| /** |
| * 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.tajo.datum; |
| |
| import org.apache.tajo.common.TajoDataTypes.DataType; |
| import org.apache.tajo.exception.InvalidValueForCastException; |
| import org.apache.tajo.exception.TajoRuntimeException; |
| |
| import static org.apache.tajo.common.TajoDataTypes.Type; |
| |
| public class NullDatum extends Datum { |
| private static NullDatum instance; |
| public static final String DEFAULT_TEXT = "\\\\N"; |
| private static final byte [] EMPTY_BYTES = new byte[0]; |
| private static final DataType NULL_DATA_TYPE; |
| |
| static { |
| instance = new NullDatum(); |
| NULL_DATA_TYPE = DataType.newBuilder().setType(Type.NULL_TYPE).build(); |
| } |
| |
| private NullDatum() { |
| super(Type.NULL_TYPE); |
| } |
| |
| public static NullDatum get() { |
| return instance; |
| } |
| |
| public static DataType getDataType() { |
| return NULL_DATA_TYPE; |
| } |
| |
| @Override |
| public boolean isNull() { |
| return true; |
| } |
| |
| @Override |
| public boolean isNotNull() { |
| return false; |
| } |
| |
| @Override |
| public boolean asBool() { |
| throw new TajoRuntimeException(new InvalidValueForCastException(Type.NULL_TYPE, Type.BOOLEAN)); |
| } |
| |
| @Override |
| public byte asByte() { |
| return 0; |
| } |
| |
| @Override |
| public short asInt2() { |
| return 0; |
| } |
| |
| @Override |
| public int asInt4() { |
| return 0; |
| } |
| |
| @Override |
| public long asInt8() { |
| return 0; |
| } |
| |
| @Override |
| public byte[] asByteArray() { |
| return EMPTY_BYTES; |
| } |
| |
| @Override |
| public float asFloat4() { |
| return 0f; |
| } |
| |
| @Override |
| public double asFloat8() { |
| return 0d; |
| } |
| |
| @Override |
| public String asChars() { |
| return ""; |
| } |
| |
| @Override |
| public byte[] asTextBytes() { |
| return EMPTY_BYTES; |
| } |
| |
| @Override |
| public int size() { |
| return 0; |
| } |
| |
| @Override |
| public boolean equals(Object obj) { |
| return obj instanceof NullDatum; |
| } |
| |
| @Override |
| public int compareTo(Datum datum) { |
| if (datum.type() == Type.NULL_TYPE) { |
| return 0; |
| } else { |
| return 1; |
| } |
| } |
| |
| @Override |
| public Datum and(Datum datum) { |
| return BooleanDatum.AND_LOGIC[BooleanDatum.UNKNOWN_INT][datum.asInt4()]; |
| } |
| |
| @Override |
| public Datum or(Datum datum) { |
| return BooleanDatum.OR_LOGIC[BooleanDatum.UNKNOWN_INT][datum.asInt4()]; |
| } |
| |
| public NullDatum plus(Datum datum) { |
| return this; |
| } |
| |
| public NullDatum minus(Datum datum) { |
| return this; |
| } |
| |
| public NullDatum multiply(Datum datum) { |
| return this; |
| } |
| |
| public NullDatum divide(Datum datum) { |
| return this; |
| } |
| |
| public NullDatum modular(Datum datum) { |
| return this; |
| } |
| |
| public NullDatum equalsTo(Datum datum) { |
| return this; |
| } |
| |
| public NullDatum lessThan(Datum datum) { |
| return this; |
| } |
| |
| public NullDatum lessThanEqual(Datum datum) { |
| return this; |
| } |
| |
| public NullDatum greaterThan(Datum datum) { |
| return this; |
| } |
| |
| public NullDatum greaterThanEqual(Datum datum) { |
| return this; |
| } |
| |
| @Override |
| public int hashCode() { |
| return 0; |
| } |
| |
| @Override |
| public String toString() { |
| return "NULL"; |
| } |
| } |