Github user sounakr commented on a diff in the pull request: https://github.com/apache/carbondata/pull/1359#discussion_r143721417 --- Diff: examples/spark2/src/main/scala/org/apache/carbondata/examples/MinMaxDataMapFactory.java --- @@ -0,0 +1,157 @@ +/* + * 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 org.apache.carbondata.examples; + +import java.io.IOException; +import java.util.ArrayList; +import java.util.Arrays; +import java.util.HashMap; +import java.util.List; +import java.util.Map; + +import org.apache.carbondata.core.cache.Cache; +import org.apache.carbondata.core.cache.CacheProvider; +import org.apache.carbondata.core.cache.CacheType; +import org.apache.carbondata.core.datamap.DataMapDistributable; +import org.apache.carbondata.core.datamap.DataMapMeta; +import org.apache.carbondata.core.datamap.TableDataMap; +import org.apache.carbondata.core.datamap.dev.DataMap; +import org.apache.carbondata.core.datamap.dev.DataMapFactory; +import org.apache.carbondata.core.datamap.dev.DataMapWriter; +import org.apache.carbondata.core.datastore.filesystem.CarbonFile; +import org.apache.carbondata.core.datastore.filesystem.CarbonFileFilter; +import org.apache.carbondata.core.datastore.impl.FileFactory; +import org.apache.carbondata.core.events.ChangeEvent; +import org.apache.carbondata.core.indexstore.TableBlockIndexUniqueIdentifier; +import org.apache.carbondata.core.indexstore.blockletindex.BlockletDataMap; +import org.apache.carbondata.core.indexstore.schema.FilterType; +import org.apache.carbondata.core.memory.MemoryException; +import org.apache.carbondata.core.metadata.AbsoluteTableIdentifier; + + +/** + * Min Max DataMap Factory + */ +public class MinMaxDataMapFactory implements DataMapFactory { + + private AbsoluteTableIdentifier identifier; + + // segmentId -> list of index file + private Map<String, List<TableBlockIndexUniqueIdentifier>> segmentMap = new HashMap<>(); + + @Override + public void init(AbsoluteTableIdentifier identifier, String dataMapName) { + this.identifier = identifier; + } + + /** + * createWriter will return the MinMaxDataWriter. + * @param segmentId + * @return + */ + @Override + public DataMapWriter createWriter(String segmentId) { + return new MinMaxDataWriter(); + } + + /** + * getDataMaps Factory method Initializes the Min Max Data Map and returns. + * @param segmentId + * @return + * @throws IOException + */ + @Override + public List<DataMap> getDataMaps(String segmentId) throws IOException { + List<TableBlockIndexUniqueIdentifier> tableBlockIndexUniqueIdentifiers = + segmentMap.get(segmentId); + List<DataMap> dataMapList = new ArrayList<>(); + if (tableBlockIndexUniqueIdentifiers == null) { + tableBlockIndexUniqueIdentifiers = new ArrayList<>(); + CarbonFile[] listFiles = getCarbonIndexFiles(segmentId); + for (int i = 0; i < listFiles.length; i++) { + tableBlockIndexUniqueIdentifiers.add( + new TableBlockIndexUniqueIdentifier(identifier, segmentId, listFiles[i].getName())); + } + } + // Form a dataMap of Type MinMaxDataMap. + MinMaxDataMap dataMap = new MinMaxDataMap(); + try { + dataMap.init(tableBlockIndexUniqueIdentifiers.get(0).getFilePath()); + } catch (MemoryException ex) { + + } + dataMapList.add(dataMap); + return dataMapList; + } + + /** + * Routine to retrieve the carbonIndex. + * @param segmentId + * @return + */ + private CarbonFile[] getCarbonIndexFiles(String segmentId) { --- End diff -- removed
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