Package uk.ac.ebi.utils.runcontrol

Class ChainExecutor

java.lang.Object

uk.ac.ebi.utils.runcontrol.ChainExecutor

All Implemented Interfaces:

Executor

public class ChainExecutor
extends Object
implements Executor

An Executor that is able to chain/stack two other executors.

Author:

brandizi

Date:

6 Oct 2015

Constructor Summary

Constructors

Constructor	Description
ChainExecutor(Executor internalExecutor)	This reduces to running one executor only, so it's conceptually equivalent to use the internalExecutor straight, but it's a base to use andThen(Executor).
ChainExecutor(Executor externalExecutor, Executor internalExecutor)

Method Summary

Modifier and Type	Method	Description
ChainExecutor	andThen(Executor nextExecutor)	It's the reverse of wrap(Executor).
void	execute(Runnable action)	The external executor calls the run() method of the internal executor, passing the action to it.
ChainExecutor	wrap(Executor externalExecutor)	This allows you to indent multiple executors, without having to write big nested expressions.

Methods inherited from class java.lang.Object

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

Constructor Details

ChainExecutor

public ChainExecutor(Executor externalExecutor,
 Executor internalExecutor)

See Also:

• execute(Runnable)

ChainExecutor

public ChainExecutor(Executor internalExecutor)

This reduces to running one executor only, so it's conceptually equivalent to use the internalExecutor straight, but it's a base to use andThen(Executor).

Method Details

execute

public void execute(Runnable action)

The external executor calls the run() method of the internal executor, passing the action to it. The result is that the two executors wrap their job around the action in a nested way.

Specified by:

execute in interface Executor

wrap

public ChainExecutor wrap(Executor externalExecutor)

This allows you to indent multiple executors, without having to write big nested expressions. This is equivalent to creating a new executor using ChainExecutor(Executor, Executor) with the current instance as internal executor. So, it wraps the current executor with a new one.

This also implies that a composition like ex3(ex2(ex1)) here must be created via wrap( ex1 ).wrap ( ex2 ).wrap ( ex3 ).

andThen

public ChainExecutor andThen(Executor nextExecutor)

It's the reverse of wrap(Executor). Returns an executor that passes its runnable to this executor, which then invokes nextExecutor. This can be used to chain things inside-out: new ChainExecutor ( multiAttemptsExec ).andThen ( rateLimitedExec ) TODO: never tested!