1 /* 2 * Hunt - A refined core library for D programming language. 3 * 4 * Copyright (C) 2018-2019 HuntLabs 5 * 6 * Website: https://www.huntlabs.net/ 7 * 8 * Licensed under the Apache-2.0 License. 9 * 10 */ 11 12 module hunt.collection.Collection; 13 14 import hunt.Functions; 15 import hunt.Object; 16 import hunt.util.Common; 17 import std.range; 18 19 interface Collection(E) : Iterable!E, IObject { 20 // Query Operations 21 22 /** 23 * Returns the number of elements in this collection. If this collection 24 * contains more than <tt>Integer.MAX_VALUE</tt> elements, returns 25 * <tt>Integer.MAX_VALUE</tt>. 26 * 27 * @return the number of elements in this collection 28 */ 29 int size(); 30 31 /** 32 * Returns <tt>true</tt> if this collection contains no elements. 33 * 34 * @return <tt>true</tt> if this collection contains no elements 35 */ 36 bool isEmpty(); 37 38 /** 39 * Returns <tt>true</tt> if this collection contains the specified element. 40 * More formally, returns <tt>true</tt> if and only if this collection 41 * contains at least one element <tt>e</tt> such that 42 * <tt>(o==null ? e==null : o.equals(e))</tt>. 43 * 44 * @param o element whose presence in this collection is to be tested 45 * @return <tt>true</tt> if this collection contains the specified 46 * element 47 * @throws ClassCastException if the type of the specified element 48 * is incompatible with this collection 49 * (<a href="#optional-restrictions">optional</a>) 50 * @throws NullPointerException if the specified element is null and this 51 * collection does not permit null elements 52 * (<a href="#optional-restrictions">optional</a>) 53 */ 54 bool contains(E o); 55 56 /** 57 * Returns an iterator over the elements in this collection. There are no 58 * guarantees concerning the order in which the elements are returned 59 * (unless this collection is an instance of some class that provides a 60 * guarantee). 61 * 62 * @return an <tt>Iterator</tt> over the elements in this collection 63 */ 64 InputRange!E iterator(); 65 66 /** 67 * Returns an array containing all of the elements in this collection. 68 * If this collection makes any guarantees as to what order its elements 69 * are returned by its iterator, this method must return the elements in 70 * the same order. 71 * 72 * <p>The returned array will be "safe" in that no references to it are 73 * maintained by this collection. (In other words, this method must 74 * allocate a new array even if this collection is backed by an array). 75 * The caller is thus free to modify the returned array. 76 * 77 * <p>This method acts as bridge between array-based and collection-based 78 * APIs. 79 * 80 * @return an array containing all of the elements in this collection 81 */ 82 E[] toArray(); 83 84 /** 85 * Returns an array containing all of the elements in this collection; 86 * the runtime type of the returned array is that of the specified array. 87 * If the collection fits in the specified array, it is returned therein. 88 * Otherwise, a new array is allocated with the runtime type of the 89 * specified array and the size of this collection. 90 * 91 * <p>If this collection fits in the specified array with room to spare 92 * (i.e., the array has more elements than this collection), the element 93 * in the array immediately following the end of the collection is set to 94 * <tt>null</tt>. (This is useful in determining the length of this 95 * collection <i>only</i> if the caller knows that this collection does 96 * not contain any <tt>null</tt> elements.) 97 * 98 * <p>If this collection makes any guarantees as to what order its elements 99 * are returned by its iterator, this method must return the elements in 100 * the same order. 101 * 102 * <p>Like the {@link #toArray()} method, this method acts as bridge between 103 * array-based and collection-based APIs. Further, this method allows 104 * precise control over the runtime type of the output array, and may, 105 * under certain circumstances, be used to save allocation costs. 106 * 107 * <p>Suppose <tt>x</tt> is a collection known to contain only strings. 108 * The following code can be used to dump the collection into a newly 109 * allocated array of <tt>string</tt>: 110 * 111 * <pre> 112 * string[] y = x.toArray(new string[0]);</pre> 113 * 114 * Note that <tt>toArray(new Object[0])</tt> is identical in function to 115 * <tt>toArray()</tt>. 116 * 117 * @param (T) the runtime type of the array to contain the collection 118 * @param a the array into which the elements of this collection are to be 119 * stored, if it is big enough; otherwise, a new array of the same 120 * runtime type is allocated for this purpose. 121 * @return an array containing all of the elements in this collection 122 * @throws ArrayStoreException if the runtime type of the specified array 123 * is not a supertype of the runtime type of every element in 124 * this collection 125 * @throws NullPointerException if the specified array is null 126 */ 127 // T[] toArray(T)(T[] a); 128 129 // Modification Operations 130 131 /** 132 * Ensures that this collection contains the specified element (optional 133 * operation). Returns <tt>true</tt> if this collection changed as a 134 * result of the call. (Returns <tt>false</tt> if this collection does 135 * not permit duplicates and already contains the specified element.)<p> 136 * 137 * Collections that support this operation may place limitations on what 138 * elements may be added to this collection. In particular, some 139 * collections will refuse to add <tt>null</tt> elements, and others will 140 * impose restrictions on the type of elements that may be added. 141 * Collection classes should clearly specify in their documentation any 142 * restrictions on what elements may be added.<p> 143 * 144 * If a collection refuses to add a particular element for any reason 145 * other than that it already contains the element, it <i>must</i> throw 146 * an exception (rather than returning <tt>false</tt>). This preserves 147 * the invariant that a collection always contains the specified element 148 * after this call returns. 149 * 150 * @param e element whose presence in this collection is to be ensured 151 * @return <tt>true</tt> if this collection changed as a result of the 152 * call 153 * @throws UnsupportedOperationException if the <tt>add</tt> operation 154 * is not supported by this collection 155 * @throws ClassCastException if the class of the specified element 156 * prevents it from being added to this collection 157 * @throws NullPointerException if the specified element is null and this 158 * collection does not permit null elements 159 * @throws IllegalArgumentException if some property of the element 160 * prevents it from being added to this collection 161 * @throws IllegalStateException if the element cannot be added at this 162 * time due to insertion restrictions 163 */ 164 bool add(E e); 165 166 /** 167 * Removes a single instance of the specified element from this 168 * collection, if it is present (optional operation). More formally, 169 * removes an element <tt>e</tt> such that 170 * <tt>(o==null ? e==null : o.equals(e))</tt>, if 171 * this collection contains one or more such elements. Returns 172 * <tt>true</tt> if this collection contained the specified element (or 173 * equivalently, if this collection changed as a result of the call). 174 * 175 * @param o element to be removed from this collection, if present 176 * @return <tt>true</tt> if an element was removed as a result of this call 177 * @throws ClassCastException if the type of the specified element 178 * is incompatible with this collection 179 * (<a href="#optional-restrictions">optional</a>) 180 * @throws NullPointerException if the specified element is null and this 181 * collection does not permit null elements 182 * (<a href="#optional-restrictions">optional</a>) 183 * @throws UnsupportedOperationException if the <tt>remove</tt> operation 184 * is not supported by this collection 185 */ 186 bool remove(E o); 187 188 189 // Bulk Operations 190 191 /** 192 * Returns <tt>true</tt> if this collection contains all of the elements 193 * in the specified collection. 194 * 195 * @param c collection to be checked for containment in this collection 196 * @return <tt>true</tt> if this collection contains all of the elements 197 * in the specified collection 198 * @throws ClassCastException if the types of one or more elements 199 * in the specified collection are incompatible with this 200 * collection 201 * (<a href="#optional-restrictions">optional</a>) 202 * @throws NullPointerException if the specified collection contains one 203 * or more null elements and this collection does not permit null 204 * elements 205 * (<a href="#optional-restrictions">optional</a>), 206 * or if the specified collection is null. 207 * @see #contains(Object) 208 */ 209 bool containsAll(Collection!E c); 210 211 /** 212 * Adds all of the elements in the specified collection to this collection 213 * (optional operation). The behavior of this operation is undefined if 214 * the specified collection is modified while the operation is in progress. 215 * (This implies that the behavior of this call is undefined if the 216 * specified collection is this collection, and this collection is 217 * nonempty.) 218 * 219 * @param c collection containing elements to be added to this collection 220 * @return <tt>true</tt> if this collection changed as a result of the call 221 * @throws UnsupportedOperationException if the <tt>addAll</tt> operation 222 * is not supported by this collection 223 * @throws ClassCastException if the class of an element of the specified 224 * collection prevents it from being added to this collection 225 * @throws NullPointerException if the specified collection contains a 226 * null element and this collection does not permit null elements, 227 * or if the specified collection is null 228 * @throws IllegalArgumentException if some property of an element of the 229 * specified collection prevents it from being added to this 230 * collection 231 * @throws IllegalStateException if not all the elements can be added at 232 * this time due to insertion restrictions 233 * @see #add(Object) 234 */ 235 bool addAll(Collection!E c); 236 bool addAll(E[] c); 237 238 /** 239 * Removes all of this collection's elements that are also contained in the 240 * specified collection (optional operation). After this call returns, 241 * this collection will contain no elements in common with the specified 242 * collection. 243 * 244 * @param c collection containing elements to be removed from this collection 245 * @return <tt>true</tt> if this collection changed as a result of the 246 * call 247 * @throws UnsupportedOperationException if the <tt>removeAll</tt> method 248 * is not supported by this collection 249 * @throws ClassCastException if the types of one or more elements 250 * in this collection are incompatible with the specified 251 * collection 252 * (<a href="#optional-restrictions">optional</a>) 253 * @throws NullPointerException if this collection contains one or more 254 * null elements and the specified collection does not support 255 * null elements 256 * (<a href="#optional-restrictions">optional</a>), 257 * or if the specified collection is null 258 * @see #remove(Object) 259 * @see #contains(Object) 260 */ 261 bool removeAll(Collection!E c); 262 263 /** 264 * Removes all of the elements of this collection that satisfy the given 265 * predicate. Errors or runtime exceptions thrown during iteration or by 266 * the predicate are relayed to the caller. 267 * 268 * @implSpec 269 * The default implementation traverses all elements of the collection using 270 * its {@link #iterator}. Each matching element is removed using 271 * {@link Iterator#remove()}. If the collection's iterator does not 272 * support removal then an {@code UnsupportedOperationException} will be 273 * thrown on the first matching element. 274 * 275 * @param filter a predicate which returns {@code true} for elements to be 276 * removed 277 * @return {@code true} if any elements were removed 278 * @throws NullPointerException if the specified filter is null 279 * @throws UnsupportedOperationException if elements cannot be removed 280 * from this collection. Implementations may throw this exception if a 281 * matching element cannot be removed or if, in general, removal is not 282 * supported. 283 * @since 1.8 284 */ 285 bool removeIf(Predicate!E filter); 286 287 /** 288 * Retains only the elements in this collection that are contained in the 289 * specified collection (optional operation). In other words, removes from 290 * this collection all of its elements that are not contained in the 291 * specified collection. 292 * 293 * @param c collection containing elements to be retained in this collection 294 * @return <tt>true</tt> if this collection changed as a result of the call 295 * @throws UnsupportedOperationException if the <tt>retainAll</tt> operation 296 * is not supported by this collection 297 * @throws ClassCastException if the types of one or more elements 298 * in this collection are incompatible with the specified 299 * collection 300 * (<a href="#optional-restrictions">optional</a>) 301 * @throws NullPointerException if this collection contains one or more 302 * null elements and the specified collection does not permit null 303 * elements 304 * (<a href="#optional-restrictions">optional</a>), 305 * or if the specified collection is null 306 * @see #remove(Object) 307 * @see #contains(Object) 308 */ 309 bool retainAll(Collection!E c); 310 311 /** 312 * Removes all of the elements from this collection (optional operation). 313 * The collection will be empty after this method returns. 314 * 315 * @throws UnsupportedOperationException if the <tt>clear</tt> operation 316 * is not supported by this collection 317 */ 318 void clear(); 319 320 // string toString(); 321 322 323 // Comparison and hashing 324 325 /** 326 * Compares the specified object with this collection for equality. <p> 327 * 328 * While the <tt>Collection</tt> interface adds no stipulations to the 329 * general contract for the <tt>Object.equals</tt>, programmers who 330 * implement the <tt>Collection</tt> interface "directly" (in other words, 331 * create a class that is a <tt>Collection</tt> but is not a <tt>Set</tt> 332 * or a <tt>List</tt>) must exercise care if they choose to override the 333 * <tt>Object.equals</tt>. It is not necessary to do so, and the simplest 334 * course of action is to rely on <tt>Object</tt>'s implementation, but 335 * the implementor may wish to implement a "value comparison" in place of 336 * the default "reference comparison." (The <tt>List</tt> and 337 * <tt>Set</tt> interfaces mandate such value comparisons.)<p> 338 * 339 * The general contract for the <tt>Object.equals</tt> method states that 340 * equals must be symmetric (in other words, <tt>a.equals(b)</tt> if and 341 * only if <tt>b.equals(a)</tt>). The contracts for <tt>List.equals</tt> 342 * and <tt>Set.equals</tt> state that lists are only equal to other lists, 343 * and sets to other sets. Thus, a custom <tt>equals</tt> method for a 344 * collection class that implements neither the <tt>List</tt> nor 345 * <tt>Set</tt> interface must return <tt>false</tt> when this collection 346 * is compared to any list or set. (By the same logic, it is not possible 347 * to write a class that correctly implements both the <tt>Set</tt> and 348 * <tt>List</tt> interfaces.) 349 * 350 * @param o object to be compared for equality with this collection 351 * @return <tt>true</tt> if the specified object is equal to this 352 * collection 353 * 354 * @see Object#equals(Object) 355 * @see Set#equals(Object) 356 * @see List#equals(Object) 357 */ 358 // bool opEquals(Object o); 359 360 /** 361 * Returns the hash code value for this collection. While the 362 * <tt>Collection</tt> interface adds no stipulations to the general 363 * contract for the <tt>Object.toHash</tt> method, programmers should 364 * take note that any class that overrides the <tt>Object.equals</tt> 365 * method must also override the <tt>Object.toHash</tt> method in order 366 * to satisfy the general contract for the <tt>Object.toHash</tt> method. 367 * In particular, <tt>c1.equals(c2)</tt> implies that 368 * <tt>c1.toHash()==c2.toHash()</tt>. 369 * 370 * @return the hash code value for this collection 371 * 372 * @see Object#toHash() 373 * @see Object#equals(Object) 374 */ 375 // size_t toHash() @trusted nothrow; 376 377 /** 378 * Creates a {@link Spliterator} over the elements in this collection. 379 * 380 * Implementations should document characteristic values reported by the 381 * spliterator. Such characteristic values are not required to be reported 382 * if the spliterator reports {@link Spliterator#SIZED} and this collection 383 * contains no elements. 384 * 385 * <p>The default implementation should be overridden by subclasses that 386 * can return a more efficient spliterator. In order to 387 * preserve expected laziness behavior for the {@link #stream()} and 388 * {@link #parallelStream()}} methods, spliterators should either have the 389 * characteristic of {@code IMMUTABLE} or {@code CONCURRENT}, or be 390 * <em><a href="Spliterator.html#binding">late-binding</a></em>. 391 * If none of these is practical, the overriding class should describe the 392 * spliterator's documented policy of binding and structural interference, 393 * and should override the {@link #stream()} and {@link #parallelStream()} 394 * methods to create streams using a {@code Supplier} of the spliterator, 395 * as in: 396 * <pre>{@code 397 * Stream!E s = StreamSupport.stream(() -> spliterator(), spliteratorCharacteristics) 398 * }</pre> 399 * <p>These requirements ensure that streams produced by the 400 * {@link #stream()} and {@link #parallelStream()} methods will reflect the 401 * contents of the collection as of initiation of the terminal stream 402 * operation. 403 * 404 * @implSpec 405 * The default implementation creates a 406 * <em><a href="Spliterator.html#binding">late-binding</a></em> spliterator 407 * from the collections's {@code Iterator}. The spliterator inherits the 408 * <em>fail-fast</em> properties of the collection's iterator. 409 * <p> 410 * The created {@code Spliterator} reports {@link Spliterator#SIZED}. 411 * 412 * @implNote 413 * The created {@code Spliterator} additionally reports 414 * {@link Spliterator#SUBSIZED}. 415 * 416 * <p>If a spliterator covers no elements then the reporting of additional 417 * characteristic values, beyond that of {@code SIZED} and {@code SUBSIZED}, 418 * does not aid clients to control, specialize or simplify computation. 419 * However, this does enable shared use of an immutable and empty 420 * spliterator instance (see {@link Spliterators#emptySpliterator()}) for 421 * empty collections, and enables clients to determine if such a spliterator 422 * covers no elements. 423 * 424 * @return a {@code Spliterator} over the elements in this collection 425 * @since 1.8 426 */ 427 // override 428 // final Spliterator!E spliterator() { 429 // return Spliterators.spliterator(this, 0); 430 // } 431 432 /** 433 * Returns a sequential {@code Stream} with this collection as its source. 434 * 435 * <p>This method should be overridden when the {@link #spliterator()} 436 * method cannot return a spliterator that is {@code IMMUTABLE}, 437 * {@code CONCURRENT}, or <em>late-binding</em>. (See {@link #spliterator()} 438 * for details.) 439 * 440 * @implSpec 441 * The default implementation creates a sequential {@code Stream} from the 442 * collection's {@code Spliterator}. 443 * 444 * @return a sequential {@code Stream} over the elements in this collection 445 * @since 1.8 446 */ 447 // final Stream!E stream() { 448 // return StreamSupport.stream(spliterator(), false); 449 // } 450 451 /** 452 * Returns a possibly parallel {@code Stream} with this collection as its 453 * source. It is allowable for this method to return a sequential stream. 454 * 455 * <p>This method should be overridden when the {@link #spliterator()} 456 * method cannot return a spliterator that is {@code IMMUTABLE}, 457 * {@code CONCURRENT}, or <em>late-binding</em>. (See {@link #spliterator()} 458 * for details.) 459 * 460 * @implSpec 461 * The default implementation creates a parallel {@code Stream} from the 462 * collection's {@code Spliterator}. 463 * 464 * @return a possibly parallel {@code Stream} over the elements in this 465 * collection 466 * @since 1.8 467 */ 468 // final Stream!E parallelStream() { 469 // return StreamSupport.stream(spliterator(), true); 470 // } 471 472 473 } 474 475