IcuTransformTokenFilterFactory.java

/*
 * Licensed to ElasticSearch and Shay Banon under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. ElasticSearch 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 org.elasticsearch.index.analysis;

import com.ibm.icu.text.Transliterator;
import org.apache.lucene.analysis.TokenStream;
import org.apache.lucene.analysis.icu.ICUTransformFilter;
import org.elasticsearch.common.inject.Inject;
import org.elasticsearch.common.inject.assistedinject.Assisted;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.index.Index;
import org.elasticsearch.index.settings.IndexSettings;


/**
 */
public class IcuTransformTokenFilterFactory extends AbstractTokenFilterFactory {

    private final String id;
    private final int dir;
    private final Transliterator transliterator;

    @Inject
    public IcuTransformTokenFilterFactory(Index index, @IndexSettings Settings indexSettings, @Assisted String name, @Assisted Settings settings) {
        super(index, indexSettings, name, settings);
        this.id = settings.get("id", "Null");
        String s = settings.get("dir", "forward");
        this.dir = "forward".equals(s) ? Transliterator.FORWARD : Transliterator.REVERSE;
        this.transliterator = Transliterator.getInstance(id, dir);
    }

    @Override
    public TokenStream create(TokenStream tokenStream) {
        return new ICUTransformFilter(tokenStream, transliterator);
    }
}