| /* |
| * 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.arrow.vector.complex; |
| |
| import org.apache.arrow.util.Preconditions; |
| import org.apache.arrow.vector.UInt4Vector; |
| |
| /** |
| * A helper class that is used to track and populate empty values in repeated value vectors. |
| */ |
| public class EmptyValuePopulator { |
| private final UInt4Vector offsets; |
| |
| public EmptyValuePopulator(UInt4Vector offsets) { |
| this.offsets = Preconditions.checkNotNull(offsets, "offsets cannot be null"); |
| } |
| |
| /** |
| * Marks all values since the last set as empty. The last set value is obtained from underlying offsets vector. |
| * |
| * @param lastIndex the last index (inclusive) in the offsets vector until which empty population takes place |
| * @throws java.lang.IndexOutOfBoundsException if lastIndex is negative or greater than offsets capacity. |
| */ |
| public void populate(int lastIndex) { |
| if (lastIndex < 0) { |
| throw new IndexOutOfBoundsException("index cannot be negative"); |
| } |
| final int lastSet = Math.max(offsets.getValueCount() - 1, 0); |
| final int previousEnd = offsets.get(lastSet);//0 ? 0 : accessor.get(lastSet); |
| for (int i = lastSet; i < lastIndex; i++) { |
| offsets.setSafe(i + 1, previousEnd); |
| } |
| offsets.setValueCount(lastIndex + 1); |
| } |
| |
| } |