Now, some additional notes about a job's state data (aka JobDataMap): A Job instance can be defined as "stateful" or "non-stateful". Non-stateful jobs only have their JobDataMap stored at the time they are added to the scheduler. This means that any changes made to the contents of the job data map during execution of the job will be lost, and will not seen by the job the next time it executes. You have probably guessed, a stateful job is just the opposite - its JobDataMap is re-stored after every execution of the job. One side-effect of making a job stateful is that it cannot be executed concurrently. Or in other words: if a job is stateful, and a trigger attempts to 'fire' the job while it is already executing, the trigger will block (wait) until the previous execution completes.