Github user ravipesala commented on a diff in the pull request:
https://github.com/apache/carbondata/pull/1359#discussion_r143711222
--- 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 --
why this method required
---
Locked
