/**
* 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 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.vector.VectorizedExpressions;
import org.apache.hadoop.hive.ql.exec.vector.expressions.VectorUDFDateLong;
import org.apache.hadoop.hive.ql.exec.vector.expressions.VectorUDFDateString;
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.ObjectInspector.Category;
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.PrimitiveObjectInspectorConverter.TimestampConverter;
import org.apache.hadoop.hive.serde2.objectinspector.primitive.PrimitiveObjectInspectorFactory;
import org.apache.hadoop.io.Text;
/**
* UDFDate.
*
*/
@Description(name = "to_date",
value = "_FUNC_(expr) - Extracts the date part of the date or datetime expression expr",
extended = "Example:\n "
+ " > SELECT _FUNC_('2009-07-30 04:17:52') FROM src LIMIT 1;\n"
+ " '2009-07-30'")
@VectorizedExpressions({VectorUDFDateString.class, VectorUDFDateLong.class})
public class GenericUDFDate extends GenericUDF {
private transient SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
private transient TimestampConverter timestampConverter;
private transient Converter textConverter;
private transient Converter dateWritableConverter;
private transient PrimitiveCategory inputType;
private transient PrimitiveObjectInspector argumentOI;
private final Text output = new Text();
@Override
public ObjectInspector initialize(ObjectInspector[] arguments) throws UDFArgumentException {
if (arguments.length != 1) {
throw new UDFArgumentLengthException(
"to_date() requires 1 argument, got " + arguments.length);
}
if (arguments[0].getCategory() != Category.PRIMITIVE) {
throw new UDFArgumentException("to_date() only accepts STRING/TIMESTAMP/DATEWRITABLE types, got "
+ arguments[0].getTypeName());
}
argumentOI = (PrimitiveObjectInspector) arguments[0];
inputType = argumentOI.getPrimitiveCategory();
ObjectInspector outputOI = PrimitiveObjectInspectorFactory.writableStringObjectInspector;
switch (inputType) {
case CHAR:
case VARCHAR:
case STRING:
inputType = PrimitiveCategory.STRING;
textConverter = ObjectInspectorConverters.getConverter(
argumentOI, PrimitiveObjectInspectorFactory.writableStringObjectInspector);
break;
case TIMESTAMP:
timestampConverter = new TimestampConverter(argumentOI,
PrimitiveObjectInspectorFactory.writableTimestampObjectInspector);
break;
case DATE:
dateWritableConverter = ObjectInspectorConverters.getConverter(argumentOI,
PrimitiveObjectInspectorFactory.writableDateObjectInspector);
break;
default:
throw new UDFArgumentException(
"TO_DATE() only takes STRING/TIMESTAMP/DATEWRITABLE types, got " + inputType);
}
return outputOI;
}
@Override
public Object evaluate(DeferredObject[] arguments) throws HiveException {
if (arguments[0].get() == null) {
return null;
}
switch (inputType) {
case STRING:
Date date;
String dateString = textConverter.convert(arguments[0].get()).toString();
try {
date = formatter.parse(dateString);
} catch (ParseException e) {
return null;
}
output.set(formatter.format(date));
break;
case TIMESTAMP:
Timestamp ts = ((TimestampWritable) timestampConverter.convert(arguments[0].get()))
.getTimestamp();
output.set(formatter.format(ts));
break;
case DATE:
DateWritable dw = (DateWritable) dateWritableConverter.convert(arguments[0].get());
output.set(formatter.format(dw.get()));
break;
default:
throw new UDFArgumentException(
"TO_DATE() only takes STRING/TIMESTAMP/DATEWRITABLE types, got " + inputType);
}
return output;
}
@Override
public String getDisplayString(String[] children) {
StringBuilder sb = new StringBuilder();
sb.append("to_date(");
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();
}
}