EmbeddedCache cm = ...;
ClusteredLockManager cclm = EmbeddedClusteredLockManagerFactory.from(cm);

lock.tryLock()
  .thenCompose(result -> {
     if (result) {
      try {
          // manipulate protected state
          } finally {
             return lock.unlock();
          }
     } else {
        // Do something else
     }
  });
}