/*
* LensKit, an open source recommender systems toolkit.
* Copyright 2010-2014 LensKit Contributors. See CONTRIBUTORS.md.
* Work on LensKit has been funded by the National Science Foundation under
* grants IIS 05-34939, 08-08692, 08-12148, and 10-17697.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 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 General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc., 51
* Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
package org.grouplens.lenskit.eval.algorithm;
import com.google.common.base.Joiner;
import com.google.common.collect.ImmutableMap;
import org.grouplens.grapht.Component;
import org.grouplens.grapht.Dependency;
import org.grouplens.grapht.ResolutionException;
import org.grouplens.grapht.graph.DAGNode;
import org.grouplens.lenskit.RecommenderBuildException;
import org.grouplens.lenskit.core.*;
import org.grouplens.lenskit.eval.Attributed;
import org.grouplens.lenskit.eval.script.BuiltBy;
import org.grouplens.lenskit.inject.RecommenderGraphBuilder;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import java.util.Collections;
import java.util.Map;
import java.util.Random;
/**
* An instance of a recommender algorithmInfo to be benchmarked.
*
* @author <a href="http://www.grouplens.org">GroupLens Research</a>
*/
@BuiltBy(AlgorithmInstanceBuilder.class)
public class AlgorithmInstance implements Attributed {
private static final Logger logger = LoggerFactory.getLogger(AlgorithmInstance.class);
@Nullable
private final String algoName;
@Nonnull
private final LenskitConfiguration config;
@Nonnull
private final Map<String, Object> attributes;
private final boolean preload;
private Random random;
public AlgorithmInstance(String name, LenskitConfiguration config) {
this(name, config, Collections.<String, Object>emptyMap(), false);
}
public AlgorithmInstance(String name, LenskitConfiguration cfg, Map<String, Object> attrs, boolean preload) {
algoName = name;
config = new LenskitConfiguration(cfg);
attributes = ImmutableMap.copyOf(attrs);
this.preload = preload;
}
/**
* Get the name of this algorithmInfo. This returns a short name which is
* used to identify the algorithmInfo or instance.
*
* @return The algorithmInfo's name
*/
@Override
public String getName() {
return algoName;
}
/**
* Query whether this algorithmInfo is to operate on in-memory data.
*
* @return {@code true} if the ratings database should be loaded in-memory
* prior to running.
*/
public boolean getPreload() {
return preload;
}
@Override
@Nonnull
public Map<String, Object> getAttributes() {
return attributes;
}
@Nonnull
public LenskitConfiguration getConfig() {
return config;
}
/**
* Let AlgorithmInstanceBuilder to pass random number generator to algorithmInfo instance
*
* @param rng The random number generator.
* @return The new algorithmInfo instance
*/
public AlgorithmInstance setRandom(Random rng) {
random = rng;
return this;
}
/**
* Build a recommender.
* @param defaults Additional configuration. This configuration comes <em>before</em> the
* algorithm's configuration, so it is overridden if appropriate.
* @return
* @throws RecommenderBuildException
*/
public LenskitRecommender buildRecommender(LenskitConfiguration defaults) throws RecommenderBuildException {
LenskitRecommenderEngineBuilder builder = LenskitRecommenderEngine.newBuilder();
if (defaults != null) {
builder.addConfiguration(defaults);
}
builder.addConfiguration(config);
return builder.build().createRecommender();
}
/**
* Build a recommender graph (but don't instantiate any objects).
*
*
* @param defaults Additional configuration. This configuration comes <em>before</em> the
* algorithm's configuration, so it is overridden if appropriate.
* @return The recommender graph.
* @throws RecommenderConfigurationException if there is an error configuring the recommender.
*/
public DAGNode<Component,Dependency> buildRecommenderGraph(LenskitConfiguration defaults) throws RecommenderConfigurationException {
LenskitRecommenderEngineBuilder builder = LenskitRecommenderEngine.newBuilder();
if (defaults != null) {
builder.addConfiguration(defaults);
}
builder.addConfiguration(config);
RecommenderGraphBuilder rgb = new RecommenderGraphBuilder();
rgb.addConfiguration(defaults);
rgb.addConfiguration(config);
try {
return rgb.buildGraph();
} catch (ResolutionException e) {
throw new RecommenderConfigurationException("error configuring recommender", e);
}
}
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append("LenskitAlgorithm(")
.append(getName())
.append(")");
if (!attributes.isEmpty()) {
sb.append("[");
Joiner.on(", ")
.withKeyValueSeparator("=")
.appendTo(sb, attributes);
sb.append("]");
}
return sb.toString();
}
}