org.apache.hadoop.hive.ql.udf.UDFRepeat 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 org.apache.hadoop.hive.ql.exec.Description;
import org.apache.hadoop.hive.ql.exec.UDF;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.Text;
/**
* UDFRepeat.
*
*/
@Description(name = "repeat",
value = "_FUNC_(str, n) - repeat str n times ",
extended = "Example:\n"
+ " > SELECT _FUNC_('123', 2) FROM src LIMIT 1;\n" + " '123123'")
public class UDFRepeat extends UDF {
private final Text result = new Text();
public Text evaluate(Text s, IntWritable n) {
if (n == null || s == null) {
return null;
}
int len = n.get() * s.getLength();
if (len < 0) {
len = 0;
}
byte[] data = result.getBytes();
if (data.length < len) {
data = new byte[len];
}
for (int i = 0; i < len; i += s.getLength()) {
for (int j = 0; j < s.getLength(); j++) {
data[i + j] = s.getBytes()[j];
}
}
result.set(data, 0, len);
return result;
}
}