001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *   https://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied.  See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019
020package org.apache.commons.csv;
021
022/**
023 * Determines how duplicate header fields should be handled
024 * if {@link CSVFormat.Builder#setHeader(Class)} is not null.
025 *
026 * @since 1.10.0
027 */
028public enum DuplicateHeaderMode {
029
030    /**
031     * Allows all duplicate headers.
032     */
033    ALLOW_ALL,
034
035    /**
036     * Allows duplicate headers only if they're empty, blank, or null strings.
037     */
038    ALLOW_EMPTY,
039
040    /**
041     * Disallows duplicate headers entirely.
042     */
043    DISALLOW
044}