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/* * Copyright 2002-2018 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.config; import java.util.ArrayList; import java.util.Collections; import java.util.Date; import java.util.HashMap; import java.util.LinkedHashSet; import java.util.List; import java.util.Map; import java.util.Set; import java.util.concurrent.Executors; import java.util.concurrent.ScheduledExecutorService; import org.springframework.beans.factory.DisposableBean; import org.springframework.beans.factory.InitializingBean; import org.springframework.lang.Nullable; import org.springframework.scheduling.TaskScheduler; import org.springframework.scheduling.Trigger; import org.springframework.scheduling.concurrent.ConcurrentTaskScheduler; import org.springframework.scheduling.support.CronTrigger; import org.springframework.util.Assert; import org.springframework.util.CollectionUtils; /** * Helper bean for registering tasks with a {@link TaskScheduler}, typically using cron * expressions. * * <p>As of Spring 3.1, {@code ScheduledTaskRegistrar} has a more prominent user-facing * role when used in conjunction with the @{@link * org.springframework.scheduling.annotation.EnableAsync EnableAsync} annotation and its * {@link org.springframework.scheduling.annotation.SchedulingConfigurer * SchedulingConfigurer} callback interface. * * @author Juergen Hoeller * @author Chris Beams * @author Tobias Montagna-Hay * @since 3.0 * @see org.springframework.scheduling.annotation.EnableAsync * @see org.springframework.scheduling.annotation.SchedulingConfigurer */ public class ScheduledTaskRegistrar implements ScheduledTaskHolder, InitializingBean, DisposableBean { @Nullable private TaskScheduler taskScheduler; @Nullable private ScheduledExecutorService localExecutor; @Nullable private List<TriggerTask> triggerTasks; @Nullable private List<CronTask> cronTasks; @Nullable private List<IntervalTask> fixedRateTasks; @Nullable private List<IntervalTask> fixedDelayTasks; private final Map<Task, ScheduledTask> unresolvedTasks = new HashMap<>(16); private final Set<ScheduledTask> scheduledTasks = new LinkedHashSet<>(16); /** * Set the {@link TaskScheduler} to register scheduled tasks with. */ public void setTaskScheduler(TaskScheduler taskScheduler) { Assert.notNull(taskScheduler, "TaskScheduler must not be null"); this.taskScheduler = taskScheduler; } /** * Set the {@link TaskScheduler} to register scheduled tasks with, or a * {@link java.util.concurrent.ScheduledExecutorService} to be wrapped as a * {@code TaskScheduler}. */ public void setScheduler(@Nullable Object scheduler) { if (scheduler == null) { this.taskScheduler = null; } else if (scheduler instanceof TaskScheduler) { this.taskScheduler = (TaskScheduler) scheduler; } else if (scheduler instanceof ScheduledExecutorService) { this.taskScheduler = new ConcurrentTaskScheduler(((ScheduledExecutorService) scheduler)); } else { throw new IllegalArgumentException("Unsupported scheduler type: " + scheduler.getClass()); } } /** * Return the {@link TaskScheduler} instance for this registrar (may be {@code null}). */ @Nullable public TaskScheduler getScheduler() { return this.taskScheduler; } /** * Specify triggered tasks as a Map of Runnables (the tasks) and Trigger objects * (typically custom implementations of the {@link Trigger} interface). */ public void setTriggerTasks(Map<Runnable, Trigger> triggerTasks) { this.triggerTasks = new ArrayList<>(); triggerTasks.forEach((task, trigger) -> addTriggerTask(new TriggerTask(task, trigger))); } /** * Specify triggered tasks as a list of {@link TriggerTask} objects. Primarily used * by {@code <task:*>} namespace parsing. * @since 3.2 * @see ScheduledTasksBeanDefinitionParser */ public void setTriggerTasksList(List<TriggerTask> triggerTasks) { this.triggerTasks = triggerTasks; } /** * Get the trigger tasks as an unmodifiable list of {@link TriggerTask} objects. * @return the list of tasks (never {@code null}) * @since 4.2 */ public List<TriggerTask> getTriggerTaskList() { return (this.triggerTasks != null ? Collections.unmodifiableList(this.triggerTasks) : Collections.emptyList()); } /** * Specify triggered tasks as a Map of Runnables (the tasks) and cron expressions. * @see CronTrigger */ public void setCronTasks(Map<Runnable, String> cronTasks) { this.cronTasks = new ArrayList<>(); cronTasks.forEach(this::addCronTask); } /** * Specify triggered tasks as a list of {@link CronTask} objects. Primarily used by * {@code <task:*>} namespace parsing. * @since 3.2 * @see ScheduledTasksBeanDefinitionParser */ public void setCronTasksList(List<CronTask> cronTasks) { this.cronTasks = cronTasks; } /** * Get the cron tasks as an unmodifiable list of {@link CronTask} objects. * @return the list of tasks (never {@code null}) * @since 4.2 */ public List<CronTask> getCronTaskList() { return (this.cronTasks != null ? Collections.unmodifiableList(this.cronTasks) : Collections.emptyList()); } /** * Specify triggered tasks as a Map of Runnables (the tasks) and fixed-rate values. * @see TaskScheduler#scheduleAtFixedRate(Runnable, long) */ public void setFixedRateTasks(Map<Runnable, Long> fixedRateTasks) { this.fixedRateTasks = new ArrayList<>(); fixedRateTasks.forEach(this::addFixedRateTask); } /** * Specify fixed-rate tasks as a list of {@link IntervalTask} objects. Primarily used * by {@code <task:*>} namespace parsing. * @since 3.2 * @see ScheduledTasksBeanDefinitionParser */ public void setFixedRateTasksList(List<IntervalTask> fixedRateTasks) { this.fixedRateTasks = fixedRateTasks; } /** * Get the fixed-rate tasks as an unmodifiable list of {@link IntervalTask} objects. * @return the list of tasks (never {@code null}) * @since 4.2 */ public List<IntervalTask> getFixedRateTaskList() { return (this.fixedRateTasks != null ? Collections.unmodifiableList(this.fixedRateTasks) : Collections.emptyList()); } /** * Specify triggered tasks as a Map of Runnables (the tasks) and fixed-delay values. * @see TaskScheduler#scheduleWithFixedDelay(Runnable, long) */ public void setFixedDelayTasks(Map<Runnable, Long> fixedDelayTasks) { this.fixedDelayTasks = new ArrayList<>(); fixedDelayTasks.forEach(this::addFixedDelayTask); } /** * Specify fixed-delay tasks as a list of {@link IntervalTask} objects. Primarily used * by {@code <task:*>} namespace parsing. * @since 3.2 * @see ScheduledTasksBeanDefinitionParser */ public void setFixedDelayTasksList(List<IntervalTask> fixedDelayTasks) { this.fixedDelayTasks = fixedDelayTasks; } /** * Get the fixed-delay tasks as an unmodifiable list of {@link IntervalTask} objects. * @return the list of tasks (never {@code null}) * @since 4.2 */ public List<IntervalTask> getFixedDelayTaskList() { return (this.fixedDelayTasks != null ? Collections.unmodifiableList(this.fixedDelayTasks) : Collections.emptyList()); } /** * Add a Runnable task to be triggered per the given {@link Trigger}. * @see TaskScheduler#scheduleAtFixedRate(Runnable, long) */ public void addTriggerTask(Runnable task, Trigger trigger) { addTriggerTask(new TriggerTask(task, trigger)); } /** * Add a {@code TriggerTask}. * @since 3.2 * @see TaskScheduler#scheduleAtFixedRate(Runnable, long) */ public void addTriggerTask(TriggerTask task) { if (this.triggerTasks == null) { this.triggerTasks = new ArrayList<>(); } this.triggerTasks.add(task); } /** * Add a Runnable task to be triggered per the given cron expression. */ public void addCronTask(Runnable task, String expression) { addCronTask(new CronTask(task, expression)); } /** * Add a {@link CronTask}. * @since 3.2 */ public void addCronTask(CronTask task) { if (this.cronTasks == null) { this.cronTasks = new ArrayList<>(); } this.cronTasks.add(task); } /** * Add a {@code Runnable} task to be triggered at the given fixed-rate interval. * @see TaskScheduler#scheduleAtFixedRate(Runnable, long) */ public void addFixedRateTask(Runnable task, long interval) { addFixedRateTask(new IntervalTask(task, interval, 0)); } /** * Add a fixed-rate {@link IntervalTask}. * @since 3.2 * @see TaskScheduler#scheduleAtFixedRate(Runnable, long) */ public void addFixedRateTask(IntervalTask task) { if (this.fixedRateTasks == null) { this.fixedRateTasks = new ArrayList<>(); } this.fixedRateTasks.add(task); } /** * Add a Runnable task to be triggered with the given fixed delay. * @see TaskScheduler#scheduleWithFixedDelay(Runnable, long) */ public void addFixedDelayTask(Runnable task, long delay) { addFixedDelayTask(new IntervalTask(task, delay, 0)); } /** * Add a fixed-delay {@link IntervalTask}. * @since 3.2 * @see TaskScheduler#scheduleWithFixedDelay(Runnable, long) */ public void addFixedDelayTask(IntervalTask task) { if (this.fixedDelayTasks == null) { this.fixedDelayTasks = new ArrayList<>(); } this.fixedDelayTasks.add(task); } /** * Return whether this {@code ScheduledTaskRegistrar} has any tasks registered. * @since 3.2 */ public boolean hasTasks() { return (!CollectionUtils.isEmpty(this.triggerTasks) || !CollectionUtils.isEmpty(this.cronTasks) || !CollectionUtils.isEmpty(this.fixedRateTasks) || !CollectionUtils.isEmpty(this.fixedDelayTasks)); } /** * Calls {@link #scheduleTasks()} at bean construction time. */ @Override public void afterPropertiesSet() { scheduleTasks(); } /** * Schedule all registered tasks against the underlying * {@linkplain #setTaskScheduler(TaskScheduler) task scheduler}. */ @SuppressWarnings("deprecation") protected void scheduleTasks() { if (this.taskScheduler == null) { this.localExecutor = Executors.newSingleThreadScheduledExecutor(); this.taskScheduler = new ConcurrentTaskScheduler(this.localExecutor); } if (this.triggerTasks != null) { for (TriggerTask task : this.triggerTasks) { addScheduledTask(scheduleTriggerTask(task)); } } if (this.cronTasks != null) { for (CronTask task : this.cronTasks) { addScheduledTask(scheduleCronTask(task)); } } if (this.fixedRateTasks != null) { for (IntervalTask task : this.fixedRateTasks) { addScheduledTask(scheduleFixedRateTask(task)); } } if (this.fixedDelayTasks != null) { for (IntervalTask task : this.fixedDelayTasks) { addScheduledTask(scheduleFixedDelayTask(task)); } } } private void addScheduledTask(@Nullable ScheduledTask task) { if (task != null) { this.scheduledTasks.add(task); } } /** * Schedule the specified trigger task, either right away if possible * or on initialization of the scheduler. * @return a handle to the scheduled task, allowing to cancel it * @since 4.3 */ @Nullable public ScheduledTask scheduleTriggerTask(TriggerTask task) { ScheduledTask scheduledTask = this.unresolvedTasks.remove(task); boolean newTask = false; if (scheduledTask == null) { scheduledTask = new ScheduledTask(task); newTask = true; } if (this.taskScheduler != null) { scheduledTask.future = this.taskScheduler.schedule(task.getRunnable(), task.getTrigger()); } else { addTriggerTask(task); this.unresolvedTasks.put(task, scheduledTask); } return (newTask ? scheduledTask : null); } /** * Schedule the specified cron task, either right away if possible * or on initialization of the scheduler. * @return a handle to the scheduled task, allowing to cancel it * (or {@code null} if processing a previously registered task) * @since 4.3 */ @Nullable public ScheduledTask scheduleCronTask(CronTask task) { ScheduledTask scheduledTask = this.unresolvedTasks.remove(task); boolean newTask = false; if (scheduledTask == null) { scheduledTask = new ScheduledTask(task); newTask = true; } if (this.taskScheduler != null) { scheduledTask.future = this.taskScheduler.schedule(task.getRunnable(), task.getTrigger()); } else { addCronTask(task); this.unresolvedTasks.put(task, scheduledTask); } return (newTask ? scheduledTask : null); } /** * Schedule the specified fixed-rate task, either right away if possible * or on initialization of the scheduler. * @return a handle to the scheduled task, allowing to cancel it * (or {@code null} if processing a previously registered task) * @since 4.3 * @deprecated as of 5.0.2, in favor of {@link #scheduleFixedRateTask(FixedRateTask)} */ @Deprecated @Nullable public ScheduledTask scheduleFixedRateTask(IntervalTask task) { FixedRateTask taskToUse = (task instanceof FixedRateTask ? (FixedRateTask) task : new FixedRateTask(task.getRunnable(), task.getInterval(), task.getInitialDelay())); return scheduleFixedRateTask(taskToUse); } /** * Schedule the specified fixed-rate task, either right away if possible * or on initialization of the scheduler. * @return a handle to the scheduled task, allowing to cancel it * (or {@code null} if processing a previously registered task) * @since 5.0.2 */ @Nullable public ScheduledTask scheduleFixedRateTask(FixedRateTask task) { ScheduledTask scheduledTask = this.unresolvedTasks.remove(task); boolean newTask = false; if (scheduledTask == null) { scheduledTask = new ScheduledTask(task); newTask = true; } if (this.taskScheduler != null) { if (task.getInitialDelay() > 0) { Date startTime = new Date(System.currentTimeMillis() + task.getInitialDelay()); scheduledTask.future = this.taskScheduler.scheduleAtFixedRate(task.getRunnable(), startTime, task.getInterval()); } else { scheduledTask.future = this.taskScheduler.scheduleAtFixedRate(task.getRunnable(), task.getInterval()); } } else { addFixedRateTask(task); this.unresolvedTasks.put(task, scheduledTask); } return (newTask ? scheduledTask : null); } /** * Schedule the specified fixed-delay task, either right away if possible * or on initialization of the scheduler. * @return a handle to the scheduled task, allowing to cancel it * (or {@code null} if processing a previously registered task) * @since 4.3 * @deprecated as of 5.0.2, in favor of {@link #scheduleFixedDelayTask(FixedDelayTask)} */ @Deprecated @Nullable public ScheduledTask scheduleFixedDelayTask(IntervalTask task) { FixedDelayTask taskToUse = (task instanceof FixedDelayTask ? (FixedDelayTask) task : new FixedDelayTask(task.getRunnable(), task.getInterval(), task.getInitialDelay())); return scheduleFixedDelayTask(taskToUse); } /** * Schedule the specified fixed-delay task, either right away if possible * or on initialization of the scheduler. * @return a handle to the scheduled task, allowing to cancel it * (or {@code null} if processing a previously registered task) * @since 5.0.2 */ @Nullable public ScheduledTask scheduleFixedDelayTask(FixedDelayTask task) { ScheduledTask scheduledTask = this.unresolvedTasks.remove(task); boolean newTask = false; if (scheduledTask == null) { scheduledTask = new ScheduledTask(task); newTask = true; } if (this.taskScheduler != null) { if (task.getInitialDelay() > 0) { Date startTime = new Date(System.currentTimeMillis() + task.getInitialDelay()); scheduledTask.future = this.taskScheduler.scheduleWithFixedDelay(task.getRunnable(), startTime, task.getInterval()); } else { scheduledTask.future = this.taskScheduler.scheduleWithFixedDelay(task.getRunnable(), task.getInterval()); } } else { addFixedDelayTask(task); this.unresolvedTasks.put(task, scheduledTask); } return (newTask ? scheduledTask : null); } /** * Return all locally registered tasks that have been scheduled by this registrar. * @since 5.0.2 * @see #addTriggerTask * @see #addCronTask * @see #addFixedRateTask * @see #addFixedDelayTask */ @Override public Set<ScheduledTask> getScheduledTasks() { return Collections.unmodifiableSet(this.scheduledTasks); } @Override public void destroy() { for (ScheduledTask task : this.scheduledTasks) { task.cancel(); } if (this.localExecutor != null) { this.localExecutor.shutdownNow(); } } }