org.springframework.scheduling.support.PeriodicTrigger Maven / Gradle / Ivy
/*
* Copyright 2002-2022 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.scheduling.support;
import java.time.Duration;
import java.time.Instant;
import java.time.temporal.ChronoUnit;
import java.util.Objects;
import java.util.concurrent.TimeUnit;
import org.springframework.lang.Nullable;
import org.springframework.scheduling.Trigger;
import org.springframework.scheduling.TriggerContext;
import org.springframework.util.Assert;
/**
* A trigger for periodic task execution. The period may be applied as either
* fixed-rate or fixed-delay, and an initial delay value may also be configured.
* The default initial delay is 0, and the default behavior is fixed-delay
* (i.e. the interval between successive executions is measured from each
* completion time). To measure the interval between the
* scheduled start time of each execution instead, set the
* 'fixedRate' property to {@code true}.
*
* Note that the TaskScheduler interface already defines methods for scheduling
* tasks at fixed-rate or with fixed-delay. Both also support an optional value
* for the initial delay. Those methods should be used directly whenever
* possible. The value of this Trigger implementation is that it can be used
* within components that rely on the Trigger abstraction. For example, it may
* be convenient to allow periodic triggers, cron-based triggers, and even
* custom Trigger implementations to be used interchangeably.
*
* @author Mark Fisher
* @since 3.0
*/
public class PeriodicTrigger implements Trigger {
private final Duration period;
@Nullable
private final ChronoUnit chronoUnit;
@Nullable
private volatile Duration initialDelay;
private volatile boolean fixedRate;
/**
* Create a trigger with the given period in milliseconds.
* @deprecated as of 6.0, in favor on {@link #PeriodicTrigger(Duration)}
*/
@Deprecated(since = "6.0")
public PeriodicTrigger(long period) {
this(period, null);
}
/**
* Create a trigger with the given period and time unit. The time unit will
* apply not only to the period but also to any 'initialDelay' value, if
* configured on this Trigger later via {@link #setInitialDelay(long)}.
* @deprecated as of 6.0, in favor on {@link #PeriodicTrigger(Duration)}
*/
@Deprecated(since = "6.0")
public PeriodicTrigger(long period, @Nullable TimeUnit timeUnit) {
this(toDuration(period, timeUnit), timeUnit);
}
private static Duration toDuration(long amount, @Nullable TimeUnit timeUnit) {
if (timeUnit != null) {
return Duration.of(amount, timeUnit.toChronoUnit());
}
else {
return Duration.ofMillis(amount);
}
}
/**
* Create a trigger with the given period as a duration.
* @since 6.0
*/
public PeriodicTrigger(Duration period) {
this(period, null);
}
private PeriodicTrigger(Duration period, @Nullable TimeUnit timeUnit) {
Assert.notNull(period, "Period must not be null");
Assert.isTrue(!period.isNegative(), "Period must not be negative");
this.period = period;
if (timeUnit != null) {
this.chronoUnit = timeUnit.toChronoUnit();
}
else {
this.chronoUnit = null;
}
}
/**
* Return this trigger's period.
* @since 5.0.2
* @deprecated as of 6.0, in favor on {@link #getPeriodDuration()}
*/
@Deprecated(since = "6.0")
public long getPeriod() {
if (this.chronoUnit != null) {
return this.period.get(this.chronoUnit);
}
else {
return this.period.toMillis();
}
}
/**
* Return this trigger's period.
* @since 6.0
*/
public Duration getPeriodDuration() {
return this.period;
}
/**
* Return this trigger's time unit (milliseconds by default).
* @since 5.0.2
* @deprecated as of 6.0, with no direct replacement
*/
@Deprecated(since = "6.0")
public TimeUnit getTimeUnit() {
if (this.chronoUnit != null) {
return TimeUnit.of(this.chronoUnit);
}
else {
return TimeUnit.MILLISECONDS;
}
}
/**
* Specify the delay for the initial execution. It will be evaluated in
* terms of this trigger's {@link TimeUnit}. If no time unit was explicitly
* provided upon instantiation, the default is milliseconds.
* @deprecated as of 6.0, in favor of {@link #setInitialDelay(Duration)}
*/
@Deprecated(since = "6.0")
public void setInitialDelay(long initialDelay) {
if (this.chronoUnit != null) {
this.initialDelay = Duration.of(initialDelay, this.chronoUnit);
}
else {
this.initialDelay = Duration.ofMillis(initialDelay);
}
}
/**
* Specify the delay for the initial execution.
* @since 6.0
*/
public void setInitialDelay(Duration initialDelay) {
this.initialDelay = initialDelay;
}
/**
* Return the initial delay, or 0 if none.
* @since 5.0.2
* @deprecated as of 6.0, in favor on {@link #getInitialDelayDuration()}
*/
@Deprecated(since = "6.0")
public long getInitialDelay() {
Duration initialDelay = this.initialDelay;
if (initialDelay != null) {
if (this.chronoUnit != null) {
return initialDelay.get(this.chronoUnit);
}
else {
return initialDelay.toMillis();
}
}
else {
return 0;
}
}
/**
* Return the initial delay, or {@code null} if none.
* @since 6.0
*/
@Nullable
public Duration getInitialDelayDuration() {
return this.initialDelay;
}
/**
* Specify whether the periodic interval should be measured between the
* scheduled start times rather than between actual completion times.
* The latter, "fixed delay" behavior, is the default.
*/
public void setFixedRate(boolean fixedRate) {
this.fixedRate = fixedRate;
}
/**
* Return whether this trigger uses fixed rate ({@code true}) or
* fixed delay ({@code false}) behavior.
* @since 5.0.2
*/
public boolean isFixedRate() {
return this.fixedRate;
}
/**
* Returns the time after which a task should run again.
*/
@Override
public Instant nextExecution(TriggerContext triggerContext) {
Instant lastExecution = triggerContext.lastScheduledExecution();
Instant lastCompletion = triggerContext.lastCompletion();
if (lastExecution == null || lastCompletion == null) {
Instant instant = triggerContext.getClock().instant();
Duration initialDelay = this.initialDelay;
if (initialDelay == null) {
return instant;
}
else {
return instant.plus(initialDelay);
}
}
if (this.fixedRate) {
return lastExecution.plus(this.period);
}
return lastCompletion.plus(this.period);
}
@Override
public boolean equals(@Nullable Object other) {
if (this == other) {
return true;
}
if (!(other instanceof PeriodicTrigger otherTrigger)) {
return false;
}
return (this.fixedRate == otherTrigger.fixedRate &&
this.period.equals(otherTrigger.period) &&
Objects.equals(this.initialDelay, otherTrigger.initialDelay));
}
@Override
public int hashCode() {
return this.period.hashCode();
}
}