1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/rt/emul/compact/src/main/java/java/util/Set.java Tue Feb 26 16:54:16 2013 +0100
1.3 @@ -0,0 +1,385 @@
1.4 +/*
1.5 + * Copyright (c) 1997, 2006, Oracle and/or its affiliates. All rights reserved.
1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 + *
1.8 + * This code is free software; you can redistribute it and/or modify it
1.9 + * under the terms of the GNU General Public License version 2 only, as
1.10 + * published by the Free Software Foundation. Oracle designates this
1.11 + * particular file as subject to the "Classpath" exception as provided
1.12 + * by Oracle in the LICENSE file that accompanied this code.
1.13 + *
1.14 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.15 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.16 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.17 + * version 2 for more details (a copy is included in the LICENSE file that
1.18 + * accompanied this code).
1.19 + *
1.20 + * You should have received a copy of the GNU General Public License version
1.21 + * 2 along with this work; if not, write to the Free Software Foundation,
1.22 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.23 + *
1.24 + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
1.25 + * or visit www.oracle.com if you need additional information or have any
1.26 + * questions.
1.27 + */
1.28 +
1.29 +package java.util;
1.30 +
1.31 +/**
1.32 + * A collection that contains no duplicate elements. More formally, sets
1.33 + * contain no pair of elements <code>e1</code> and <code>e2</code> such that
1.34 + * <code>e1.equals(e2)</code>, and at most one null element. As implied by
1.35 + * its name, this interface models the mathematical <i>set</i> abstraction.
1.36 + *
1.37 + * <p>The <tt>Set</tt> interface places additional stipulations, beyond those
1.38 + * inherited from the <tt>Collection</tt> interface, on the contracts of all
1.39 + * constructors and on the contracts of the <tt>add</tt>, <tt>equals</tt> and
1.40 + * <tt>hashCode</tt> methods. Declarations for other inherited methods are
1.41 + * also included here for convenience. (The specifications accompanying these
1.42 + * declarations have been tailored to the <tt>Set</tt> interface, but they do
1.43 + * not contain any additional stipulations.)
1.44 + *
1.45 + * <p>The additional stipulation on constructors is, not surprisingly,
1.46 + * that all constructors must create a set that contains no duplicate elements
1.47 + * (as defined above).
1.48 + *
1.49 + * <p>Note: Great care must be exercised if mutable objects are used as set
1.50 + * elements. The behavior of a set is not specified if the value of an object
1.51 + * is changed in a manner that affects <tt>equals</tt> comparisons while the
1.52 + * object is an element in the set. A special case of this prohibition is
1.53 + * that it is not permissible for a set to contain itself as an element.
1.54 + *
1.55 + * <p>Some set implementations have restrictions on the elements that
1.56 + * they may contain. For example, some implementations prohibit null elements,
1.57 + * and some have restrictions on the types of their elements. Attempting to
1.58 + * add an ineligible element throws an unchecked exception, typically
1.59 + * <tt>NullPointerException</tt> or <tt>ClassCastException</tt>. Attempting
1.60 + * to query the presence of an ineligible element may throw an exception,
1.61 + * or it may simply return false; some implementations will exhibit the former
1.62 + * behavior and some will exhibit the latter. More generally, attempting an
1.63 + * operation on an ineligible element whose completion would not result in
1.64 + * the insertion of an ineligible element into the set may throw an
1.65 + * exception or it may succeed, at the option of the implementation.
1.66 + * Such exceptions are marked as "optional" in the specification for this
1.67 + * interface.
1.68 + *
1.69 + * <p>This interface is a member of the
1.70 + * <a href="{@docRoot}/../technotes/guides/collections/index.html">
1.71 + * Java Collections Framework</a>.
1.72 + *
1.73 + * @param <E> the type of elements maintained by this set
1.74 + *
1.75 + * @author Josh Bloch
1.76 + * @author Neal Gafter
1.77 + * @see Collection
1.78 + * @see List
1.79 + * @see SortedSet
1.80 + * @see HashSet
1.81 + * @see TreeSet
1.82 + * @see AbstractSet
1.83 + * @see Collections#singleton(java.lang.Object)
1.84 + * @see Collections#EMPTY_SET
1.85 + * @since 1.2
1.86 + */
1.87 +
1.88 +public interface Set<E> extends Collection<E> {
1.89 + // Query Operations
1.90 +
1.91 + /**
1.92 + * Returns the number of elements in this set (its cardinality). If this
1.93 + * set contains more than <tt>Integer.MAX_VALUE</tt> elements, returns
1.94 + * <tt>Integer.MAX_VALUE</tt>.
1.95 + *
1.96 + * @return the number of elements in this set (its cardinality)
1.97 + */
1.98 + int size();
1.99 +
1.100 + /**
1.101 + * Returns <tt>true</tt> if this set contains no elements.
1.102 + *
1.103 + * @return <tt>true</tt> if this set contains no elements
1.104 + */
1.105 + boolean isEmpty();
1.106 +
1.107 + /**
1.108 + * Returns <tt>true</tt> if this set contains the specified element.
1.109 + * More formally, returns <tt>true</tt> if and only if this set
1.110 + * contains an element <tt>e</tt> such that
1.111 + * <tt>(o==null ? e==null : o.equals(e))</tt>.
1.112 + *
1.113 + * @param o element whose presence in this set is to be tested
1.114 + * @return <tt>true</tt> if this set contains the specified element
1.115 + * @throws ClassCastException if the type of the specified element
1.116 + * is incompatible with this set
1.117 + * (<a href="Collection.html#optional-restrictions">optional</a>)
1.118 + * @throws NullPointerException if the specified element is null and this
1.119 + * set does not permit null elements
1.120 + * (<a href="Collection.html#optional-restrictions">optional</a>)
1.121 + */
1.122 + boolean contains(Object o);
1.123 +
1.124 + /**
1.125 + * Returns an iterator over the elements in this set. The elements are
1.126 + * returned in no particular order (unless this set is an instance of some
1.127 + * class that provides a guarantee).
1.128 + *
1.129 + * @return an iterator over the elements in this set
1.130 + */
1.131 + Iterator<E> iterator();
1.132 +
1.133 + /**
1.134 + * Returns an array containing all of the elements in this set.
1.135 + * If this set makes any guarantees as to what order its elements
1.136 + * are returned by its iterator, this method must return the
1.137 + * elements in the same order.
1.138 + *
1.139 + * <p>The returned array will be "safe" in that no references to it
1.140 + * are maintained by this set. (In other words, this method must
1.141 + * allocate a new array even if this set is backed by an array).
1.142 + * The caller is thus free to modify the returned array.
1.143 + *
1.144 + * <p>This method acts as bridge between array-based and collection-based
1.145 + * APIs.
1.146 + *
1.147 + * @return an array containing all the elements in this set
1.148 + */
1.149 + Object[] toArray();
1.150 +
1.151 + /**
1.152 + * Returns an array containing all of the elements in this set; the
1.153 + * runtime type of the returned array is that of the specified array.
1.154 + * If the set fits in the specified array, it is returned therein.
1.155 + * Otherwise, a new array is allocated with the runtime type of the
1.156 + * specified array and the size of this set.
1.157 + *
1.158 + * <p>If this set fits in the specified array with room to spare
1.159 + * (i.e., the array has more elements than this set), the element in
1.160 + * the array immediately following the end of the set is set to
1.161 + * <tt>null</tt>. (This is useful in determining the length of this
1.162 + * set <i>only</i> if the caller knows that this set does not contain
1.163 + * any null elements.)
1.164 + *
1.165 + * <p>If this set makes any guarantees as to what order its elements
1.166 + * are returned by its iterator, this method must return the elements
1.167 + * in the same order.
1.168 + *
1.169 + * <p>Like the {@link #toArray()} method, this method acts as bridge between
1.170 + * array-based and collection-based APIs. Further, this method allows
1.171 + * precise control over the runtime type of the output array, and may,
1.172 + * under certain circumstances, be used to save allocation costs.
1.173 + *
1.174 + * <p>Suppose <tt>x</tt> is a set known to contain only strings.
1.175 + * The following code can be used to dump the set into a newly allocated
1.176 + * array of <tt>String</tt>:
1.177 + *
1.178 + * <pre>
1.179 + * String[] y = x.toArray(new String[0]);</pre>
1.180 + *
1.181 + * Note that <tt>toArray(new Object[0])</tt> is identical in function to
1.182 + * <tt>toArray()</tt>.
1.183 + *
1.184 + * @param a the array into which the elements of this set are to be
1.185 + * stored, if it is big enough; otherwise, a new array of the same
1.186 + * runtime type is allocated for this purpose.
1.187 + * @return an array containing all the elements in this set
1.188 + * @throws ArrayStoreException if the runtime type of the specified array
1.189 + * is not a supertype of the runtime type of every element in this
1.190 + * set
1.191 + * @throws NullPointerException if the specified array is null
1.192 + */
1.193 + <T> T[] toArray(T[] a);
1.194 +
1.195 +
1.196 + // Modification Operations
1.197 +
1.198 + /**
1.199 + * Adds the specified element to this set if it is not already present
1.200 + * (optional operation). More formally, adds the specified element
1.201 + * <tt>e</tt> to this set if the set contains no element <tt>e2</tt>
1.202 + * such that
1.203 + * <tt>(e==null ? e2==null : e.equals(e2))</tt>.
1.204 + * If this set already contains the element, the call leaves the set
1.205 + * unchanged and returns <tt>false</tt>. In combination with the
1.206 + * restriction on constructors, this ensures that sets never contain
1.207 + * duplicate elements.
1.208 + *
1.209 + * <p>The stipulation above does not imply that sets must accept all
1.210 + * elements; sets may refuse to add any particular element, including
1.211 + * <tt>null</tt>, and throw an exception, as described in the
1.212 + * specification for {@link Collection#add Collection.add}.
1.213 + * Individual set implementations should clearly document any
1.214 + * restrictions on the elements that they may contain.
1.215 + *
1.216 + * @param e element to be added to this set
1.217 + * @return <tt>true</tt> if this set did not already contain the specified
1.218 + * element
1.219 + * @throws UnsupportedOperationException if the <tt>add</tt> operation
1.220 + * is not supported by this set
1.221 + * @throws ClassCastException if the class of the specified element
1.222 + * prevents it from being added to this set
1.223 + * @throws NullPointerException if the specified element is null and this
1.224 + * set does not permit null elements
1.225 + * @throws IllegalArgumentException if some property of the specified element
1.226 + * prevents it from being added to this set
1.227 + */
1.228 + boolean add(E e);
1.229 +
1.230 +
1.231 + /**
1.232 + * Removes the specified element from this set if it is present
1.233 + * (optional operation). More formally, removes an element <tt>e</tt>
1.234 + * such that
1.235 + * <tt>(o==null ? e==null : o.equals(e))</tt>, if
1.236 + * this set contains such an element. Returns <tt>true</tt> if this set
1.237 + * contained the element (or equivalently, if this set changed as a
1.238 + * result of the call). (This set will not contain the element once the
1.239 + * call returns.)
1.240 + *
1.241 + * @param o object to be removed from this set, if present
1.242 + * @return <tt>true</tt> if this set contained the specified element
1.243 + * @throws ClassCastException if the type of the specified element
1.244 + * is incompatible with this set
1.245 + * (<a href="Collection.html#optional-restrictions">optional</a>)
1.246 + * @throws NullPointerException if the specified element is null and this
1.247 + * set does not permit null elements
1.248 + * (<a href="Collection.html#optional-restrictions">optional</a>)
1.249 + * @throws UnsupportedOperationException if the <tt>remove</tt> operation
1.250 + * is not supported by this set
1.251 + */
1.252 + boolean remove(Object o);
1.253 +
1.254 +
1.255 + // Bulk Operations
1.256 +
1.257 + /**
1.258 + * Returns <tt>true</tt> if this set contains all of the elements of the
1.259 + * specified collection. If the specified collection is also a set, this
1.260 + * method returns <tt>true</tt> if it is a <i>subset</i> of this set.
1.261 + *
1.262 + * @param c collection to be checked for containment in this set
1.263 + * @return <tt>true</tt> if this set contains all of the elements of the
1.264 + * specified collection
1.265 + * @throws ClassCastException if the types of one or more elements
1.266 + * in the specified collection are incompatible with this
1.267 + * set
1.268 + * (<a href="Collection.html#optional-restrictions">optional</a>)
1.269 + * @throws NullPointerException if the specified collection contains one
1.270 + * or more null elements and this set does not permit null
1.271 + * elements
1.272 + * (<a href="Collection.html#optional-restrictions">optional</a>),
1.273 + * or if the specified collection is null
1.274 + * @see #contains(Object)
1.275 + */
1.276 + boolean containsAll(Collection<?> c);
1.277 +
1.278 + /**
1.279 + * Adds all of the elements in the specified collection to this set if
1.280 + * they're not already present (optional operation). If the specified
1.281 + * collection is also a set, the <tt>addAll</tt> operation effectively
1.282 + * modifies this set so that its value is the <i>union</i> of the two
1.283 + * sets. The behavior of this operation is undefined if the specified
1.284 + * collection is modified while the operation is in progress.
1.285 + *
1.286 + * @param c collection containing elements to be added to this set
1.287 + * @return <tt>true</tt> if this set changed as a result of the call
1.288 + *
1.289 + * @throws UnsupportedOperationException if the <tt>addAll</tt> operation
1.290 + * is not supported by this set
1.291 + * @throws ClassCastException if the class of an element of the
1.292 + * specified collection prevents it from being added to this set
1.293 + * @throws NullPointerException if the specified collection contains one
1.294 + * or more null elements and this set does not permit null
1.295 + * elements, or if the specified collection is null
1.296 + * @throws IllegalArgumentException if some property of an element of the
1.297 + * specified collection prevents it from being added to this set
1.298 + * @see #add(Object)
1.299 + */
1.300 + boolean addAll(Collection<? extends E> c);
1.301 +
1.302 + /**
1.303 + * Retains only the elements in this set that are contained in the
1.304 + * specified collection (optional operation). In other words, removes
1.305 + * from this set all of its elements that are not contained in the
1.306 + * specified collection. If the specified collection is also a set, this
1.307 + * operation effectively modifies this set so that its value is the
1.308 + * <i>intersection</i> of the two sets.
1.309 + *
1.310 + * @param c collection containing elements to be retained in this set
1.311 + * @return <tt>true</tt> if this set changed as a result of the call
1.312 + * @throws UnsupportedOperationException if the <tt>retainAll</tt> operation
1.313 + * is not supported by this set
1.314 + * @throws ClassCastException if the class of an element of this set
1.315 + * is incompatible with the specified collection
1.316 + * (<a href="Collection.html#optional-restrictions">optional</a>)
1.317 + * @throws NullPointerException if this set contains a null element and the
1.318 + * specified collection does not permit null elements
1.319 + * (<a href="Collection.html#optional-restrictions">optional</a>),
1.320 + * or if the specified collection is null
1.321 + * @see #remove(Object)
1.322 + */
1.323 + boolean retainAll(Collection<?> c);
1.324 +
1.325 + /**
1.326 + * Removes from this set all of its elements that are contained in the
1.327 + * specified collection (optional operation). If the specified
1.328 + * collection is also a set, this operation effectively modifies this
1.329 + * set so that its value is the <i>asymmetric set difference</i> of
1.330 + * the two sets.
1.331 + *
1.332 + * @param c collection containing elements to be removed from this set
1.333 + * @return <tt>true</tt> if this set changed as a result of the call
1.334 + * @throws UnsupportedOperationException if the <tt>removeAll</tt> operation
1.335 + * is not supported by this set
1.336 + * @throws ClassCastException if the class of an element of this set
1.337 + * is incompatible with the specified collection
1.338 + * (<a href="Collection.html#optional-restrictions">optional</a>)
1.339 + * @throws NullPointerException if this set contains a null element and the
1.340 + * specified collection does not permit null elements
1.341 + * (<a href="Collection.html#optional-restrictions">optional</a>),
1.342 + * or if the specified collection is null
1.343 + * @see #remove(Object)
1.344 + * @see #contains(Object)
1.345 + */
1.346 + boolean removeAll(Collection<?> c);
1.347 +
1.348 + /**
1.349 + * Removes all of the elements from this set (optional operation).
1.350 + * The set will be empty after this call returns.
1.351 + *
1.352 + * @throws UnsupportedOperationException if the <tt>clear</tt> method
1.353 + * is not supported by this set
1.354 + */
1.355 + void clear();
1.356 +
1.357 +
1.358 + // Comparison and hashing
1.359 +
1.360 + /**
1.361 + * Compares the specified object with this set for equality. Returns
1.362 + * <tt>true</tt> if the specified object is also a set, the two sets
1.363 + * have the same size, and every member of the specified set is
1.364 + * contained in this set (or equivalently, every member of this set is
1.365 + * contained in the specified set). This definition ensures that the
1.366 + * equals method works properly across different implementations of the
1.367 + * set interface.
1.368 + *
1.369 + * @param o object to be compared for equality with this set
1.370 + * @return <tt>true</tt> if the specified object is equal to this set
1.371 + */
1.372 + boolean equals(Object o);
1.373 +
1.374 + /**
1.375 + * Returns the hash code value for this set. The hash code of a set is
1.376 + * defined to be the sum of the hash codes of the elements in the set,
1.377 + * where the hash code of a <tt>null</tt> element is defined to be zero.
1.378 + * This ensures that <tt>s1.equals(s2)</tt> implies that
1.379 + * <tt>s1.hashCode()==s2.hashCode()</tt> for any two sets <tt>s1</tt>
1.380 + * and <tt>s2</tt>, as required by the general contract of
1.381 + * {@link Object#hashCode}.
1.382 + *
1.383 + * @return the hash code value for this set
1.384 + * @see Object#equals(Object)
1.385 + * @see Set#equals(Object)
1.386 + */
1.387 + int hashCode();
1.388 +}