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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; import org.apache.cassandra.config.CFMetaData; import org.apache.cassandra.config.DatabaseDescriptor; import org.apache.cassandra.db.DataRange; import org.apache.cassandra.db.DecoratedKey; import org.apache.cassandra.db.RowPosition; import org.apache.cassandra.dht.IPartitioner; import org.apache.cassandra.dht.Murmur3Partitioner; import org.apache.cassandra.dht.Token; import org.apache.lucene.document.Document; import org.apache.lucene.document.Field; import org.apache.lucene.search.Query; import org.apache.lucene.search.SortField; /** * Class for several row partitioning {@link Token} mappings between Cassandra and Lucene. * * @author Andres de la Pena <adelapena@stratio.com> */ public abstract class TokenMapper { /** The column family metadata. */ protected final CFMetaData metadata; /** * Returns a new {@link TokenMapper} instance for the current partitioner using the specified column family * metadata. * * @param metadata The column family metadata. * @return A new {@link TokenMapper} instance for the current partitioner. */ public static TokenMapper instance(CFMetaData metadata) { IPartitioner partitioner = DatabaseDescriptor.getPartitioner(); if (partitioner instanceof Murmur3Partitioner) { return new TokenMapperMurmur(metadata); } else { return new TokenMapperGeneric(metadata); } } /** * Builds a new {@link TokenMapper} instance for the current partitioner using the specified column family * metadata. * * @param metadata The column family metadata. */ public TokenMapper(CFMetaData metadata) { this.metadata = metadata; } /** * Adds to the specified {@link Document} the {@link Field}s associated to the token of the specified row key. * * @param document A {@link Document}. * @param partitionKey The raw partition key to be added. */ public abstract void addFields(Document document, DecoratedKey partitionKey); /** * Returns a Lucene {@link Query} for filtering documents/rows according to the row token range specified in {@code * dataRange}. * * @param dataRange The key range containing the row token range to be filtered. * @return A Lucene {@link Query} for filtering documents/rows according to the row token range specified in {@code * dataRage}. */ public Query query(DataRange dataRange) { RowPosition startPosition = dataRange.startKey(); RowPosition stopPosition = dataRange.stopKey(); Token start = startPosition.getToken(); Token stop = stopPosition.getToken(); boolean includeLower = includeStart(startPosition); boolean includeUpper = includeStop(stopPosition); return query(start, stop, includeLower, includeUpper); } /** * Returns a Lucene {@link Query} for retrieving the documents inside the specified {@link Token} range. * * @param lower The lower accepted {@link Token}. Maybe null meaning no lower limit. * @param upper The upper accepted {@link Token}. Maybe null meaning no lower limit. * @param includeLower If the {@code lowerValue} is included in the range. * @param includeUpper If the {@code upperValue} is included in the range. * @return A Lucene {@link Query} for retrieving the documents inside the specified {@link Token} range. */ @SuppressWarnings("unchecked") public Query query(Token lower, Token upper, boolean includeLower, boolean includeUpper) { if (lower != null && upper != null && isMinimum(lower) && isMinimum(upper) && (includeLower || includeUpper)) { return null; } else { return makeQuery(lower, upper, includeLower, includeUpper); } } /** * Returns {@code true} if the specified {@link Token} is the minimum accepted by the {@link IPartitioner}, {@code * false} otherwise. * * @param token A {@link Token}. * @return {@code true} if the specified {@link Token} is the minimum accepted by the {@link IPartitioner}, {@code * false} otherwise. */ public boolean isMinimum(Token token) { Token minimum = DatabaseDescriptor.getPartitioner().getMinimumToken(); return token.compareTo(minimum) == 0; } /** * Returns a Lucene {@link Query} for retrieving the documents with the specified {@link Token}. * * @param token A {@link Token}. * @return A Lucene {@link Query} for retrieving the documents with the specified {@link Token}. */ public abstract Query query(Token token); /** * Returns a Lucene {@link Query} for retrieving the documents inside the specified {@link Token} range. * * @param lower The lower accepted {@link Token}. Maybe null meaning no lower limit. * @param upper The upper accepted {@link Token}. Maybe null meaning no lower limit. * @param includeLower If the {@code lowerValue} is included in the range. * @param includeUpper If the {@code upperValue} is included in the range. * @return A Lucene {@link Query} for retrieving the documents inside the specified {@link Token} range. */ protected abstract Query makeQuery(Token lower, Token upper, boolean includeLower, boolean includeUpper); /** * Returns a Lucene {@link SortField} array for sorting documents/rows according to the current partitioner. * * @return A Lucene {@link SortField} array for sorting documents/rows according to the current partitioner. */ public abstract SortField[] sortFields(); /** * Returns {@code true} if the specified lower row position kind must be included in the filtered range, {@code * false} otherwise. * * @param rowPosition A {@link RowPosition}. * @return {@code true} if the specified lower row position kind must be included in the filtered range, {@code * false} otherwise. */ public boolean includeStart(RowPosition rowPosition) { switch (rowPosition.kind()) { case MAX_BOUND: return false; case MIN_BOUND: return true; case ROW_KEY: return true; default: throw new IllegalArgumentException(); } } /** * Returns {@code true} if the specified upper row position kind must be included in the filtered range, {@code * false} otherwise. * * @param rowPosition A {@link RowPosition}. * @return {@code true} if the specified upper row position kind must be included in the filtered range, {@code * false} otherwise. */ public boolean includeStop(RowPosition rowPosition) { switch (rowPosition.kind()) { case MAX_BOUND: return true; case MIN_BOUND: return false; case ROW_KEY: return true; default: throw new IllegalArgumentException(); } } }