org.jpmml.runtime.ModelManagerCache.java Source code

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Here is the source code for org.jpmml.runtime.ModelManagerCache.java

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/*
 * Copyright (c) 2014 Villu Ruusmann
 *
 * This file is part of JPMML-Evaluator
 *
 * JPMML-Evaluator 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.
 *
 * JPMML-Evaluator 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 JPMML-Evaluator.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.jpmml.runtime;

import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.util.concurrent.ConcurrentMap;

import javax.xml.bind.JAXBException;
import javax.xml.transform.sax.SAXSource;

import com.google.common.cache.CacheBuilder;
import com.google.common.cache.CacheLoader;
import com.google.common.cache.LoadingCache;
import org.dmg.pmml.Model;
import org.dmg.pmml.PMML;
import org.jpmml.manager.ModelManager;
import org.jpmml.manager.ModelManagerFactory;
import org.jpmml.manager.PMMLManager;
import org.jpmml.model.ImportFilter;
import org.jpmml.model.JAXBUtil;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;

abstract public class ModelManagerCache {

    private ModelManagerFactory modelManagerFactory = null;

    private LoadingCache<Class<?>, ModelManager<? extends Model>> cache = null;

    public ModelManagerCache(ModelManagerFactory modelManagerFactory, CacheBuilder<Object, Object> cacheBuilder) {
        setModelEvaluatorFactory(modelManagerFactory);

        CacheLoader<Class<?>, ModelManager<? extends Model>> cacheLoader = new CacheLoader<Class<?>, ModelManager<? extends Model>>() {

            @Override
            public ModelManager<? extends Model> load(Class<?> clazz) throws Exception {
                return ModelManagerCache.this.loadModelManager(clazz);
            }
        };

        this.cache = cacheBuilder.build(cacheLoader);
    }

    public ModelManager<? extends Model> get(Class<?> clazz) throws Exception {
        return this.cache.get(clazz);
    }

    public void remove(Class<?> clazz) {
        this.cache.invalidate(clazz);
    }

    public ConcurrentMap<Class<?>, ModelManager<? extends Model>> asMap() {
        return this.cache.asMap();
    }

    protected ModelManager<? extends Model> loadModelManager(Class<?> clazz)
            throws IOException, JAXBException, SAXException {
        String path = (clazz.getName()).replace('.', '/') + ".pmml";

        ClassLoader clazzLoader = clazz.getClassLoader();

        InputStream is = clazzLoader.getResourceAsStream(path);
        if (is == null) {
            throw new FileNotFoundException(path);
        }

        PMML pmml;

        try {
            InputSource source = new InputSource(is);

            // Transform a PMML schema version 3.X or 4.X document to a PMML schema version 4.2 document
            SAXSource transformedSource = ImportFilter.apply(source);

            pmml = JAXBUtil.unmarshalPMML(transformedSource);
        } finally {
            is.close();
        }

        pmml = process(pmml);

        PMMLManager pmmlManager = new PMMLManager(pmml);

        ModelManagerFactory modelManagerFactory = getModelManagerFactory();

        return pmmlManager.getModelManager(modelManagerFactory);
    }

    protected PMML process(PMML pmml) {
        return pmml;
    }

    public ModelManagerFactory getModelManagerFactory() {
        return this.modelManagerFactory;
    }

    private void setModelEvaluatorFactory(ModelManagerFactory modelManagerFactory) {
        this.modelManagerFactory = modelManagerFactory;
    }
}