/**
* 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.generic;
import java.sql.Timestamp;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.TimeZone;
import org.apache.hadoop.hive.ql.exec.Description;
import org.apache.hadoop.hive.ql.exec.UDFArgumentException;
import org.apache.hadoop.hive.ql.exec.UDFArgumentLengthException;
import org.apache.hadoop.hive.ql.exec.UDFArgumentTypeException;
import org.apache.hadoop.hive.ql.exec.vector.VectorizedExpressions;
import org.apache.hadoop.hive.ql.exec.vector.expressions.VectorUDFDateDiffColCol;
import org.apache.hadoop.hive.ql.exec.vector.expressions.VectorUDFDateDiffColScalar;
import org.apache.hadoop.hive.ql.exec.vector.expressions.VectorUDFDateDiffScalarCol;
import org.apache.hadoop.hive.ql.metadata.HiveException;
import org.apache.hadoop.hive.serde2.io.DateWritable;
import org.apache.hadoop.hive.serde2.io.TimestampWritable;
import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspector;
import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspectorConverters;
import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspectorConverters.Converter;
import org.apache.hadoop.hive.serde2.objectinspector.PrimitiveObjectInspector;
import org.apache.hadoop.hive.serde2.objectinspector.PrimitiveObjectInspector.PrimitiveCategory;
import org.apache.hadoop.hive.serde2.objectinspector.primitive.PrimitiveObjectInspectorFactory;
import org.apache.hadoop.hive.serde2.objectinspector.primitive.PrimitiveObjectInspectorConverter.TimestampConverter;
import org.apache.hadoop.io.IntWritable;
/**
* UDFDateDiff.
*
* Calculate the difference in the number of days. The time part of the string
* will be ignored. If dateString1 is earlier than dateString2, then the
* result can be negative.
*
*/
@Description(name = "datediff",
value = "_FUNC_(date1, date2) - Returns the number of days between date1 and date2",
extended = "date1 and date2 are strings in the format "
+ "'yyyy-MM-dd HH:mm:ss' or 'yyyy-MM-dd'. The time parts are ignored."
+ "If date1 is earlier than date2, the result is negative.\n"
+ "Example:\n "
+ " > SELECT _FUNC_('2009-30-07', '2009-31-07') FROM src LIMIT 1;\n"
+ " 1")
@VectorizedExpressions({VectorUDFDateDiffColScalar.class, VectorUDFDateDiffColCol.class, VectorUDFDateDiffScalarCol.class})
public class GenericUDFDateDiff extends GenericUDF {
private transient SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
private transient Converter inputConverter1;
private transient Converter inputConverter2;
private IntWritable output = new IntWritable();
private transient PrimitiveCategory inputType1;
private transient PrimitiveCategory inputType2;
private IntWritable result = new IntWritable();
public GenericUDFDateDiff() {
formatter.setTimeZone(TimeZone.getTimeZone("UTC"));
}
@Override
public ObjectInspector initialize(ObjectInspector[] arguments) throws UDFArgumentException {
if (arguments.length != 2) {
throw new UDFArgumentLengthException(
"datediff() requires 2 argument, got " + arguments.length);
}
inputConverter1 = checkArguments(arguments, 0);
inputConverter2 = checkArguments(arguments, 1);
inputType1 = ((PrimitiveObjectInspector) arguments[0]).getPrimitiveCategory();
inputType2 = ((PrimitiveObjectInspector) arguments[1]).getPrimitiveCategory();
ObjectInspector outputOI = PrimitiveObjectInspectorFactory.writableIntObjectInspector;
return outputOI;
}
@Override
public IntWritable evaluate(DeferredObject[] arguments) throws HiveException {
output = evaluate(convertToDate(inputType1, inputConverter1, arguments[0]),
convertToDate(inputType2, inputConverter2, arguments[1]));
return output;
}
@Override
public String getDisplayString(String[] children) {
StringBuilder sb = new StringBuilder();
sb.append("datediff(");
if (children.length > 0) {
sb.append(children[0]);
for (int i = 1; i < children.length; i++) {
sb.append(", ");
sb.append(children[i]);
}
}
sb.append(")");
return sb.toString();
}
private Date convertToDate(PrimitiveCategory inputType, Converter converter, DeferredObject argument)
throws HiveException {
assert(converter != null);
assert(argument != null);
if (argument.get() == null) {
return null;
}
Date date = new Date();
switch (inputType) {
case STRING:
case VARCHAR:
case CHAR:
String dateString = converter.convert(argument.get()).toString();
try {
date = formatter.parse(dateString);
} catch (ParseException e) {
return null;
}
break;
case TIMESTAMP:
Timestamp ts = ((TimestampWritable) converter.convert(argument.get()))
.getTimestamp();
date.setTime(ts.getTime());
break;
case DATE:
DateWritable dw = (DateWritable) converter.convert(argument.get());
date = dw.get();
break;
default:
throw new UDFArgumentException(
"TO_DATE() only takes STRING/TIMESTAMP/DATEWRITABLE types, got " + inputType);
}
return date;
}
private Converter checkArguments(ObjectInspector[] arguments, int i) throws UDFArgumentException {
if (arguments[i].getCategory() != ObjectInspector.Category.PRIMITIVE) {
throw new UDFArgumentTypeException(0,
"Only primitive type arguments are accepted but "
+ arguments[i].getTypeName() + " is passed. as first arguments");
}
PrimitiveCategory inputType = ((PrimitiveObjectInspector) arguments[i]).getPrimitiveCategory();
Converter converter;
switch (inputType) {
case STRING:
case VARCHAR:
case CHAR:
converter = ObjectInspectorConverters.getConverter(
(PrimitiveObjectInspector) arguments[i],
PrimitiveObjectInspectorFactory.writableStringObjectInspector);
break;
case TIMESTAMP:
converter = new TimestampConverter((PrimitiveObjectInspector) arguments[i],
PrimitiveObjectInspectorFactory.writableTimestampObjectInspector);
break;
case DATE:
converter = ObjectInspectorConverters.getConverter((PrimitiveObjectInspector)arguments[i],
PrimitiveObjectInspectorFactory.writableDateObjectInspector);
break;
default:
throw new UDFArgumentException(
" DATEDIFF() only takes STRING/TIMESTAMP/DATEWRITABLE types as " + (i + 1)
+ "-th argument, got " + inputType);
}
return converter;
}
private IntWritable evaluate(Date date, Date date2) {
if (date == null || date2 == null) {
return null;
}
// NOTE: This implementation avoids the extra-second problem
// by comparing with UTC epoch and integer division.
// 86400 is the number of seconds in a day
long diffInMilliSeconds = date.getTime() - date2.getTime();
result.set((int) (diffInMilliSeconds / (86400 * 1000)));
return result;
}
}