org.apache.hadoop.hive.ql.udf.UDFToFloat Maven / Gradle / Ivy
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* 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 org.apache.hadoop.hive.common.type.TimestampTZUtil;
import org.apache.hadoop.hive.ql.exec.Description;
import org.apache.hadoop.hive.ql.exec.UDF;
import org.apache.hadoop.hive.ql.exec.UDFMethodResolver;
import org.apache.hadoop.hive.ql.exec.vector.VectorizedExpressions;
import org.apache.hadoop.hive.ql.exec.vector.expressions.CastDecimalToFloat;
import org.apache.hadoop.hive.ql.exec.vector.expressions.CastStringToFloat;
import org.apache.hadoop.hive.ql.exec.vector.expressions.gen.CastLongToFloatViaLongToDouble;
import org.apache.hadoop.hive.ql.exec.vector.expressions.CastTimestampToDouble;
import org.apache.hadoop.hive.serde2.io.ByteWritable;
import org.apache.hadoop.hive.serde2.io.DoubleWritable;
import org.apache.hadoop.hive.serde2.io.HiveDecimalWritable;
import org.apache.hadoop.hive.serde2.io.ShortWritable;
import org.apache.hadoop.hive.serde2.io.TimestampWritableV2;
import org.apache.hadoop.hive.serde2.lazy.LazyUtils;
import org.apache.hadoop.io.BooleanWritable;
import org.apache.hadoop.io.FloatWritable;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.io.Text;
/**
* UDFToFloat.
*
*/
@VectorizedExpressions({CastTimestampToDouble.class, CastLongToFloatViaLongToDouble.class,
CastDecimalToFloat.class, CastStringToFloat.class})
@Description(
name = "float",
value = "_FUNC_(x) - converts it's parameter to _FUNC_",
extended =
"- x is NULL -> NULL\n" +
"- byte, short, integer, long, float, double, decimal, timestamp:\n" +
" x fits into the type _FUNC_ -> x\n" +
" undefined otherwise\n" +
"- boolean:\n" +
" true -> 1.0\n" +
" false -> 0.0\n" +
"- string:\n" +
" x is a valid _FUNC_ -> x\n" +
" NULL otherwise\n" +
"Example:\n "
+ " > SELECT _FUNC_(true);\n"
+ " 1.0")
public class UDFToFloat extends UDF {
private final FloatWritable floatWritable = new FloatWritable();
public UDFToFloat() {
}
@Override
public UDFMethodResolver getResolver() {
return new TimestampCastRestrictorResolver(super.getResolver());
}
/**
* Convert from void to a float. This is called for CAST(... AS FLOAT)
*
* @param i
* The void value to convert
* @return FloatWritable
*/
public FloatWritable evaluate(NullWritable i) {
return null;
}
/**
* Convert from boolean to a float. This is called for CAST(... AS FLOAT)
*
* @param i
* The boolean value to convert
* @return FloatWritable
*/
public FloatWritable evaluate(BooleanWritable i) {
if (i == null) {
return null;
} else {
floatWritable.set(i.get() ? (float) 1.0 : (float) 0.0);
return floatWritable;
}
}
/**
* Convert from byte to a float. This is called for CAST(... AS FLOAT)
*
* @param i
* The byte value to convert
* @return FloatWritable
*/
public FloatWritable evaluate(ByteWritable i) {
if (i == null) {
return null;
} else {
floatWritable.set(i.get());
return floatWritable;
}
}
/**
* Convert from short to a float. This is called for CAST(... AS FLOAT)
*
* @param i
* The short value to convert
* @return FloatWritable
*/
public FloatWritable evaluate(ShortWritable i) {
if (i == null) {
return null;
} else {
floatWritable.set(i.get());
return floatWritable;
}
}
/**
* Convert from integer to a float. This is called for CAST(... AS FLOAT)
*
* @param i
* The integer value to convert
* @return FloatWritable
*/
public FloatWritable evaluate(IntWritable i) {
if (i == null) {
return null;
} else {
floatWritable.set(i.get());
return floatWritable;
}
}
/**
* Convert from long to a float. This is called for CAST(... AS FLOAT)
*
* @param i
* The long value to convert
* @return FloatWritable
*/
public FloatWritable evaluate(LongWritable i) {
if (i == null) {
return null;
} else {
floatWritable.set(i.get());
return floatWritable;
}
}
/**
* Convert from double to a float. This is called for CAST(... AS FLOAT)
*
* @param i
* The double value to convert
* @return FloatWritable
*/
public FloatWritable evaluate(DoubleWritable i) {
if (i == null) {
return null;
} else {
floatWritable.set((float) i.get());
return floatWritable;
}
}
/**
* Convert from string to a float. This is called for CAST(... AS FLOAT)
*
* @param i
* The string value to convert
* @return FloatWritable
*/
public FloatWritable evaluate(Text i) {
if (i == null) {
return null;
} else {
if (!LazyUtils.isNumberMaybe(i.getBytes(), 0, i.getLength())) {
return null;
}
try {
floatWritable.set(Float.parseFloat(i.toString()));
return floatWritable;
} catch (NumberFormatException e) {
// MySQL returns 0 if the string is not a well-formed numeric value.
// But we decided to return NULL instead, which is more conservative.
return null;
}
}
}
public FloatWritable evaluate(TimestampWritableV2 i) {
if (i == null) {
return null;
} else {
try {
floatWritable.set((float) TimestampTZUtil.convertTimestampTZToDouble(
UDFUtils.getTimestampTZFromTimestamp(i.getTimestamp())
));
return floatWritable;
} catch (NumberFormatException e) {
// MySQL returns 0 if the string is not a well-formed numeric value.
// But we decided to return NULL instead, which is more conservative.
return null;
}
}
}
public FloatWritable evaluate(HiveDecimalWritable i) {
if (i == null || !i.isSet()) {
return null;
} else {
floatWritable.set(i.floatValue());
return floatWritable;
}
}
}