Advanced Topics - eXist: A NoSQL Database and Application Development Platform - page 437

Table 16-1. Scheduled job arguments

Argument Description Mandatory/optional

The type of the job to schedule. Either system for system task jobs or
user for user jobs.

Mandatory.

type

Used for specifying the fully qualified class name of your Java class that
implements either org.exist.scheduler.UserJavaJob or
org.exist.storage.SystemTask . a

Mandatory if job is
implemented in Java.

class

Used for specifying the database path to an XQuery if you have
implemented your scheduled job in XQuery. The syntax uses the simple
database path (e.g., /db/my-collection/my-job.xq ).

Mandatory if job is
implemented in XQuery.

xquery

When scheduling an XQuery job, you can provide a friendly name for the
scheduled job, but it must be unique across all scheduled jobs. Java jobs
implement their own name function.

Optional if XQuery job, and
otherwise ignored. The
default is the name of the
XQuery file.

name

When you're executing an XQuery job, if the job causes some sort of
exception it can be unscheduled so that it does not run again in the
future. Must be either yes or no .

Optional if XQuery job, and
otherwise ignored. The
default is yes .

unschedule-
on-exception

A description of when the scheduled job is run, using a cron-like syntax.
For the exact syntax, see http://www.quartz-scheduler.org/documenta
tion/quartz-1.x/tutorials/crontrigger .

Mandatory, or use
period instead.

cron-trigger

A period in milliseconds defining the frequency after any delay with
which the job is run.

Mandatory, or use cron-
trigger instead.

period

A startup delay in milliseconds after which the scheduled job is first run.
If unspecified, the job will be executed immediately after eXist has
initialized.

Optional; use with
period .

delay

The number of times to repeat execution of the job. If unspecified, the
job will be executed periodically indefinitely.

Optional; use with
period .

repeat

a Your Java class must be available on eXist's classpath, which you typically accom‐
plish by placing your JAR and any JAR dependencies into $EXIST_HOME/lib/user .

You may view the currently scheduled and executing jobs either by using the Schedu‐
ler dashboard application ( Figure 16-4 ) or by executing the scheduler:get-
scheduled-jobs XQuery extension function.