org.jpmml.pig.PMMLUtil.java Source code

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Here is the source code for org.jpmml.pig.PMMLUtil.java

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

import java.io.IOException;
import java.util.List;
import java.util.Map;

import com.google.common.cache.CacheBuilder;
import com.google.common.collect.Lists;
import com.google.common.collect.Maps;
import org.apache.pig.backend.executionengine.ExecException;
import org.apache.pig.data.DataType;
import org.apache.pig.data.Tuple;
import org.apache.pig.data.TupleFactory;
import org.apache.pig.impl.logicalLayer.schema.Schema;
import org.apache.pig.impl.logicalLayer.schema.Schema.FieldSchema;
import org.dmg.pmml.DataField;
import org.dmg.pmml.FieldName;
import org.dmg.pmml.OutputField;
import org.jpmml.evaluator.Evaluator;
import org.jpmml.evaluator.EvaluatorUtil;
import org.jpmml.evaluator.FieldValue;
import org.jpmml.evaluator.ModelEvaluator;
import org.jpmml.evaluator.OutputUtil;
import org.jpmml.runtime.ModelEvaluatorCache;

public class PMMLUtil {

    private PMMLUtil() {
    }

    static public Object evaluateSimple(Class<?> clazz, Tuple tuple) throws IOException {

        if (tuple == null) {
            return null;
        }

        Evaluator evaluator = getEvaluator(clazz);

        Map<FieldName, FieldValue> arguments = loadArguments(evaluator, tuple);

        Map<FieldName, ?> result = evaluator.evaluate(arguments);

        Object targetValue = result.get(evaluator.getTargetField());

        return EvaluatorUtil.decode(targetValue);
    }

    static public Tuple evaluateComplex(Class<?> clazz, Tuple tuple) throws IOException {

        if (tuple == null) {
            return null;
        }

        Evaluator evaluator = getEvaluator(clazz);

        Map<FieldName, FieldValue> arguments = loadArguments(evaluator, tuple);

        Map<FieldName, ?> result = evaluator.evaluate(arguments);

        return storeResult(evaluator, result);
    }

    static public Schema getResultType(Class<?> clazz) {
        Evaluator evaluator;

        try {
            evaluator = getEvaluator(clazz);
        } catch (IOException ioe) {
            return null;
        }

        Schema tuple = new Schema();

        List<FieldName> targetFields = evaluator.getTargetFields();
        for (FieldName targetField : targetFields) {
            DataField field = evaluator.getDataField(targetField);

            org.dmg.pmml.DataType dataType = field.getDataType();

            tuple.add(new FieldSchema(targetField.getValue(), getDataType(dataType)));
        }

        List<FieldName> outputFields = evaluator.getOutputFields();
        for (FieldName outputField : outputFields) {
            OutputField field = evaluator.getOutputField(outputField);

            org.dmg.pmml.DataType dataType = OutputUtil.getDataType(field, (ModelEvaluator<?>) evaluator);

            tuple.add(new FieldSchema(outputField.getValue(), getDataType(dataType)));
        }

        Schema result = new Schema();
        result.add(new FieldSchema((String) null, tuple));

        return result;
    }

    static private Map<FieldName, FieldValue> loadArguments(Evaluator evaluator, Tuple tuple) throws ExecException {

        if (tuple.size() == 1) {
            byte type = tuple.getType(0);

            switch (type) {
            case DataType.TUPLE:
                return loadPrimitiveList(evaluator, (Tuple) tuple.get(0));
            default:
                break;
            }
        }

        return loadPrimitiveList(evaluator, tuple);
    }

    static private Map<FieldName, FieldValue> loadPrimitiveList(Evaluator evaluator, Tuple tuple)
            throws ExecException {
        Map<FieldName, FieldValue> result = Maps.newLinkedHashMap();

        List<FieldName> activeFields = evaluator.getActiveFields();
        if (activeFields.size() != tuple.size()) {
            throw new ExecException();
        }

        int i = 0;

        for (FieldName activeField : activeFields) {
            Object object = tuple.get(i);

            FieldValue value = EvaluatorUtil.prepare(evaluator, activeField, object);

            result.put(activeField, value);

            i++;
        }

        return result;
    }

    static private Tuple storeResult(Evaluator evaluator, Map<FieldName, ?> result) {
        List<Object> values = Lists.newArrayList();

        List<FieldName> targetFields = evaluator.getTargetFields();
        for (FieldName targetField : targetFields) {
            values.add(EvaluatorUtil.decode(result.get(targetField)));
        }

        List<FieldName> outputFields = evaluator.getOutputFields();
        for (FieldName outputField : outputFields) {
            values.add(result.get(outputField));
        }

        TupleFactory tupleFactory = TupleFactory.getInstance();

        return tupleFactory.newTuple(values);
    }

    static private byte getDataType(org.dmg.pmml.DataType dataType) {

        switch (dataType) {
        case STRING:
            return DataType.CHARARRAY;
        case INTEGER:
            return DataType.INTEGER;
        case FLOAT:
            return DataType.FLOAT;
        case DOUBLE:
            return DataType.DOUBLE;
        case BOOLEAN:
            return DataType.BOOLEAN;
        default:
            return DataType.ERROR;
        }
    }

    static private Evaluator getEvaluator(Class<?> clazz) throws IOException {

        try {
            return PMMLUtil.evaluatorCache.get(clazz);
        } catch (Exception e) {
            throw new IOException(e);
        }
    }

    private static final ModelEvaluatorCache evaluatorCache = new ModelEvaluatorCache(CacheBuilder.newBuilder());
}