001/* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, software 013 * distributed under the License is distributed on an "AS IS" BASIS, 014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 015 * See the License for the specific language governing permissions and 016 * limitations under the License. 017 */ 018package org.apache.hadoop.hbase.types; 019 020import org.apache.hadoop.hbase.util.Order; 021import org.apache.hadoop.hbase.util.PositionedByteRange; 022import org.apache.yetus.audience.InterfaceAudience; 023 024/** 025 * The {@code Union} family of {@link DataType}s encode one of a fixed collection of Objects. They 026 * provide convenience methods which handle type casting on your behalf. 027 * @see Union2 028 */ 029@SuppressWarnings("unchecked") 030@InterfaceAudience.Public 031public abstract class Union3<A, B, C> extends Union2<A, B> { 032 033 protected final DataType<C> typeC; 034 035 /** 036 * Create an instance of {@code Union3} over the set of specified types. 037 */ 038 public Union3(DataType<A> typeA, DataType<B> typeB, DataType<C> typeC) { 039 super(typeA, typeB); 040 this.typeC = typeC; 041 } 042 043 @Override 044 public boolean isOrderPreserving() { 045 return super.isOrderPreserving() && typeC.isOrderPreserving(); 046 } 047 048 @Override 049 public Order getOrder() { 050 return null; 051 } 052 053 @Override 054 public boolean isNullable() { 055 return super.isNullable() && typeC.isNullable(); 056 } 057 058 @Override 059 public boolean isSkippable() { 060 return super.isSkippable() && typeC.isSkippable(); 061 } 062 063 /** 064 * Read an instance of the third type parameter from buffer {@code src}. 065 */ 066 public C decodeC(PositionedByteRange src) { 067 return (C) decode(src); 068 } 069}