public class QuartzCronPoller extends PollerImp
Implementation of Poller
which provides cron style scheduled polling based on the Quartz project.
A single Quartz Scheduler per Adapter (or Classloader) is used by all configured instances of QuartzCronPoller.
A file quartz.properties
is used to configure the Scheduler. This file is included in quartz.jar with default
settings which should be suitable for most of our purposes. In an Adapter deployment with more than 10 consumers using
QuartzCronPoller
you may wish to increase the size of the Scheduler
's thread pool. To do this place the
amended copy of the properties file in the Adapter Framework config directory.
For deployments with less 10 consumers using this Poller
, there is little or no benefit in increasing the size of the
thread pool; each AdaptrisPollingConsumer
instance is single threaded.
Although this class was created to allow 'every weekday at 10am' style scheduling, it can also be used to poll e.g. 'every 10 seconds'. Where a poll has not completed before the next scheduled poll is triggered, the subsequent poll will fail quietly, because it cannot obtain the associated lock.
The following is copied directly from the Quartz CronExpression javadocs.
Cron expressions are comprised of 6 required fields and one optional field separated by white space. The fields respectively are described as follows:Field Name | Allowed Values | Allowed Special Characters | ||
---|---|---|---|---|
Seconds |
0-59 |
, - * / |
||
Minutes |
0-59 |
, - * / |
||
Hours |
0-23 |
, - * / |
||
Day-of-month |
1-31 |
, - * ? / L W C |
||
Month |
1-12 or JAN-DEC |
, - * / |
||
Day-of-Week |
1-7 or SUN-SAT |
, - * ? / L # |
||
Year (Optional) |
empty, 1970-2099 |
, - * / |
The '?' character is allowed for the day-of-month and day-of-week fields. It is used to specify 'no specific value'. This is useful when you need to specify something in one of the two fileds, but not the other.
The '-' character is used to specify ranges For example "10-12" in the hour field means "the hours 10, 11 and 12".
The ',' character is used to specify additional values. For example "MON,WED,FRI" in the day-of-week field means "the days Monday, Wednesday, and Friday".
The '/' character is used to specify increments. For example "0/15" in the seconds field means "the seconds 0, 15, 30, and 45". And "5/15" in the seconds field means "the seconds 5, 20, 35, and 50". Specifying '*' before the '/' is equivalent to specifying 0 is the value to start with. Essentially, for each field in the expression, there is a set of numbers that can be turned on or off. For seconds and minutes, the numbers range from 0 to 59. For hours 0 to 23, for days of the month 0 to 31, and for months 1 to 12. The "/" character simply helps you turn on every "nth" value in the given set. Thus "7/6" in the month field only turns on month "7", it does NOT mean every 6th month, please note that subtlety.
The 'L' character is allowed for the day-of-month and day-of-week fields. This character is short-hand for "last", but it has different meaning in each of the two fields. For example, the value "L" in the day-of-month field means "the last day of the month" - day 31 for January, day 28 for February on non-leap years. If used in the day-of-week field by itself, it simply means "7" or "SAT". But if used in the day-of-week field after another value, it means "the last xxx day of the month" - for example "6L" means "the last friday of the month". When using the 'L' option, it is important not to specify lists, or ranges of values, as you'll get confusing results.
The 'W' character is allowed for the day-of-month field. This character is used to specify the weekday (Monday-Friday) nearest the given day. As an example, if you were to specify "15W" as the value for the day-of-month field, the meaning is: "the nearest weekday to the 15th of the month". So if the 15th is a Saturday, the trigger will fire on Friday the 14th. If the 15th is a Sunday, the trigger will fire on Monday the 16th. If the 15th is a Tuesday, then it will fire on Tuesday the 15th. However if you specify "1W" as the value for day-of-month, and the 1st is a Saturday, the trigger will fire on Monday the 3rd, as it will not 'jump' over the boundary of a month's days. The 'W' character can only be specified when the day-of-month is a single day, not a range or list of days.
The 'L' and 'W' characters can also be combined for the day-of-month expression to yield 'LW', which translates to "last weekday of the month".
The '#' character is allowed for the day-of-week field. This character is used to specify "the nth" day of the month. For example, the value of "6#3" in the day-of-week field means the third Friday of the month (day 6 = Friday and "#3" = the 3rd one in the month). Other examples: "2#1" = the first Monday of the month and "4#5" = the fifth Wednesday of the month. Note that if you specify "#5" and there is not 5 of the given day-of-week in the month, then no firing will occur that month.
The legal characters and the names of months and days of the week are not case sensitive.
Support for specifying both a day-of-week and a day-of-month value is not complete (you'll need to use the '?' character in on of these fields).
In the adapter configuration file this class is aliased as quartz-cron-poller which is the preferred alternative to the fully qualified classname when building your configuration.
Modifier and Type | Class and Description |
---|---|
static class |
QuartzCronPoller.MyProcessJob |
PollerImp.Callback
Constructor and Description |
---|
QuartzCronPoller()
Creates a new instance.
|
QuartzCronPoller(java.lang.String exp) |
QuartzCronPoller(java.lang.String exp,
java.lang.Boolean useCustomThreadPool) |
QuartzCronPoller(java.lang.String exp,
java.lang.String quartzId) |
Modifier and Type | Method and Description |
---|---|
void |
close()
Closes the component.
|
java.lang.String |
getCronExpression()
Return the cron expression to use.
|
protected org.quartz.JobKey |
getJobKey()
Creates a job key that encapsulates the job name and group name.
|
java.lang.String |
getName() |
java.lang.String |
getQuartzId() |
java.lang.String |
getSchedulerGroup() |
java.lang.Boolean |
getUseCustomThreadPool() |
void |
init()
Initialises the component.
|
void |
setCronExpression(java.lang.String s)
Sets the cron expression to use.
|
void |
setQuartzId(java.lang.String s)
Set the quartz id that will be registered.
|
void |
setSchedulerGroup(java.lang.String s)
Set the scheduler group.
|
void |
setUseCustomThreadPool(java.lang.Boolean b)
If set to true, then we use
NonBlockingQuartzThreadPool as the threadpool implementation for quartz. |
void |
start()
Starts the component.
|
void |
stop()
Stop the component
|
protected boolean |
useCustomThreadPool() |
attemptLock, processMessages, registerConsumer, releaseLock, retrieveConsumer, withPollerCallback
public QuartzCronPoller()
Creates a new instance. The default cron expression is 0 0,10,20,30,40,50 * * * ?
(every ten minutes every day,
from on the hour).
public QuartzCronPoller(java.lang.String exp)
public QuartzCronPoller(java.lang.String exp, java.lang.String quartzId)
public QuartzCronPoller(java.lang.String exp, java.lang.Boolean useCustomThreadPool)
public void init() throws CoreException
ComponentLifecycle
Component initialisation includes config verification, creation of connections etc.
CoreException
- wrapping any underlying Exception
sComponentLifecycle.init()
public void start() throws CoreException
ComponentLifecycle
Once a component is started it should be ready to process messages. In the case of
AdaptrisMessageConsumer
, calling start will begin message delivery.
CoreException
- wrapping any underlying Exception
sComponentLifecycle.start()
public void stop()
ComponentLifecycle
A stopped component is not expected to be ready to process messages. In the case of
AdaptrisMessageConsumer
, calling stop will pause message delivery. Throwing a
RuntimeException
may cause unintended consequences
public void close()
ComponentLifecycle
A closed component should release any connections it uses, etc. and clean up completely.
Throwing a RuntimeException
may cause unintended consequences
public java.lang.String getCronExpression()
Return the cron expression to use.
public void setCronExpression(java.lang.String s)
Sets the cron expression to use.
s
- the cron expression to usepublic java.lang.String getName()
public java.lang.String getQuartzId()
public void setQuartzId(java.lang.String s)
The quartz id acts as the name of the job, the name of the trigger, and the name of the triggerlistener. You should not need to configure this unless you are customising quartz.properties heavily; it is included for completeness.
s
- the quartz id; if null or empty, then one will be generated for you.public java.lang.String getSchedulerGroup()
public void setSchedulerGroup(java.lang.String s)
The 'group' feature may be useful for creating logical groupings or categorizations of Jobs. You should not need to configure this but is included for completeness.
s
- the scheduler group; if null or empty, then Scheduler.DEFAULT_GROUP
is used ('DEFAULT')protected org.quartz.JobKey getJobKey()
public java.lang.Boolean getUseCustomThreadPool()
public void setUseCustomThreadPool(java.lang.Boolean b)
NonBlockingQuartzThreadPool
as the threadpool implementation for quartz.
If set to false, then the default quartz.properties
are not modified when initialising the StdSchedulerFactory
;
however, mixing and matching thread pools between different instances is discouraged and may lead to undefined behaviour.
b
- false to disable our own thread pool, default true.protected boolean useCustomThreadPool()