com.stratio.cassandra.index.query.Condition.java Source code

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Here is the source code for com.stratio.cassandra.index.query.Condition.java

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/*
 * Copyright 2014, Stratio.
 *
 * Licensed 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 com.stratio.cassandra.index.query;

import com.stratio.cassandra.index.schema.ColumnMapper;
import com.stratio.cassandra.index.schema.Schema;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.TokenStream;
import org.apache.lucene.analysis.tokenattributes.TermToBytesRefAttribute;
import org.apache.lucene.search.Filter;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.QueryWrapperFilter;
import org.apache.lucene.util.BytesRef;
import org.apache.lucene.util.IOUtils;
import org.codehaus.jackson.annotate.JsonCreator;
import org.codehaus.jackson.annotate.JsonProperty;
import org.codehaus.jackson.annotate.JsonSubTypes;
import org.codehaus.jackson.annotate.JsonTypeInfo;

import java.io.IOException;

/**
 * The abstract base class for queries.
 * <p/>
 * Known subclasses are: <ul> <li> {@link BooleanCondition} <li> {@link FuzzyCondition} <li> {@link MatchCondition} <li>
 * {@link PhraseCondition} <li> {@link PrefixCondition} <li> {@link RangeCondition} <li> {@link WildcardCondition}
 * </ul>
 *
 * @author Andres de la Pena <adelapena@stratio.com>
 */
@JsonTypeInfo(use = JsonTypeInfo.Id.NAME, include = JsonTypeInfo.As.PROPERTY, property = "type")
@JsonSubTypes({ @JsonSubTypes.Type(value = BooleanCondition.class, name = "boolean"),
        @JsonSubTypes.Type(value = FuzzyCondition.class, name = "fuzzy"),
        @JsonSubTypes.Type(value = LuceneCondition.class, name = "lucene"),
        @JsonSubTypes.Type(value = MatchCondition.class, name = "match"),
        @JsonSubTypes.Type(value = RangeCondition.class, name = "range"),
        @JsonSubTypes.Type(value = PhraseCondition.class, name = "phrase"),
        @JsonSubTypes.Type(value = PrefixCondition.class, name = "prefix"),
        @JsonSubTypes.Type(value = RegexpCondition.class, name = "regexp"),
        @JsonSubTypes.Type(value = WildcardCondition.class, name = "wildcard"), })
public abstract class Condition {
    /** The default boost to be used. */
    public static final float DEFAULT_BOOST = 1.0f;

    /** The boost to be used. */
    @JsonProperty("boost")
    protected float boost;

    /**
     * Abstract {@link Condition} builder receiving the boost to be used.
     *
     * @param boost The boost for this query clause. Documents matching this clause will (in addition to the normal
     *              weightings) have their score multiplied by {@code boost}.
     */
    @JsonCreator
    public Condition(@JsonProperty("boost") Float boost) {
        this.boost = boost == null ? DEFAULT_BOOST : boost;
    }

    /**
     * Returns the Lucene {@link Query} representation of this condition.
     *
     * @param schema The schema to be used.
     * @return The Lucene {@link Query} representation of this condition.
     */
    public abstract Query query(Schema schema);

    /**
     * Returns the Lucene {@link Filter} representation of this condition.
     *
     * @param schema The schema to be used.
     * @return The Lucene {@link Filter} representation of this condition.
     */
    public Filter filter(Schema schema) {
        return new QueryWrapperFilter(query(schema));
    }

    protected String analyze(String field, String value, ColumnMapper<?> columnMapper) {
        TokenStream source = null;
        try {
            Analyzer analyzer = columnMapper.analyzer();
            source = analyzer.tokenStream(field, value);
            source.reset();

            TermToBytesRefAttribute termAtt = source.getAttribute(TermToBytesRefAttribute.class);
            BytesRef bytes = termAtt.getBytesRef();

            if (!source.incrementToken()) {
                return null;
            }
            termAtt.fillBytesRef();
            if (source.incrementToken()) {
                throw new IllegalArgumentException("analyzer returned too many terms for multiTerm term: " + value);
            }
            source.end();
            return BytesRef.deepCopyOf(bytes).utf8ToString();
        } catch (IOException e) {
            throw new RuntimeException("Error analyzing multiTerm term: " + value, e);
        } finally {
            IOUtils.closeWhileHandlingException(source);
        }
    }

}