code: @Override
      public JobDetail retrieveJob(final JobKey jobKey) throws JobPersistenceException {
          return doWithLock(new LockCallback<JobDetail>() {
              @Override
              public JobDetail doWithLock(JedisCommands jedis) throws JobPersistenceException {
                  try {
                      return storage.retrieveJob(jobKey, jedis);
                  } catch (ClassNotFoundException e) {
                      throw new JobPersistenceException("Error retrieving job: " + e.getMessage(), e);
                  }
              }
          }, "Could not retrieve job.");
      }
docs: Retrieve the <code>{@link org.quartz.JobDetail}</code> for the given
  <code>{@link org.quartz.Job}</code>.
  
  @param jobKey the {@link org.quartz.JobKey} describing the desired job
  @return The desired <code>Job</code>, or null if there is no match.