/*
 * 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.spark.sql.hive.execution;

import java.util.List;

import org.apache.commons.lang3.StringUtils;
import org.apache.hadoop.hive.ql.exec.UDF;

public class UDFListString extends UDF {

  public String evaluate(Object a) {
    if (a == null) {
      return null;
    }
    @SuppressWarnings("unchecked")
    List<Object> s = (List<Object>) a;

    return StringUtils.join(s, ',');
  }


}
