HBASE-15791 Improve javadoc around ScheduledChore
Project: http://git-wip-us.apache.org/repos/asf/hbase/repo Commit: http://git-wip-us.apache.org/repos/asf/hbase/commit/541d1da5 Tree: http://git-wip-us.apache.org/repos/asf/hbase/tree/541d1da5 Diff: http://git-wip-us.apache.org/repos/asf/hbase/diff/541d1da5 Branch: refs/heads/hbase-12439 Commit: 541d1da5fee9e52f3d6dc86f754dbdec9dab1919 Parents: 05378cb Author: Jonathan M Hsieh <jmhs...@apache.org> Authored: Sat May 7 15:33:20 2016 -0700 Committer: Jonathan M Hsieh <jmhs...@apache.org> Committed: Mon May 9 08:41:28 2016 -0700 ---------------------------------------------------------------------- .../org/apache/hadoop/hbase/ScheduledChore.java | 37 +++++++++++++------- 1 file changed, 25 insertions(+), 12 deletions(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/hbase/blob/541d1da5/hbase-common/src/main/java/org/apache/hadoop/hbase/ScheduledChore.java ---------------------------------------------------------------------- diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/ScheduledChore.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/ScheduledChore.java index 2c54b9f..5c5bcd8 100644 --- a/hbase-common/src/main/java/org/apache/hadoop/hbase/ScheduledChore.java +++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/ScheduledChore.java @@ -55,9 +55,9 @@ public abstract class ScheduledChore implements Runnable { /** * Scheduling parameters. Used by ChoreService when scheduling the chore to run periodically */ - private final int period; + private final int period; // in TimeUnit units private final TimeUnit timeUnit; - private final long initialDelay; + private final long initialDelay; // in TimeUnit units /** * Interface to the ChoreService that this ScheduledChore is scheduled with. null if the chore is @@ -68,8 +68,8 @@ public abstract class ScheduledChore implements Runnable { /** * Variables that encapsulate the meaningful state information */ - private long timeOfLastRun = -1; - private long timeOfThisRun = -1; + private long timeOfLastRun = -1; // system time millis + private long timeOfThisRun = -1; // system time millis private boolean initialChoreComplete = false; /** @@ -127,7 +127,7 @@ public abstract class ScheduledChore implements Runnable { /** * @param name Name assigned to Chore. Useful for identification amongst chores of the same type * @param stopper When {@link Stoppable#isStopped()} is true, this chore will cancel and cleanup - * @param period Period with which this Chore repeats execution when scheduled. + * @param period Period in millis with which this Chore repeats execution when scheduled. */ public ScheduledChore(final String name, Stoppable stopper, final int period) { this(name, stopper, period, DEFAULT_INITIAL_DELAY); @@ -136,7 +136,7 @@ public abstract class ScheduledChore implements Runnable { /** * @param name Name assigned to Chore. Useful for identification amongst chores of the same type * @param stopper When {@link Stoppable#isStopped()} is true, this chore will cancel and cleanup - * @param period Period with which this Chore repeats execution when scheduled. + * @param period Period in millis with which this Chore repeats execution when scheduled. * @param initialDelay Delay before this Chore begins to execute once it has been scheduled. A * value of 0 means the chore will begin to execute immediately. Negative delays are * invalid and will be corrected to a value of 0. @@ -149,10 +149,10 @@ public abstract class ScheduledChore implements Runnable { /** * @param name Name assigned to Chore. Useful for identification amongst chores of the same type * @param stopper When {@link Stoppable#isStopped()} is true, this chore will cancel and cleanup - * @param period Period with which this Chore repeats execution when scheduled. - * @param initialDelay Delay before this Chore begins to execute once it has been scheduled. A - * value of 0 means the chore will begin to execute immediately. Negative delays are - * invalid and will be corrected to a value of 0. + * @param period Period in Timeunit unit with which this Chore repeats execution when scheduled. + * @param initialDelay Delay in Timeunit unit before this Chore begins to execute once it has been + * scheduled. A value of 0 means the chore will begin to execute immediately. Negative + * delays are invalid and will be corrected to a value of 0. * @param unit The unit that is used to measure period and initialDelay */ public ScheduledChore(final String name, Stoppable stopper, final int period, @@ -213,8 +213,8 @@ public abstract class ScheduledChore implements Runnable { } /** - * @return How long has it been since this chore last run. Useful for checking if the chore has - * missed its scheduled start time by too large of a margin + * @return How long in millis has it been since this chore last run. Useful for checking if the + * chore has missed its scheduled start time by too large of a margin */ synchronized long getTimeBetweenRuns() { return timeOfThisRun - timeOfLastRun; @@ -228,11 +228,18 @@ public abstract class ScheduledChore implements Runnable { && getTimeBetweenRuns() > getMaximumAllowedTimeBetweenRuns(); } + /** + * @return max allowed time in millis between runs. + */ private double getMaximumAllowedTimeBetweenRuns() { // Threshold used to determine if the Chore's current run started too late return 1.5 * timeUnit.toMillis(period); } + /** + * @param time in system millis + * @return true if time is earlier or equal to current milli time + */ private synchronized boolean isValidTime(final long time) { return time > 0 && time <= System.currentTimeMillis(); } @@ -276,10 +283,16 @@ public abstract class ScheduledChore implements Runnable { return stopper; } + /** + * @return period to execute chore in getTimeUnit() units + */ public int getPeriod() { return period; } + /** + * @return initial delay before executing chore in getTimeUnit() units + */ public long getInitialDelay() { return initialDelay; }
