org.apache.hadoop.hive.ql.udf.UDFDayOfWeek Maven / Gradle / Ivy
/**
* 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.hadoop.hive.ql.udf;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import org.apache.hadoop.hive.ql.exec.Description;
import org.apache.hadoop.hive.ql.exec.UDF;
import org.apache.hadoop.hive.ql.exec.vector.VectorizedExpressions;
import org.apache.hadoop.hive.ql.exec.vector.expressions.VectorUDFDayOfWeekDate;
import org.apache.hadoop.hive.ql.exec.vector.expressions.VectorUDFDayOfWeekString;
import org.apache.hadoop.hive.ql.exec.vector.expressions.VectorUDFDayOfWeekTimestamp;
import org.apache.hadoop.hive.ql.udf.generic.NDV;
import org.apache.hadoop.hive.serde2.io.DateWritable;
import org.apache.hadoop.hive.serde2.io.TimestampWritable;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.Text;
/**
* UDFDayOfWeek.
*
*/
@Description(name = "dayofweek",
value = "_FUNC_(param) - Returns the day of the week of date/timestamp "
+ "(1 = Sunday, 2 = Monday, ..., 7 = Saturday)",
extended = "param can be one of:\n"
+ "1. A string in the format of 'yyyy-MM-dd HH:mm:ss' or 'yyyy-MM-dd'.\n"
+ "2. A date value\n"
+ "3. A timestamp value"
+ "Example:\n "
+ " > SELECT _FUNC_('2009-07-30') FROM src LIMIT 1;\n" + " 5")
@VectorizedExpressions({VectorUDFDayOfWeekDate.class, VectorUDFDayOfWeekString.class, VectorUDFDayOfWeekTimestamp.class})
@NDV(maxNdv = 7)
public class UDFDayOfWeek extends UDF {
private final SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
private final Calendar calendar = Calendar.getInstance();
private final IntWritable result = new IntWritable();
public UDFDayOfWeek() {
}
/**
* Get the day of week from a date string.
*
* @param dateString
* the dateString in the format of "yyyy-MM-dd HH:mm:ss" or
* "yyyy-MM-dd".
* @return an int from 1 to 7. null if the dateString is not a valid date
* string.
*/
public IntWritable evaluate(Text dateString) {
if (dateString == null) {
return null;
}
try {
Date date = formatter.parse(dateString.toString());
calendar.setTime(date);
result.set(calendar.get(Calendar.DAY_OF_WEEK));
return result;
} catch (ParseException e) {
return null;
}
}
public IntWritable evaluate(DateWritable d) {
if (d == null) {
return null;
}
calendar.setTime(d.get(false)); // Time doesn't matter.
result.set(calendar.get(Calendar.DAY_OF_WEEK));
return result;
}
public IntWritable evaluate(TimestampWritable t) {
if (t == null) {
return null;
}
calendar.setTime(t.getTimestamp());
result.set(calendar.get(Calendar.DAY_OF_WEEK));
return result;
}
}