The JobDataMap can be used to hold any amount of (serializable) data objects which you wish to have made available to the job instance when it executes. JobDataMap is an implementation of the Java Map interface, and has some added convenience methods for storing and retrieving data of primitive types.

Here's some snippets of putting data into the JobDataMap while defining/building the JobDetail, prior to adding the job to the scheduler:

JobDetail jobDetail = JobBuilder.newJob(HelloJob.class)

                                .withIdentity("helloJob", Scheduler.DEFAULT_GROUP)

                                .usingJobData("msg", "hello JobDataMap.")

                                .build(); 

Here is an example of getting data from the JobDataMap during the job's execution:

public class HelloJob implements Job {

    public void execute(JobExecutionContext context) throws JobExecutionException {

        String msg = context.getJobDetail().getJobDataMap().getString("msg");

        System.out.println("msg: " + msg);

    }

}

If you add setter methods to your job class that correspond to the names of keys in the JobDataMap (such as a setMsg(String msg) method for the data in the example above), then Quartz's default JobFactory implementation will automatically call those setters when the job is instantiated, thus preventing the need to explicitly get the values out of the map within your execute method.

public class HelloJob implements Job {

    @Setter

    private String msg;

    public void execute(JobExecutionContext context) throws JobExecutionException {

        System.out.println("msg: " + msg);

    }

}