net.phoenix.nlp.pos.chmm.recognitor.DateTimeRecognitor.java Source code

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Here is the source code for net.phoenix.nlp.pos.chmm.recognitor.DateTimeRecognitor.java

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/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package net.phoenix.nlp.pos.chmm.recognitor;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

import net.phoenix.nlp.Nature;
import net.phoenix.nlp.corpus.CorpusRepository;
import net.phoenix.nlp.pos.chmm.POSTerm;
import net.phoenix.nlp.pos.chmm.TermEdge;
import net.phoenix.nlp.pos.chmm.TermGraph;
import net.phoenix.nlp.pos.chmm.TermPath;
import net.phoenix.nlp.pos.chmm.corpus.CharsetCorpus;
import net.phoenix.nlp.pos.chmm.corpus.file.CharsetFileCorpus;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * Jigsaw server  198711135012??
 * 
 * @author <a href="shamphone@gmail.com">Li XiongFeng</a>
 * @date 2013-2-3
 * @version 1.0.0
 */
public class DateTimeRecognitor extends AbstractRecognitor {

    private static Log log = LogFactory.getLog(DateTimeRecognitor.class);

    enum Status {
        Number, Date, Qualifier, Other
    };

    private char[] numbers;
    private char[] qualifiers;

    public DateTimeRecognitor(CorpusRepository dictionary) throws IOException {
        super(dictionary);
        CharsetCorpus chars = dictionary.getCorpus(CharsetFileCorpus.class);
        this.numbers = chars.getChars("datetime.number");
        Arrays.sort(this.numbers);
        this.qualifiers = chars.getChars("datetime.qualifier");
        Arrays.sort(this.qualifiers);
        log.info("DateTimeRecognitor ready.");
    }

    @Override
    public void recognize(TermGraph graph) {
        this.resetEdgesScore(graph, 0.0);
        // ????;
        // ??????
        List<POSTerm> currentVertexes = new ArrayList<POSTerm>(graph.vertexSet());
        for (POSTerm start : currentVertexes) {
            // ???length???
            Status status = this.parseStatus(start);
            if (status != Status.Other) {
                TermPath candidate = graph.createPath(start);
                this.findDateTime(graph, candidate, status);
            }

        }

    }

    private Status parseStatus(POSTerm term) {
        if (term.getTermNatures().isNature(Nature.Number))
            return Status.Number;
        String name = term.getName();
        name = name.trim();
        if (name.length() == 0)
            return Status.Other;
        // ?
        if (name.length() == 1) {
            if (Arrays.binarySearch(this.qualifiers, name.charAt(0)) >= 0)
                return Status.Qualifier;
            else if (Arrays.binarySearch(this.numbers, name.charAt(0)) >= 0)
                return Status.Number;
            else
                return Status.Other;
        }

        // + //?
        boolean isNumber = true;
        int pos = 0;
        // 
        while (isNumber && pos < name.length() - 1) {
            isNumber = (Arrays.binarySearch(this.numbers, name.charAt(pos)) >= 0);
            pos++;
        }
        if (isNumber) {
            if (Arrays.binarySearch(this.qualifiers, name.charAt(pos)) >= 0)
                return Status.Date;
            else if (Arrays.binarySearch(this.numbers, name.charAt(pos)) >= 0)
                return Status.Number;
            else
                return Status.Other;
        }

        return Status.Other;
    }

    /**
     * ????length?
     * 
     * @param graph
     *            ?
     * @param partName
     *            ???????
     * @param length
     *            ???
     * @param names
     *            ??
     */
    private void findDateTime(TermGraph graph, TermPath partName, Status currentStatus) {
        // int pos = partName.getVertexCount();
        POSTerm current = partName.getEndVertex();
        for (TermEdge edge : graph.outgoingEdgesOf(current)) {
            // N???N+1?????
            // ?????N
            POSTerm next = graph.getEdgeTarget(edge);
            Status nextStatus = this.parseStatus(next);
            boolean canContinue = false;
            switch (currentStatus) {
            case Number:
                canContinue = (nextStatus.equals(Status.Qualifier) || nextStatus.equals(Status.Date));
                break;
            case Qualifier:
            case Date:
                canContinue = nextStatus.equals(Status.Number) || nextStatus.equals(Status.Date);
                break;
            default:
                canContinue = false;
            }
            if (canContinue) {
                partName.extend(edge);
                this.findDateTime(graph, partName, nextStatus);
                partName.removeEnd();
            } else {
                this.checkDateTime(graph, partName);
            }
        }

    }

    /**
     * foundnumber
     * 
     * @param graph
     * @param found
     * @param numbers
     */
    private void checkDateTime(TermGraph graph, TermPath partName) {
        if (partName.getVertexCount() == 1) {
            return;
        }
        this.createMergedTerm(graph, partName, this.createTermNatures(Nature.Time), false);
        // log.info(term + " found!");
    }

}