filters.indexing.IndexableFilter.java Source code

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Here is the source code for filters.indexing.IndexableFilter.java

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// The MIT License
//
// Copyright (c) 2010 Stelios Karabasakis
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
//
package filters.indexing;

import indexing.ReviewTermPayload;
import indexing.Token;
import java.io.IOException;
import org.apache.lucene.analysis.TokenFilter;
import org.apache.lucene.analysis.TokenStream;
import org.apache.lucene.analysis.tokenattributes.FlagsAttribute;
import org.apache.lucene.analysis.tokenattributes.PayloadAttribute;
import org.apache.lucene.analysis.tokenattributes.TermAttribute;
import org.apache.lucene.analysis.tokenattributes.TypeAttribute;

/**
 * TODO Description missing
 * @author Stelios Karabasakis
 */
public class IndexableFilter extends TokenFilter {

    private boolean set_synset_terms = false;

    private TermAttribute input_term;
    private TypeAttribute input_type;
    private FlagsAttribute input_flags;
    private PayloadAttribute input_payload;
    private TermAttribute output_term;
    private TypeAttribute output_type;
    private FlagsAttribute output_flags;
    private PayloadAttribute output_payload;

    /**
     * Constructor for class IndexableFilter
     * @param input
     */
    public IndexableFilter(TokenStream input, boolean set_synset_terms) {
        super(input);

        // Getting attributes from input token stream
        input_term = input.getAttribute(TermAttribute.class);
        input_type = input.getAttribute(TypeAttribute.class);
        input_flags = input.getAttribute(FlagsAttribute.class);
        input_payload = input.getAttribute(PayloadAttribute.class);

        // Setting attributes for this token stream
        output_term = this.addAttribute(TermAttribute.class);
        output_type = this.addAttribute(TypeAttribute.class);
        output_flags = this.addAttribute(FlagsAttribute.class);
        output_payload = input.addAttribute(PayloadAttribute.class);

        this.set_synset_terms = set_synset_terms;
    }

    /* (non-Javadoc)
     * @see org.apache.lucene.analysis.TokenStream#incrementToken()
     */
    @Override
    public boolean incrementToken() throws IOException {
        Token current_token;
        while ((current_token = getNextToken()) != null) {
            if (current_token.isIndexable()) {
                if (set_synset_terms) {
                    if (current_token.isLemmatized()) {
                        output_term.setTermBuffer(current_token.synset().toString());
                        output_type.setType(current_token.term);
                    } else {
                        output_term.setTermBuffer(current_token.term);
                        output_type.setType(current_token.term);
                    }
                } else {
                    output_term.setTermBuffer(current_token.term);
                    output_type.setType(current_token.synset().toString());
                }
                output_flags.setFlags(current_token.flags);
                output_payload.setPayload(current_token.payload.getPayload());

                return true;
            }
        }

        return false;
    }

    private Token getNextToken() throws IOException {
        if (input.incrementToken())
            return new Token(input_term.term(), input_type.type(), input_flags.getFlags(),
                    new ReviewTermPayload(input_payload.getPayload()));
        else
            return null;
    }
}