final CountDownLatch endLatch = new CountDownLatch(threadCount);

        ExecutorService executor = Executors.newFixedThreadPool(threadCount);

        for (int i = 0; i < threadCount; i++) {
            executor.submit(new Runnable() {
                @Override
                public void run() {
                    try {
                        startLatch.await();
                        for (int j = 0; j < operationsPerThread; j++) {

      to that Work or Derivative Works thereof, that is intentionally
      submitted to Licensor for inclusion in the Work by the copyright owner
      or by an individual or Legal Entity authorized to submit on behalf of
      the copyright owner. For the purposes of this definition, "submitted"
      means any form of electronic, verbal, or written communication sent

      to that Work or Derivative Works thereof, that is intentionally
      submitted to Licensor for inclusion in the Work by the copyright owner
      or by an individual or Legal Entity authorized to submit on behalf of
      the copyright owner. For the purposes of this definition, "submitted"
      means any form of electronic, verbal, or written communication sent

        ExecutorService executor = Executors.newFixedThreadPool(threadCount);

        for (int i = 0; i < threadCount; i++) {
            final int threadId = i;
            executor.submit(new Runnable() {
                @Override
                public void run() {
                    try {
                        startLatch.await();
                        for (int j = 0; j < operationsPerThread; j++) {