1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.commons.fileupload2.core;
18
19 import java.util.ArrayList;
20 import java.util.Collections;
21 import java.util.Iterator;
22 import java.util.LinkedHashMap;
23 import java.util.List;
24 import java.util.Locale;
25 import java.util.Map;
26
27 /**
28 * Default implementation of the {@link FileItemHeaders} interface.
29 */
30 class FileItemHeadersImpl implements FileItemHeaders {
31
32 /**
33 * Map of {@code String} keys to a {@code List} of {@code String} instances.
34 */
35 private final Map<String, List<String>> headerNameToValueListMap = new LinkedHashMap<>();
36
37 /**
38 * Method to add header values to this instance.
39 *
40 * @param name name of this header
41 * @param value value of this header
42 */
43 @Override
44 public synchronized void addHeader(final String name, final String value) {
45 headerNameToValueListMap.computeIfAbsent(toLowerCase(name), k -> new ArrayList<>()).add(value);
46 }
47
48 /**
49 * {@inheritDoc}
50 */
51 @Override
52 public String getHeader(final String name) {
53 final var headerValueList = getList(name);
54 if (null == headerValueList) {
55 return null;
56 }
57 return headerValueList.get(0);
58 }
59
60 /**
61 * {@inheritDoc}
62 */
63 @Override
64 public Iterator<String> getHeaderNames() {
65 return headerNameToValueListMap.keySet().iterator();
66 }
67
68 /**
69 * {@inheritDoc}
70 */
71 @Override
72 public Iterator<String> getHeaders(final String name) {
73 var headerValueList = getList(name);
74 if (null == headerValueList) {
75 headerValueList = Collections.emptyList();
76 }
77 return headerValueList.iterator();
78 }
79
80 private List<String> getList(final String name) {
81 return headerNameToValueListMap.get(toLowerCase(name));
82 }
83
84 private String toLowerCase(final String value) {
85 return value.toLowerCase(Locale.ENGLISH);
86 }
87
88 }