/**
* 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 org.apache.hadoop.hive.ql.exec.Description;
import org.apache.hadoop.hive.ql.exec.UDFArgumentTypeException;
import org.apache.hadoop.hive.ql.parse.SemanticException;
import org.apache.hadoop.hive.ql.udf.generic.GenericUDAFMkCollectionEvaluator.BufferType;
import org.apache.hadoop.hive.serde2.typeinfo.TypeInfo;
@Description(name = "collect_list", value = "_FUNC_(x) - Returns a list of objects with duplicates")
public class GenericUDAFCollectList extends AbstractGenericUDAFResolver {
public GenericUDAFCollectList() {
}
@Override
public GenericUDAFEvaluator getEvaluator(TypeInfo[] parameters)
throws SemanticException {
if (parameters.length != 1) {
throw new UDFArgumentTypeException(parameters.length - 1,
"Exactly one argument is expected.");
}
switch (parameters[0].getCategory()) {
case PRIMITIVE:
case STRUCT:
case MAP:
case LIST:
break;
default:
throw new UDFArgumentTypeException(0,
"Only primitive, struct, list or map type arguments are accepted but "
+ parameters[0].getTypeName() + " was passed as parameter 1.");
}
return new GenericUDAFMkCollectionEvaluator(BufferType.LIST);
}
}