/*
* 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.pig.builtin;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import org.apache.pig.EvalFunc;
import org.apache.pig.FuncSpec;
import org.apache.pig.data.DataType;
import org.apache.pig.data.Tuple;
import org.apache.pig.impl.logicalLayer.FrontendException;
import org.apache.pig.impl.logicalLayer.schema.Schema;
import org.joda.time.DateTime;
import org.joda.time.Years;
/**
* <p>YearsBetween returns the number of years between two DateTime objects</p>
*
* <ul>
* <li>Jodatime: http://joda-time.sourceforge.net/</li>
* <li>ISO8601 Date Format: http://en.wikipedia.org/wiki/ISO_8601</li>
* </ul>
* <br />
* <pre>
* Example usage:
*
* ISOin = LOAD 'test.tsv' USING PigStorage('\t') AS (datetime, dt2:datetime);
*
* DESCRIBE ISOin;
* ISOin: {dt: datetime,dt2: datetime}
*
* DUMP ISOin;
*
* (2009-01-07T01:07:01.000Z,2008-02-01T00:00:00.000Z)
* (2008-02-06T02:06:02.000Z,2008-02-01T00:00:00.000Z)
* (2007-03-05T03:05:03.000Z,2008-02-01T00:00:00.000Z)
* ...
*
* diffs = FOREACH ISOin GENERATE YearsBetween(dt, dt2) AS years,
* MonthsBetween(dt, dt2) AS months,
* WeeksBetween(dt, dt2) AS weeks,
* DaysBetween(dt, dt2) AS days,
* HoursBetween(dt, dt2) AS hours,
* MinutesBetween(dt, dt2) AS mins,
* SecondsBetween(dt, dt2) AS secs;
* MilliSecondsBetween(dt, dt2) AS millis;
*
* DESCRIBE diffs;
* diffs: {years: long,months: long,weeks: long,days: long,hours: long,mins: long,secs: long,millis: long}
*
* DUMP diffs;
*
* (0L,11L,48L,341L,8185L,491107L,29466421L,29466421000L)
* (0L,0L,0L,5L,122L,7326L,439562L,439562000L)
* (0L,-10L,-47L,-332L,-7988L,-479334L,-28760097L,-28760097000L)
*
* </pre>
*/
public class YearsBetween extends EvalFunc<Long> {
@Override
public Long exec(Tuple input) throws IOException
{
if (input == null || input.size() < 2) {
return null;
}
DateTime startDate = (DateTime) input.get(0);
DateTime endDate = (DateTime) input.get(1);
// Larger value first
Years y = Years.yearsBetween(endDate, startDate);
// joda limitation, only integer range, at the risk of overflow, need to be improved
return (long) y.getYears();
}
@Override
public Schema outputSchema(Schema input) {
return new Schema(new Schema.FieldSchema(getSchemaName(this.getClass().getName().toLowerCase(), input), DataType.LONG));
}
@Override
public List<FuncSpec> getArgToFuncMapping() throws FrontendException {
List<FuncSpec> funcList = new ArrayList<FuncSpec>();
Schema s = new Schema();
s.add(new Schema.FieldSchema(null, DataType.DATETIME));
s.add(new Schema.FieldSchema(null, DataType.DATETIME));
funcList.add(new FuncSpec(this.getClass().getName(), s));
return funcList;
}
}