Github user kumarvishal09 commented on a diff in the pull request:
https://github.com/apache/carbondata/pull/2654#discussion_r214504900
--- Diff:
core/src/main/java/org/apache/carbondata/core/datastore/columnar/BlockIndexerStorage.java
---
@@ -0,0 +1,90 @@
+/*
+ * 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.core.datastore.columnar;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import org.apache.carbondata.core.constants.CarbonCommonConstants;
+
+public class BlockIndexerStorage {
+
+ /**
+ * It compresses depends up on the sequence numbers.
+ * [1,2,3,4,6,8,10,11,12,13] is translated to [1,4,6,8,10,13] and [0,6].
In
+ * first array the start and end of sequential numbers and second array
+ * keeps the indexes of where sequential numbers starts. If there is no
+ * sequential numbers then the same array it returns with empty second
+ * array.
+ *
+ * @param rowIds
+ */
+ public static Map<String, short[]> rleEncodeOnRowId(short[] rowIds,
short[] rowIdPage,
+ short[] rowIdRlePage) {
+ List<Short> list = new
ArrayList<Short>(CarbonCommonConstants.CONSTANT_SIZE_TEN);
+ List<Short> map = new
ArrayList<Short>(CarbonCommonConstants.CONSTANT_SIZE_TEN);
+ int k = 0;
+ int i = 1;
+ for (; i < rowIds.length; i++) {
+ if (rowIds[i] - rowIds[i - 1] == 1) {
+ k++;
+ } else {
+ if (k > 0) {
+ map.add(((short) list.size()));
+ list.add(rowIds[i - k - 1]);
+ list.add(rowIds[i - 1]);
+ } else {
+ list.add(rowIds[i - 1]);
+ }
+ k = 0;
+ }
+ }
+ if (k > 0) {
+ map.add(((short) list.size()));
+ list.add(rowIds[i - k - 1]);
+ list.add(rowIds[i - 1]);
+ } else {
+ list.add(rowIds[i - 1]);
+ }
+ int compressionPercentage = (((list.size() + map.size()) * 100) /
rowIds.length);
+ if (compressionPercentage > 70) {
+ rowIdPage = rowIds;
+ } else {
+ rowIdPage = convertToArray(list);
+ }
+ if (rowIds.length == rowIdPage.length) {
+ rowIdRlePage = new short[0];
+ } else {
+ rowIdRlePage = convertToArray(map);
+ }
+ Map<String, short[]> rowIdAndRowRleIdPages = new HashMap<>(2);
+ rowIdAndRowRleIdPages.put("rowIdPage", rowIdPage);
+ rowIdAndRowRleIdPages.put("rowRlePage", rowIdRlePage);
+ return rowIdAndRowRleIdPages;
+ }
+
+ public static short[] convertToArray(List<Short> list) {
--- End diff --
move this code to carbonutil
---
