Package com.exedio.cope.util

Class ProxyJobContext

java.lang.Object

com.exedio.cope.util.ProxyJobContext

All Implemented Interfaces:

JobContext

public class ProxyJobContext
extends Object
implements JobContext

An proxy implementation of JobContext. All methods implementing JobContext do forward to another JobContext. You may want to subclass this class instead of implementing JobContext directly to make your subclass cope with new methods in JobContext.

Constructor Summary

Constructors

Constructor	Description
ProxyJobContext(JobContext target)

Method Summary

Modifier and Type	Method	Description
void	incrementProgress()	Indicates, that the job has proceeded.
void	incrementProgress(int delta)	Indicates, that the job has proceeded.
protected static Duration	max(Duration a, Duration b)
Duration	requestsDeferral()	When overriding this method make sure you don't ignore the request of the target.
void	setCompleteness(double completeness)	Indicates the current completeness of the job.
void	setMessage(String message)	Indicates a message describing the current status of the job.
void	sleepAndStopIfRequested(Duration duration)	Sleeps for the specified duration.
void	stopIfRequested()	Checks, whether the job has been requested to stop.
boolean	supportsCompleteness()	Returns whether this context can process information transferred by JobContext.setCompleteness(double).
boolean	supportsMessage()	Returns whether this context can process information transferred by JobContext.setMessage(String).
boolean	supportsProgress()	Returns whether this context can process information transferred by JobContext.incrementProgress() and JobContext.incrementProgress(int).

Methods inherited from class java.lang.Object

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

Constructor Detail

ProxyJobContext

public ProxyJobContext(JobContext target)

Method Detail

stopIfRequested

public void stopIfRequested()
                     throws JobStop

Description copied from interface: JobContext

Checks, whether the job has been requested to stop. The job should call this method in reasonably short intervals. If throws a JobStop, the job should stop gracefully as soon as possible, but all resources held should be released.

The job may call JobContext.deferOrStopIfRequested(JobContext) instead.

Specified by:

stopIfRequested in interface JobContext

Throws:

JobStop

requestsDeferral

public Duration requestsDeferral()

When overriding this method make sure you don't ignore the request of the target. You may want to use max(Duration, Duration) for merging requests.

Specified by:

requestsDeferral in interface JobContext

max

protected static final Duration max(Duration a,
                                    Duration b)

sleepAndStopIfRequested

public void sleepAndStopIfRequested(Duration duration)
                             throws JobStop

Description copied from interface: JobContext

Sleeps for the specified duration. In contrast to JobContext.deferOrStopIfRequested(JobContext) this method actually waits for the specified amount of time. In contrast to Thread.sleep it aborts prematurely by throwing a JobStop, if the the job has been requested to stop or becomes requested to stop while sleeping.

In general the job should not call this method directly, but only JobContext.sleepAndStopIfRequested(JobContext, Duration). Override this method for affecting (potentially long) sleeps. For instance the job might temporarily release resources.

Calling this method with duration zero or negative is equivalent to a call to JobContext.stopIfRequested().

The default implementation polls JobContext.stopIfRequested() every 100 milliseconds. Implementers are encouraged to provide a more efficient implementation. The default implementation fails for durations too large for Duration.toNanos(), which is approximately 292 years.

Specified by:

sleepAndStopIfRequested in interface JobContext

Throws:

JobStop

supportsMessage

public boolean supportsMessage()

Description copied from interface: JobContext

Returns whether this context can process information transferred by JobContext.setMessage(String).

Specified by:

supportsMessage in interface JobContext

setMessage

public void setMessage(String message)

Description copied from interface: JobContext

Indicates a message describing the current status of the job. Should be called only, if JobContext.supportsMessage() returns true. Otherwise calls are ignored.

Specified by:

setMessage in interface JobContext

supportsProgress

public boolean supportsProgress()

Description copied from interface: JobContext

Returns whether this context can process information transferred by JobContext.incrementProgress() and JobContext.incrementProgress(int).

Specified by:

supportsProgress in interface JobContext

incrementProgress

public void incrementProgress()

Description copied from interface: JobContext

Indicates, that the job has proceeded. There is no information available, when the job will return. Calling this method is equivalent to calling incrementProgress(1). Should be called only, if JobContext.supportsProgress() returns true. Otherwise calls are ignored.

Specified by:

incrementProgress in interface JobContext

incrementProgress

public void incrementProgress(int delta)

Description copied from interface: JobContext

Indicates, that the job has proceeded. There is no information available, when the job will return. Calling this method is equivalent to calling JobContext.incrementProgress() for the number of delta times. Parameter delta should be greater or equal 0. Values out of range are accepted as well, thus no exception is thrown in that case. Calling this method with delta of 0 is equivalent to not calling this method at all. Should be called only, if JobContext.supportsProgress() returns true. Otherwise calls are ignored.

Specified by:

incrementProgress in interface JobContext

supportsCompleteness

public boolean supportsCompleteness()

Description copied from interface: JobContext

Returns whether this context can process information transferred by JobContext.setCompleteness(double).

Specified by:

supportsCompleteness in interface JobContext

setCompleteness

public void setCompleteness(double completeness)

Description copied from interface: JobContext

Indicates the current completeness of the job. Parameter completeness should be between 0 and 1. Values out of range are accepted as well, thus no exception is thrown in that case. Should be called only, if JobContext.supportsCompleteness() returns true. Otherwise calls are ignored.

Specified by:

setCompleteness in interface JobContext