com.atlassian.scheduler.core.util

Class CronExpressionQuantizer

java.lang.Object

com.atlassian.scheduler.core.util.CronExpressionQuantizer

public class CronExpressionQuantizer
extends Object

Utility class to prevent the use of cron expressions that run more frequently than once per minute. It is assumed that the cron expression has already been validated or that it is acceptable for the validation to return the "wrong" message when the expression is validated later on.

Without this, people could supply cron expressions that run every five seconds or something equally inappropriate.

Since:

v1.0

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	CronExpressionQuantizer.Randomize Controls whether or not randomization is performed when a cron expression is quantized.

Constructor Summary

Constructors

Constructor and Description
CronExpressionQuantizer()

Method Summary

Modifier and Type	Method and Description
static String	quantizeSecondsField(String cronExpression) Quantize the seconds field using CronExpressionQuantizer.Randomize.AS_NEEDED.
static String	quantizeSecondsField(String cronExpression, CronExpressionQuantizer.Randomize randomize) Quantize the seconds field, randomizing it as requested.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

CronExpressionQuantizer

public CronExpressionQuantizer()

Method Detail

quantizeSecondsField

public static String quantizeSecondsField(String cronExpression)

Quantize the seconds field using CronExpressionQuantizer.Randomize.AS_NEEDED.

Parameters:

cronExpression - the cron expression to (possibly) quantize.

Returns:

the cron expression with the seconds field forced to a random value between 0 and 59 (inclusive) if it is not already in that format

quantizeSecondsField

public static String quantizeSecondsField(@Nullable
                                          String cronExpression,
                                          @Nullable
                                          CronExpressionQuantizer.Randomize randomize)

Quantize the seconds field, randomizing it as requested.

Parameters:

cronExpression - the cron expression to (possibly) quantize.

randomize - controls the randomization of the seconds fields (null is assumed to mean CronExpressionQuantizer.Randomize.AS_NEEDED.

Returns:

the cron expression with the seconds field forced to a value between 0 and 59 (inclusive) if it is not already in that format or as instructed to by the randomize option.