1 /*
2 * ====================================================================
3 * Licensed to the Apache Software Foundation (ASF) under one
4 * or more contributor license agreements. See the NOTICE file
5 * distributed with this work for additional information
6 * regarding copyright ownership. The ASF licenses this file
7 * to you under the Apache License, Version 2.0 (the
8 * "License"); you may not use this file except in compliance
9 * with the License. You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing,
14 * software distributed under the License is distributed on an
15 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
16 * KIND, either express or implied. See the License for the
17 * specific language governing permissions and limitations
18 * under the License.
19 * ====================================================================
20 *
21 * This software consists of voluntary contributions made by many
22 * individuals on behalf of the Apache Software Foundation. For more
23 * information on the Apache Software Foundation, please see
24 * <http://www.apache.org/>.
25 *
26 */
27
28 package org.apache.http.impl.client;
29
30 import java.net.URI;
31 import java.util.AbstractList;
32 import java.util.ArrayList;
33 import java.util.HashSet;
34 import java.util.Iterator;
35 import java.util.List;
36 import java.util.Set;
37
38 /**
39 * This class represents a collection of {@link java.net.URI}s used
40 * as redirect locations.
41 *
42 * @since 4.0
43 */
44 public class RedirectLocations extends AbstractList<Object> {
45
46 private final Set<URI> unique;
47 private final List<URI> all;
48
49 public RedirectLocations() {
50 super();
51 this.unique = new HashSet<URI>();
52 this.all = new ArrayList<URI>();
53 }
54
55 /**
56 * Test if the URI is present in the collection.
57 */
58 public boolean contains(final URI uri) {
59 return this.unique.contains(uri);
60 }
61
62 /**
63 * Adds a new URI to the collection.
64 */
65 public void add(final URI uri) {
66 this.unique.add(uri);
67 this.all.add(uri);
68 }
69
70 /**
71 * Removes a URI from the collection.
72 */
73 public boolean remove(final URI uri) {
74 final boolean removed = this.unique.remove(uri);
75 if (removed) {
76 final Iterator<URI> it = this.all.iterator();
77 while (it.hasNext()) {
78 final URI current = it.next();
79 if (current.equals(uri)) {
80 it.remove();
81 }
82 }
83 }
84 return removed;
85 }
86
87 /**
88 * Returns all redirect {@link URI}s in the order they were added to the collection.
89 *
90 * @return list of all URIs
91 *
92 * @since 4.1
93 */
94 public List<URI> getAll() {
95 return new ArrayList<URI>(this.all);
96 }
97
98 /**
99 * Returns the URI at the specified position in this list.
100 *
101 * @param index
102 * index of the location to return
103 * @return the URI at the specified position in this list
104 * @throws IndexOutOfBoundsException
105 * if the index is out of range (
106 * {@code index < 0 || index >= size()})
107 * @since 4.3
108 */
109 @Override
110 public URI get(final int index) {
111 return this.all.get(index);
112 }
113
114 /**
115 * Returns the number of elements in this list. If this list contains more
116 * than {@code Integer.MAX_VALUE} elements, returns
117 * {@code Integer.MAX_VALUE}.
118 *
119 * @return the number of elements in this list
120 * @since 4.3
121 */
122 @Override
123 public int size() {
124 return this.all.size();
125 }
126
127 /**
128 * Replaces the URI at the specified position in this list with the
129 * specified element (must be a URI).
130 *
131 * @param index
132 * index of the element to replace
133 * @param element
134 * URI to be stored at the specified position
135 * @return the URI previously at the specified position
136 * @throws UnsupportedOperationException
137 * if the {@code set} operation is not supported by this list
138 * @throws ClassCastException
139 * if the element is not a {@link URI}
140 * @throws NullPointerException
141 * if the specified element is null and this list does not
142 * permit null elements
143 * @throws IndexOutOfBoundsException
144 * if the index is out of range (
145 * {@code index < 0 || index >= size()})
146 * @since 4.3
147 */
148 @Override
149 public Object set(final int index, final Object element) {
150 final URI removed = this.all.set(index, (URI) element);
151 this.unique.remove(removed);
152 this.unique.add((URI) element);
153 if (this.all.size() != this.unique.size()) {
154 this.unique.addAll(this.all);
155 }
156 return removed;
157 }
158
159 /**
160 * Inserts the specified element at the specified position in this list
161 * (must be a URI). Shifts the URI currently at that position (if any) and
162 * any subsequent URIs to the right (adds one to their indices).
163 *
164 * @param index
165 * index at which the specified element is to be inserted
166 * @param element
167 * URI to be inserted
168 * @throws UnsupportedOperationException
169 * if the {@code add} operation is not supported by this list
170 * @throws ClassCastException
171 * if the element is not a {@link URI}
172 * @throws NullPointerException
173 * if the specified element is null and this list does not
174 * permit null elements
175 * @throws IndexOutOfBoundsException
176 * if the index is out of range (
177 * {@code index < 0 || index > size()})
178 * @since 4.3
179 */
180 @Override
181 public void add(final int index, final Object element) {
182 this.all.add(index, (URI) element);
183 this.unique.add((URI) element);
184 }
185
186 /**
187 * Removes the URI at the specified position in this list. Shifts any
188 * subsequent URIs to the left (subtracts one from their indices). Returns
189 * the URI that was removed from the list.
190 *
191 * @param index
192 * the index of the URI to be removed
193 * @return the URI previously at the specified position
194 * @throws IndexOutOfBoundsException
195 * if the index is out of range (
196 * {@code index < 0 || index >= size()})
197 * @since 4.3
198 */
199 @Override
200 public URI remove(final int index) {
201 final URI removed = this.all.remove(index);
202 this.unique.remove(removed);
203 if (this.all.size() != this.unique.size()) {
204 this.unique.addAll(this.all);
205 }
206 return removed;
207 }
208
209 /**
210 * Returns {@code true} if this collection contains the specified element.
211 * More formally, returns {@code true} if and only if this collection
212 * contains at least one element {@code e} such that
213 * {@code (o==null ? e==null : o.equals(e))}.
214 *
215 * @param o element whose presence in this collection is to be tested
216 * @return {@code true} if this collection contains the specified
217 * element
218 */
219 @Override
220 public boolean contains(final Object o) {
221 return this.unique.contains(o);
222 }
223
224 }