/*
* 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.piggybank.evaluation.datetime.convert;
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.DateTimeZone;
import org.joda.time.format.DateTimeFormat;
import org.joda.time.format.DateTimeFormatter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
/**
* CustomFormatToISO converts arbitrary date formats to ISO format.
* <ul>
* <li>Jodatime: http://joda-time.sourceforge.net/</li>
* <li>ISO8601 Date Format: http://en.wikipedia.org/wiki/ISO_8601</li>
* <li>Jodatime custom date formats: http://joda-time.sourceforge.net/api-release/org/joda/time/format/DateTimeFormat.html</li>
* </ul>
* <br />
* <pre>
* Example usage:
*
* REGISTER /Users/me/commiter/piggybank/java/piggybank.jar ;
* REGISTER /Users/me/commiter/piggybank/java/lib/joda-time-1.6.jar ;
*
* DEFINE CustomFormatToISO org.apache.pig.piggybank.evaluation.datetime.convert.CustomFormatToISO();
* CustomIn = LOAD 'test3.tsv' USING PigStorage('\t') AS (dt:chararray);
*
* DESCRIBE CustomIn;
* CustomIn: {dt: chararray}
*
* DUMP CustomIn;
*
* (10-1-2010)
*
* toISO = FOREACH CustomIn GENERATE CustomFormatToISO(dt, "MM-dd-YYYY") AS ISOTime:chararray;
*
* DESCRIBE toISO;
* toISO: {ISOTime: chararray}
*
* DUMP toISO;
* (2010-10-01T00:00:00.000Z)
* ...
* </pre>
*/
public class CustomFormatToISO extends EvalFunc<String> {
@Override
public String exec(Tuple input) throws IOException
{
if (input == null || input.size() < 2) {
return null;
}
// Set the time to default or the output is in UTC
DateTimeZone.setDefault(DateTimeZone.UTC);
String date = input.get(0).toString();
String format = input.get(1).toString();
// See http://joda-time.sourceforge.net/api-release/org/joda/time/format/DateTimeFormat.html
DateTimeFormatter parser = DateTimeFormat.forPattern(format);
DateTime result;
try {
result = parser.parseDateTime(date);
} catch(Exception e) {
return null;
}
return result.toString();
}
@Override
public Schema outputSchema(Schema input) {
return new Schema(new Schema.FieldSchema(getSchemaName(this.getClass().getName().toLowerCase(), input), DataType.CHARARRAY));
}
@Override
public List<FuncSpec> getArgToFuncMapping() throws FrontendException {
List<FuncSpec> funcList = new ArrayList<FuncSpec>();
Schema s = new Schema();
s.add(new Schema.FieldSchema(null, DataType.CHARARRAY));
s.add(new Schema.FieldSchema(null, DataType.CHARARRAY));
funcList.add(new FuncSpec(this.getClass().getName(), s));
return funcList;
}
}