Default time zone resolution from scheduler-wide Clock

Closes gh-31948

spring-context/src/main/java/org/springframework/scheduling/annotation/Scheduled.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -100,9 +100,9 @@ public @interface Scheduled {
 
 	/**
 	 * A time zone for which the cron expression will be resolved. By default, this
-	 * attribute is the empty String (i.e. the server's local time zone will be used).
+	 * attribute is the empty String (i.e. the scheduler's time zone will be used).
 	 * @return a zone id accepted by {@link java.util.TimeZone#getTimeZone(String)},
-	 * or an empty String to indicate the server's default time zone
+	 * or an empty String to indicate the scheduler's default time zone
 	 * @since 4.0
 	 * @see org.springframework.scheduling.support.CronTrigger#CronTrigger(String, java.util.TimeZone)
 	 * @see java.util.TimeZone

spring-context/src/main/java/org/springframework/scheduling/annotation/ScheduledAnnotationBeanPostProcessor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2023 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -27,7 +27,6 @@ import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
-import java.util.TimeZone;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ScheduledExecutorService;
 import java.util.concurrent.TimeUnit;
@@ -84,7 +83,7 @@ import org.springframework.util.StringValueResolver;
  * "fixedRate", "fixedDelay", or "cron" expression provided via the annotation.
  *
  * <p>This post-processor is automatically registered by Spring's
- * {@code <task:annotation-driven>} XML element, and also by the
+ * {@code <task:annotation-driven>} XML element and also by the
  * {@link EnableScheduling @EnableScheduling} annotation.
  *
  * <p>Autodetects any {@link SchedulingConfigurer} instances in the container,
@@ -434,14 +433,14 @@ public class ScheduledAnnotationBeanPostProcessor
 					Assert.isTrue(initialDelay == -1, "'initialDelay' not supported for cron triggers");
 					processedSchedule = true;
 					if (!Scheduled.CRON_DISABLED.equals(cron)) {
-						TimeZone timeZone;
+						CronTrigger trigger;
 						if (StringUtils.hasText(zone)) {
-							timeZone = StringUtils.parseTimeZoneString(zone);
+							trigger = new CronTrigger(cron, StringUtils.parseTimeZoneString(zone));
 						}
 						else {
-							timeZone = TimeZone.getDefault();
+							trigger = new CronTrigger(cron);
 						}
-						tasks.add(this.registrar.scheduleCronTask(new CronTask(runnable, new CronTrigger(cron, timeZone))));
+						tasks.add(this.registrar.scheduleCronTask(new CronTask(runnable, trigger)));
 					}
 				}
 			}

spring-context/src/main/java/org/springframework/scheduling/support/CronExpression.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2021 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -57,18 +57,12 @@ public final class CronExpression {
 	private final String expression;
 
 
-	private CronExpression(
-			CronField seconds,
-			CronField minutes,
-			CronField hours,
-			CronField daysOfMonth,
-			CronField months,
-			CronField daysOfWeek,
-			String expression) {
+	private CronExpression(CronField seconds, CronField minutes, CronField hours,
+			CronField daysOfMonth, CronField months, CronField daysOfWeek, String expression) {
 
-		// reverse order, to make big changes first
-		// to make sure we end up at 0 nanos, we add an extra field
-		this.fields = new CronField[]{daysOfWeek, months, daysOfMonth, hours, minutes, seconds, CronField.zeroNanos()};
+		// Reverse order, to make big changes first.
+		// To make sure we end up at 0 nanos, we add an extra field.
+		this.fields = new CronField[] {daysOfWeek, months, daysOfMonth, hours, minutes, seconds, CronField.zeroNanos()};
 		this.expression = expression;
 	}
 
@@ -121,11 +115,8 @@ public final class CronExpression {
 	 * {@code LW}), it means "the last weekday of the month".
 	 * </li>
 	 * <li>
-	 * In the "day of week" field, {@code L} stands for "the last day of the
-	 * week".
-	 * If prefixed by a number or three-letter name (i.e. {@code dL} or
-	 * {@code DDDL}), it means "the last day of week {@code d} (or {@code DDD})
-	 * in the month".
+	 * In the "day of week" field, {@code dL} or {@code DDDL} stands for
+	 * "the last day of week {@code d} (or {@code DDD}) in the month".
 	 * </li>
 	 * </ul>
 	 * </li>
@@ -177,7 +168,7 @@ public final class CronExpression {
 	 * the cron format
 	 */
 	public static CronExpression parse(String expression) {
-		Assert.hasLength(expression, "Expression string must not be empty");
+		Assert.hasLength(expression, "Expression must not be empty");
 
 		expression = resolveMacros(expression);
 
@@ -271,27 +262,18 @@ public final class CronExpression {
 
 
 	@Override
-	public int hashCode() {
-		return Arrays.hashCode(this.fields);
+	public boolean equals(@Nullable Object other) {
+		return (this == other || (other instanceof CronExpression &&
+				Arrays.equals(this.fields, ((CronExpression) other).fields)));
 	}
 
 	@Override
-	public boolean equals(Object o) {
-		if (this == o) {
-			return true;
-		}
-		if (o instanceof CronExpression) {
-			CronExpression other = (CronExpression) o;
-			return Arrays.equals(this.fields, other.fields);
-		}
-		else {
-			return false;
-		}
+	public int hashCode() {
+		return Arrays.hashCode(this.fields);
 	}
 
 	/**
 	 * Return the expression string used to create this {@code CronExpression}.
-	 * @return the expression string
 	 */
 	@Override
 	public String toString() {

spring-context/src/main/java/org/springframework/scheduling/support/CronTrigger.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2021 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -39,6 +39,7 @@ public class CronTrigger implements Trigger {
 
 	private final CronExpression expression;
 
+	@Nullable
 	private final ZoneId zoneId;
 
 
@@ -48,7 +49,8 @@ public class CronTrigger implements Trigger {
 	 * expression conventions
 	 */
 	public CronTrigger(String expression) {
-		this(expression, ZoneId.systemDefault());
+		this.expression = CronExpression.parse(expression);
+		this.zoneId = null;
 	}
 
 	/**
@@ -58,7 +60,9 @@ public class CronTrigger implements Trigger {
 	 * @param timeZone a time zone in which the trigger times will be generated
 	 */
 	public CronTrigger(String expression, TimeZone timeZone) {
-		this(expression, timeZone.toZoneId());
+		this.expression = CronExpression.parse(expression);
+		Assert.notNull(timeZone, "TimeZone must not be null");
+		this.zoneId = timeZone.toZoneId();
 	}
 
 	/**
@@ -70,10 +74,8 @@ public class CronTrigger implements Trigger {
 	 * @see CronExpression#parse(String)
 	 */
 	public CronTrigger(String expression, ZoneId zoneId) {
-		Assert.hasLength(expression, "Expression must not be empty");
-		Assert.notNull(zoneId, "ZoneId must not be null");
-
 		this.expression = CronExpression.parse(expression);
+		Assert.notNull(zoneId, "ZoneId must not be null");
 		this.zoneId = zoneId;
 	}
 
@@ -94,22 +96,23 @@ public class CronTrigger implements Trigger {
 	 */
 	@Override
 	public Date nextExecutionTime(TriggerContext triggerContext) {
-		Date date = triggerContext.lastCompletionTime();
-		if (date != null) {
+		Date timestamp = triggerContext.lastCompletionTime();
+		if (timestamp != null) {
 			Date scheduled = triggerContext.lastScheduledExecutionTime();
-			if (scheduled != null && date.before(scheduled)) {
+			if (scheduled != null && timestamp.before(scheduled)) {
 				// Previous task apparently executed too early...
 				// Let's simply use the last calculated execution time then,
 				// in order to prevent accidental re-fires in the same second.
-				date = scheduled;
+				timestamp = scheduled;
 			}
 		}
 		else {
-			date = new Date(triggerContext.getClock().millis());
+			timestamp = new Date(triggerContext.getClock().millis());
 		}
-		ZonedDateTime dateTime = ZonedDateTime.ofInstant(date.toInstant(), this.zoneId);
-		ZonedDateTime next = this.expression.next(dateTime);
-		return (next != null ? Date.from(next.toInstant()) : null);
+		ZoneId zone = (this.zoneId != null ? this.zoneId : triggerContext.getClock().getZone());
+		ZonedDateTime zonedTimestamp = ZonedDateTime.ofInstant(timestamp.toInstant(), zone);
+		ZonedDateTime nextTimestamp = this.expression.next(zonedTimestamp);
+		return (nextTimestamp != null ? Date.from(nextTimestamp.toInstant()) : null);
 	}
 
 

spring-context/src/test/java/org/springframework/scheduling/support/CronTriggerTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2021 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -848,6 +848,7 @@ class CronTriggerTests {
 		assertThat(nextExecutionTime).isEqualTo(this.calendar.getTime());
 	}
 
+
 	private static void roundup(Calendar calendar) {
 		calendar.add(Calendar.SECOND, 1);
 		calendar.set(Calendar.MILLISECOND, 0);
@@ -861,9 +862,7 @@ class CronTriggerTests {
 	}
 
 	private static TriggerContext getTriggerContext(Date lastCompletionTime) {
-		SimpleTriggerContext context = new SimpleTriggerContext();
-		context.update(null, null, lastCompletionTime);
-		return context;
+		return new SimpleTriggerContext(null, null, lastCompletionTime);
 	}