com.sun.sgs.impl.kernel.schedule
Class ImmediateRetryPolicy

java.lang.Object
  com.sun.sgs.impl.kernel.schedule.ImmediateRetryPolicy

All Implemented Interfaces:

SchedulerRetryPolicy

public class ImmediateRetryPolicy
extends Object
implements SchedulerRetryPolicy

A simple retry "in place" SchedulerRetryPolicy. This SchedulerRetryPolicy always causes a task that throws a retryable exception to retry immediately. This class supports the following configuration properties:

Property: "com.sun.sgs.impl.kernel.schedule.retry.warning.threshold"
Default: 25

If a task has been retried a multiple of times equal to the value of this property, then a WARNING message will be logged as feedback to the user. This value must be greater than or equal to 1.

Field Summary

(package private) static int	DEFAULT_RETRY_WARNING_THRESHOLD The default retry warning threshold
(package private) static String	RETRY_WARNING_THRESHOLD_PROPERTY The property used to define the retry count threshold to use before printing a WARNING message.

Constructor Summary

ImmediateRetryPolicy(Properties properties)
Constructs an ImmediateRetryPolicy.

Method Summary

SchedulerRetryAction

getRetryAction(ScheduledTask task) Determines if and how a task should be retried after a failure.

Methods inherited from class java.lang.Object

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

Field Detail

RETRY_WARNING_THRESHOLD_PROPERTY

static final String RETRY_WARNING_THRESHOLD_PROPERTY

The property used to define the retry count threshold to use before printing a WARNING message.

See Also:

Constant Field Values

DEFAULT_RETRY_WARNING_THRESHOLD

static final int DEFAULT_RETRY_WARNING_THRESHOLD

The default retry warning threshold

See Also:

Constant Field Values

Constructor Detail

ImmediateRetryPolicy

public ImmediateRetryPolicy(Properties properties)

Constructs an ImmediateRetryPolicy.

Parameters:

properties - the system properties available

Method Detail

getRetryAction

public SchedulerRetryAction getRetryAction(ScheduledTask task)

Determines if and how a task should be retried after a failure. This method should be called by a scheduler if a task aborts.

• A return value of SchedulerRetryAction.DROP means that the task should be dropped and not retried.
• A return value of SchedulerRetryAction.RETRY_LATER means that the task should be retried by the scheduler at some point in the future.
• A return value of SchedulerRetryAction.RETRY_NOW means that the task should be retried immediately.

This method may modify the given task in order to affect how the scheduler behaves when re-executing.

Note: The Throwable cause of the most recent failure of the given task should always be accessible via the ScheduledTask.getLastFailure() method. This Throwable may implement ExceptionRetryStatus. If it does, care should be taken to abide by the contract specified by the TaskManager with regard to Throwables that implement this interface.

Note: The proper way to drop a task with a custom policy is to return DROP with this method. Implementations should not use a call to cancel on the given task.

Specified by:

getRetryAction in interface SchedulerRetryPolicy

Parameters:

task - the task that has been aborted

Returns:

the SchedulerRetryAction that the scheduler should take with respect to retrying the given task