org.gcube.common.core.utils.handlers

Class GCUBEParallelHandler<HANDLED>

java.lang.Object

org.gcube.common.core.utils.handlers.GCUBEHandler<HANDLED>

org.gcube.common.core.utils.handlers.GCUBEComplexHandler<HANDLED>

org.gcube.common.core.utils.handlers.GCUBEParallelHandler<HANDLED>

Type Parameters:

HANDLED - the type of the handled object of the component handlers.

All Implemented Interfaces:

GCUBEIHandler<HANDLED>, Lifetime<HANDLED>

public class GCUBEParallelHandler<HANDLED>
extends GCUBEComplexHandler<HANDLED>
implements Lifetime<HANDLED>

An extension of GCUBEComplexHandler which parallelises the execution of the component handlers. A GCUBEParallelHandler propagates its state to all the component handlers (non-destructively). Failures are handled in accordance with either one of the two modes enumerated by GCUBEParallelHandler.Mode.

Author:

Fabio Simeoni (University of Strathclyde)

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	GCUBEParallelHandler.Mode Enumeration of the two failure handling modes of a GCUBEParallelHandler.
protected class	GCUBEParallelHandler.SlaveThread An extension of Thread which executes a component handler and records its potential errors.
protected class	GCUBEParallelHandler.SweeperThread An extension of Thread which waits for all component handlers to terminate before invoking GCUBEComplexHandler.undo().

Field Summary

Fields

Modifier and Type	Field and Description
protected Map<GCUBEIHandler<? extends HANDLED>,Exception>	failedHandlers Component handlers which have failed during the execution of the handler.
protected List<GCUBEParallelHandler.SlaveThread>	failedSlaves Per-component handler threads which have failed during the execution of the handler.
protected GCUBEParallelHandler.Mode	mode Failure mode for the execution of the handler.
protected List<GCUBEParallelHandler.SlaveThread>	runningSlaves Per-component handler threads spawned by the handler.

Fields inherited from class org.gcube.common.core.utils.handlers.GCUBEHandler

handled, logger, producer

Constructor Summary

Constructors

Constructor and Description
GCUBEParallelHandler(GCUBEIHandler<? extends HANDLED>... components) Creates an instance with a list of component handlers.
GCUBEParallelHandler(GCUBEParallelHandler.Mode mode) Creates an handler with a given failure handling mode.

Method Summary

Methods

Modifier and Type	Method and Description
Map<GCUBEIHandler<? extends HANDLED>,Exception>	getFailedHandlers() Returns the component handlers which have failed during execution of the handler, along with the corresponding failures.
GCUBEParallelHandler.Mode	getMode() Returns the failure handling mode of the handler.
void	run() Executes the task implemented by the handler.
void	setMode(GCUBEParallelHandler.Mode mode) Sets the failure handling mode of the handler.

Methods inherited from class org.gcube.common.core.utils.handlers.GCUBEComplexHandler

addHandlers, getHandlers, removeHandler, setLogger, undo

Methods inherited from class org.gcube.common.core.utils.handlers.GCUBEHandler

clearBlackboard, getBlackboard, getHandled, getId, getLogger, getName, getScopeManager, getSecurityManager, getState, notify, setBlackboard, setHandled, setName, setScopeManager, setSecurityManager, setState, subscribe, unsubscribe

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.gcube.common.core.utils.handlers.lifetime.Lifetime

getState

Methods inherited from interface org.gcube.common.core.utils.handlers.GCUBEIHandler

clearBlackboard, getBlackboard, getHandled, getId, getLogger, getName, getScopeManager, getSecurityManager, setBlackboard, setHandled, setLogger, setName, setScopeManager, setSecurityManager, subscribe, undo, unsubscribe

Field Detail

mode

protected GCUBEParallelHandler.Mode mode

Failure mode for the execution of the handler.

failedSlaves

protected List<GCUBEParallelHandler.SlaveThread> failedSlaves

Per-component handler threads which have failed during the execution of the handler.

runningSlaves

protected List<GCUBEParallelHandler.SlaveThread> runningSlaves

Per-component handler threads spawned by the handler.

failedHandlers

protected Map<GCUBEIHandler<? extends HANDLED>,Exception> failedHandlers

Component handlers which have failed during the execution of the handler.

Constructor Detail

GCUBEParallelHandler

public GCUBEParallelHandler(GCUBEIHandler<? extends HANDLED>... components)

Creates an instance with a list of component handlers.

Parameters:

components - the component handlers.

GCUBEParallelHandler

public GCUBEParallelHandler(GCUBEParallelHandler.Mode mode)

Creates an handler with a given failure handling mode.

Parameters:

mode - the failure handling mode.

Method Detail

getMode

public GCUBEParallelHandler.Mode getMode()

Returns the failure handling mode of the handler.

Returns:

the mode.

setMode

public void setMode(GCUBEParallelHandler.Mode mode)

Sets the failure handling mode of the handler.

Parameters:

mode - the mode.

getFailedHandlers

public Map<GCUBEIHandler<? extends HANDLED>,Exception> getFailedHandlers()

Returns the component handlers which have failed during execution of the handler, along with the corresponding failures.

Returns:

a list of (handler,exception) pairs.

run

public void run()
         throws Exception

Executes the task implemented by the handler.

Specified by:

run in interface GCUBEIHandler<HANDLED>

Specified by:

run in class GCUBEHandler<HANDLED>

Throws:

Exception - if the execution of the task does not complete normally.