Java tutorial
/* * 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.phoenix.expression.function; import java.util.List; import org.apache.hadoop.hbase.io.ImmutableBytesWritable; import org.apache.phoenix.expression.Expression; import org.apache.phoenix.parse.FunctionParseNode.Argument; import org.apache.phoenix.parse.FunctionParseNode.BuiltInFunction; import org.apache.phoenix.schema.tuple.Tuple; import org.apache.phoenix.schema.types.PDataType; import org.apache.phoenix.schema.types.PInteger; import org.apache.phoenix.schema.types.PTimestamp; import org.joda.time.DateTime; /** * Implementation of DayOfWeekFunction(Date/Timestamp) * * Returns an integer from 1 to 7. Each represents a day of the week as follows : * MONDAY = 1; * TUESDAY = 2; * WEDNESDAY = 3; * THURSDAY = 4; * FRIDAY = 5; * SATURDAY = 6; * SUNDAY = 7; * */ @BuiltInFunction(name = DayOfWeekFunction.NAME, args = { @Argument(allowedTypes = { PTimestamp.class }) }) public class DayOfWeekFunction extends DateScalarFunction { public static final String NAME = "DAYOFWEEK"; public DayOfWeekFunction() { } public DayOfWeekFunction(List<Expression> children) { super(children); } @Override public String getName() { return NAME; } @Override public boolean evaluate(Tuple tuple, ImmutableBytesWritable ptr) { Expression arg = getChildren().get(0); if (!arg.evaluate(tuple, ptr)) { return false; } if (ptr.getLength() == 0) { return true; } long dateTime = inputCodec.decodeLong(ptr, arg.getSortOrder()); DateTime jodaDT = new DateTime(dateTime); int day = jodaDT.getDayOfWeek(); PDataType returnDataType = getDataType(); byte[] byteValue = new byte[returnDataType.getByteSize()]; returnDataType.getCodec().encodeInt(day, byteValue, 0); ptr.set(byteValue); return true; } @Override public PDataType getDataType() { return PInteger.INSTANCE; } }