| /* |
| * 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.druid.segment; |
| |
| import org.apache.druid.common.config.NullHandling; |
| import org.apache.druid.guice.annotations.PublicApi; |
| import org.apache.druid.query.monomorphicprocessing.RuntimeShapeInspector; |
| |
| import javax.annotation.Nullable; |
| |
| /** |
| * Represents "absent" column. |
| */ |
| @PublicApi |
| public class NilColumnValueSelector implements ColumnValueSelector |
| { |
| private static final NilColumnValueSelector INSTANCE = NullHandling.sqlCompatible() |
| ? new SqlCompatibleNilColumnValueSelector() |
| : new NilColumnValueSelector(); |
| |
| public static NilColumnValueSelector instance() |
| { |
| return INSTANCE; |
| } |
| |
| private NilColumnValueSelector() |
| { |
| } |
| |
| /** |
| * always returns 0, if {@link NullHandling#replaceWithDefault} is set to true, |
| * or always throws an exception, if {@link NullHandling#replaceWithDefault} is |
| * set to false. |
| */ |
| @Override |
| public double getDouble() |
| { |
| return 0.0; |
| } |
| |
| /** |
| * always returns 0.0f, if {@link NullHandling#replaceWithDefault} is set to true, |
| * or always throws an exception, if {@link NullHandling#replaceWithDefault} is |
| * set to false. |
| */ |
| @Override |
| public float getFloat() |
| { |
| return 0.0f; |
| } |
| |
| /** |
| * always returns 0L, if {@link NullHandling#replaceWithDefault} is set to true, |
| * or always throws an exception, if {@link NullHandling#replaceWithDefault} is |
| * set to false. |
| */ |
| @Override |
| public long getLong() |
| { |
| return 0L; |
| } |
| |
| /** |
| * Always returns null. |
| */ |
| @Nullable |
| @Override |
| public Object getObject() |
| { |
| return null; |
| } |
| |
| /** |
| * Returns Object.class. |
| */ |
| @Override |
| public Class classOfObject() |
| { |
| return Object.class; |
| } |
| |
| @Override |
| public boolean isNull() |
| { |
| return true; |
| } |
| |
| @Override |
| public void inspectRuntimeShape(RuntimeShapeInspector inspector) |
| { |
| // nothing to inspect |
| } |
| |
| private static class SqlCompatibleNilColumnValueSelector extends NilColumnValueSelector |
| { |
| @Override |
| public double getDouble() |
| { |
| throw new IllegalStateException("Cannot return null value as double"); |
| } |
| |
| @Override |
| public float getFloat() |
| { |
| throw new IllegalStateException("Cannot return null value as float"); |
| } |
| |
| @Override |
| public long getLong() |
| { |
| throw new IllegalStateException("Cannot return null value as long"); |
| } |
| |
| } |
| } |