/*
* 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 hivemall.tools;
import hivemall.utils.hadoop.HiveUtils;
import java.util.ArrayList;
import org.apache.hadoop.hive.ql.exec.Description;
import org.apache.hadoop.hive.ql.exec.UDFArgumentException;
import org.apache.hadoop.hive.ql.metadata.HiveException;
import org.apache.hadoop.hive.ql.udf.generic.GenericUDTF;
import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspector;
import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspectorFactory;
import org.apache.hadoop.hive.serde2.objectinspector.StructObjectInspector;
import org.apache.hadoop.hive.serde2.objectinspector.primitive.PrimitiveObjectInspectorFactory;
@Description(name = "generate_series",
value = "_FUNC_(const int|bigint start, const int|bigint end) - "
+ "Generate a series of values, from start to end")
public final class GenerateSeriesUDTF extends GenericUDTF {
private long start, end;
private boolean useBigInt;
@Override
public StructObjectInspector initialize(ObjectInspector[] argOIs) throws UDFArgumentException {
if (argOIs.length != 2) {
throw new UDFArgumentException("Expected number of arguments is 2: " + argOIs.length);
}
ArrayList<String> fieldNames = new ArrayList<String>(1);
fieldNames.add("value");
ArrayList<ObjectInspector> fieldOIs = new ArrayList<ObjectInspector>(1);
this.useBigInt = HiveUtils.isBigIntOI(argOIs[1]);
if (useBigInt) {
fieldOIs.add(PrimitiveObjectInspectorFactory.javaLongObjectInspector);
} else {
fieldOIs.add(PrimitiveObjectInspectorFactory.javaIntObjectInspector);
}
this.start = HiveUtils.getAsConstLong(argOIs[0]);
this.end = HiveUtils.getAsConstLong(argOIs[1]);
if (start > end) {
throw new UDFArgumentException("start '" + start
+ "' must be less than or equlas to end '" + end + "'");
}
return ObjectInspectorFactory.getStandardStructObjectInspector(fieldNames, fieldOIs);
}
@Override
public void process(Object[] argOIs) throws HiveException {
final Object[] forwardObjs = new Object[1];
if (useBigInt) {
if (start == end) {
forwardObjs[0] = start;
forward(forwardObjs);
} else {
for (long i = start; i <= end; i++) {
forwardObjs[0] = i;
forward(forwardObjs);
}
}
} else {
int starti = (int) start;
int endi = (int) end;
if (starti == endi) {
forwardObjs[0] = starti;
forward(forwardObjs);
} else {
for (int i = starti; i <= endi; i++) {
forwardObjs[0] = i;
forward(forwardObjs);
}
}
}
}
@Override
public void close() throws HiveException {}
}