| 1 | /* This file is part of the project "Hilbert II" - http://www.qedeq.org |
| 2 | * |
| 3 | * Copyright 2000-2014, Michael Meyling <mime@qedeq.org>. |
| 4 | * |
| 5 | * "Hilbert II" is free software; you can redistribute |
| 6 | * it and/or modify it under the terms of the GNU General Public |
| 7 | * License as published by the Free Software Foundation; either |
| 8 | * version 2 of the License, or (at your option) any later version. |
| 9 | * |
| 10 | * This program is distributed in the hope that it will be useful, |
| 11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | * GNU General Public License for more details. |
| 14 | */ |
| 15 | |
| 16 | package org.qedeq.kernel.bo.common; |
| 17 | |
| 18 | import java.util.Arrays; |
| 19 | import java.util.HashSet; |
| 20 | import java.util.Iterator; |
| 21 | import java.util.Set; |
| 22 | |
| 23 | |
| 24 | /** |
| 25 | * This class represents a set of {@link QedeqBo}s. |
| 26 | * |
| 27 | * @author Michael Meyling |
| 28 | */ |
| 29 | public class QedeqBoSet { |
| 30 | |
| 31 | |
| 32 | /** Here are the elements stored. */ |
| 33 | private final Set elements; |
| 34 | |
| 35 | |
| 36 | /** |
| 37 | * Constructs an empty element set. |
| 38 | */ |
| 39 | public QedeqBoSet() { |
| 40 | this.elements = new HashSet(); |
| 41 | } |
| 42 | |
| 43 | |
| 44 | /** |
| 45 | * Constructs an element set. |
| 46 | * |
| 47 | * @param elements the elements to put into the set |
| 48 | * @throws IllegalArgumentException if <code>elements</code> was a NullPointer |
| 49 | */ |
| 50 | public QedeqBoSet(final QedeqBo[] elements) { |
| 51 | if (elements == null) { |
| 52 | throw new IllegalArgumentException( |
| 53 | "NullPointer as element array is not allowed"); |
| 54 | } |
| 55 | this.elements = new HashSet(Arrays.asList(elements)); |
| 56 | } |
| 57 | |
| 58 | /** |
| 59 | * Constructs an element set. |
| 60 | * |
| 61 | * @param element Put this element into the set |
| 62 | * @throws IllegalArgumentException if <code>element</code> was a NullPointer |
| 63 | */ |
| 64 | public QedeqBoSet(final QedeqBo element) { |
| 65 | if (element == null) { |
| 66 | throw new IllegalArgumentException( |
| 67 | "NullPointer as element array is not allowed"); |
| 68 | } |
| 69 | this.elements = new HashSet(); |
| 70 | elements.add(element); |
| 71 | } |
| 72 | |
| 73 | /** |
| 74 | * Constructs an element set. |
| 75 | * |
| 76 | * @param set contains the elements to put into the set |
| 77 | * @throws IllegalArgumentException if <code>set</code> was a |
| 78 | * NullPointer |
| 79 | */ |
| 80 | public QedeqBoSet(final QedeqBoSet set) { |
| 81 | if (set == null) { |
| 82 | throw new IllegalArgumentException( |
| 83 | "NullPointer as set is not allowed"); |
| 84 | } |
| 85 | this.elements = new HashSet(set.elements); |
| 86 | } |
| 87 | |
| 88 | |
| 89 | /** |
| 90 | * Is element in set? |
| 91 | * |
| 92 | * @param element QedeqBo to check for. |
| 93 | * @return Is <code>element</code> in this set? |
| 94 | * @throws IllegalArgumentException if the element was a |
| 95 | * NullPointer |
| 96 | */ |
| 97 | public final boolean contains(final QedeqBo element) { |
| 98 | if (element == null) { |
| 99 | throw new IllegalArgumentException("NullPointer as element is not allowed"); |
| 100 | } |
| 101 | return this.elements.contains(element); |
| 102 | } |
| 103 | |
| 104 | /** |
| 105 | * Is this set empty? |
| 106 | * |
| 107 | * @return Is this set empty? |
| 108 | */ |
| 109 | public final boolean isEmpty() { |
| 110 | return elements.isEmpty(); |
| 111 | } |
| 112 | |
| 113 | |
| 114 | /** |
| 115 | * Add an element to set. This object is after the method the |
| 116 | * union of this set with {<code>element</code>} |
| 117 | * |
| 118 | * @param element element to put into the set |
| 119 | * @return Possibly changed <code>this</code>. |
| 120 | * @throws IllegalArgumentException if the element was a |
| 121 | * NullPointer |
| 122 | */ |
| 123 | public final QedeqBoSet add(final QedeqBo element) { |
| 124 | if (element == null) { |
| 125 | throw new IllegalArgumentException("NullPointer as element is not allowed"); |
| 126 | } |
| 127 | elements.add(element); |
| 128 | return this; |
| 129 | } |
| 130 | |
| 131 | |
| 132 | /** |
| 133 | * Add elements from another {@link QedeqBoSet} to this set. |
| 134 | * After this method this object is the union of the two sets. |
| 135 | * |
| 136 | * @param set add all elements that are here |
| 137 | * @return Possibly changed <code>this</code>. |
| 138 | * @throws IllegalArgumentException if the set was a |
| 139 | * NullPointer |
| 140 | */ |
| 141 | public final QedeqBoSet add(final QedeqBoSet set) { |
| 142 | if (set == null) { |
| 143 | throw new IllegalArgumentException( |
| 144 | "NullPointer as set is not allowed"); |
| 145 | } |
| 146 | elements.addAll(set.elements); |
| 147 | return this; |
| 148 | } |
| 149 | |
| 150 | |
| 151 | /** |
| 152 | * Remove an element from this set. |
| 153 | * |
| 154 | * @param element QedeqBo to remove from the set. Must not be <code>null</code>. |
| 155 | * @return Possibly changed <code>this</code>. |
| 156 | * @throws IllegalArgumentException if the element was a |
| 157 | * NullPointer |
| 158 | */ |
| 159 | public final QedeqBoSet remove(final QedeqBo element) { |
| 160 | if (element == null) { |
| 161 | throw new IllegalArgumentException( |
| 162 | "NullPointer as element is not allowed"); |
| 163 | } |
| 164 | elements.remove(element); |
| 165 | return this; |
| 166 | } |
| 167 | |
| 168 | /** |
| 169 | * Remove elements from another {@link QedeqBoSet} from this set. |
| 170 | * After this method this object is the asymmetric set difference of the |
| 171 | * two sets: <code>this</code> \ <code>set</code>. |
| 172 | * |
| 173 | * @param set Remove all elements that are in this set from |
| 174 | * <code>this</code>. |
| 175 | * @return Possibly changed <code>this</code>. |
| 176 | * @throws IllegalArgumentException if the set was a |
| 177 | * NullPointer |
| 178 | */ |
| 179 | public final QedeqBoSet remove(final QedeqBoSet set) { |
| 180 | if (set == null) { |
| 181 | throw new IllegalArgumentException( |
| 182 | "NullPointer as set is not allowed"); |
| 183 | } |
| 184 | this.elements.removeAll(set.elements); |
| 185 | return this; |
| 186 | } |
| 187 | |
| 188 | /** |
| 189 | * Build the intersection. |
| 190 | * |
| 191 | * @param set Check for these elements. |
| 192 | * @return Possibly changed <code>this</code>. |
| 193 | * @throws IllegalArgumentException if the set was a |
| 194 | * NullPointer |
| 195 | */ |
| 196 | public final QedeqBoSet intersection(final QedeqBoSet set) { |
| 197 | if (set == null) { |
| 198 | throw new IllegalArgumentException( |
| 199 | "NullPointer as set is not allowed"); |
| 200 | } |
| 201 | this.elements.retainAll(set.elements); |
| 202 | return this; |
| 203 | } |
| 204 | |
| 205 | |
| 206 | /** |
| 207 | * Get number of elements. |
| 208 | * |
| 209 | * @return Number of elements in this set. |
| 210 | */ |
| 211 | public final int size() { |
| 212 | return this.elements.size(); |
| 213 | } |
| 214 | |
| 215 | /** |
| 216 | * Returns an iterator over the elements in this set. The elements are |
| 217 | * returned in no particular order (unless this set is an instance of some |
| 218 | * class that provides a guarantee). |
| 219 | * |
| 220 | * @return Iterator over the elements in this set. |
| 221 | */ |
| 222 | public Iterator iterator() { |
| 223 | return this.elements.iterator(); |
| 224 | } |
| 225 | |
| 226 | public final boolean equals(final Object obj) { |
| 227 | if (obj instanceof QedeqBoSet) { |
| 228 | return this.elements.equals(((QedeqBoSet) obj).elements); |
| 229 | } |
| 230 | return false; |
| 231 | } |
| 232 | |
| 233 | public final int hashCode() { |
| 234 | return elements.hashCode(); |
| 235 | } |
| 236 | |
| 237 | public final String toString() { |
| 238 | final StringBuffer result = new StringBuffer(); |
| 239 | result.append("{"); |
| 240 | final Iterator iterator = elements.iterator(); |
| 241 | while (iterator.hasNext()) { |
| 242 | result.append(iterator.next()); |
| 243 | if (iterator.hasNext()) { |
| 244 | result.append(", "); |
| 245 | } |
| 246 | } |
| 247 | result.append("}"); |
| 248 | return result.toString(); |
| 249 | } |
| 250 | |
| 251 | |
| 252 | public String asLongList() { |
| 253 | final StringBuffer result = new StringBuffer(); |
| 254 | final Iterator iterator = elements.iterator(); |
| 255 | while (iterator.hasNext()) { |
| 256 | result.append(((QedeqBo) iterator.next()).getUrl()); |
| 257 | if (iterator.hasNext()) { |
| 258 | result.append(", "); |
| 259 | } |
| 260 | } |
| 261 | return result.toString(); |
| 262 | } |
| 263 | |
| 264 | |
| 265 | public String asShortList() { |
| 266 | final StringBuffer result = new StringBuffer(); |
| 267 | final Iterator iterator = elements.iterator(); |
| 268 | while (iterator.hasNext()) { |
| 269 | result.append(((QedeqBo) iterator.next()).getName()); |
| 270 | if (iterator.hasNext()) { |
| 271 | result.append(", "); |
| 272 | } |
| 273 | } |
| 274 | return result.toString(); |
| 275 | } |
| 276 | |
| 277 | |
| 278 | } |