package de.lmu.ifi.dbs.elki.parallel;
/*
This file is part of ELKI:
Environment for Developing KDD-Applications Supported by Index-Structures
Copyright (C) 2014
Ludwig-Maximilians-Universität München
Lehr- und Forschungseinheit für Datenbanksysteme
ELKI Development Team
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License
along with this program. If not, see .
*/
import java.util.HashMap;
import de.lmu.ifi.dbs.elki.database.ids.DBIDIter;
import de.lmu.ifi.dbs.elki.database.ids.DBIDs;
import de.lmu.ifi.dbs.elki.parallel.processor.Processor;
import de.lmu.ifi.dbs.elki.parallel.variables.SharedVariable;
import de.lmu.ifi.dbs.elki.parallel.variables.SharedVariable.Instance;
/**
* Class to process the whole data set in a single thread.
*
* Currently not used.
*
* @author Erich Schubert
*
* @apiviz.has SingleThreadedRunner
*/
public class SingleThreadedExecutor {
/**
* Run a task on a single thread.
*
* @param ids IDs to process
* @param procs Processors to run
*/
public static final void run(DBIDs ids, Processor... procs) {
new SingleThreadedRunner(ids, procs).run();
}
/**
* Run for an array part, without step size.
*
* @author Erich Schubert
*/
protected static class SingleThreadedRunner implements Executor {
/**
* Array IDs to process
*/
private DBIDs ids;
/**
* The process masters that own the instances.
*/
private Processor[] procs;
/**
* Variables map.
*/
private HashMap, SharedVariable.Instance>> variables = new HashMap<>();
/**
* Constructor.
*
* @param ids IDs to process
* @param procs Processor functions to run
*/
protected SingleThreadedRunner(DBIDs ids, Processor[] procs) {
super();
this.ids = ids;
this.procs = procs;
}
public void run() {
Processor.Instance[] instances = new Processor.Instance[procs.length];
for(int i = 0; i < procs.length; i++) {
instances[i] = procs[i].instantiate(this);
}
for(DBIDIter iter = ids.iter(); iter.valid(); iter.advance()) {
for(int i = 0; i < instances.length; i++) {
instances[i].map(iter);
}
}
for(int i = 0; i < instances.length; i++) {
procs[i].cleanup(instances[i]);
}
}
@Override
public > I getInstance(SharedVariable parent) {
@SuppressWarnings("unchecked")
I inst = (I) variables.get(parent);
if(inst == null) {
inst = parent.instantiate();
variables.put(parent, inst);
}
return inst;
}
}
}