diff -r 836adbf7a2cd -r 3317bb8137f4 jdk/src/java.base/share/classes/java/util/RegularEnumSet.java --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/jdk/src/java.base/share/classes/java/util/RegularEnumSet.java Sun Aug 17 15:54:13 2014 +0100 @@ -0,0 +1,304 @@ +/* + * Copyright (c) 2003, 2012, Oracle and/or its affiliates. All rights reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. Oracle designates this + * particular file as subject to the "Classpath" exception as provided + * by Oracle in the LICENSE file that accompanied this code. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA + * or visit www.oracle.com if you need additional information or have any + * questions. + */ + +package java.util; + +/** + * Private implementation class for EnumSet, for "regular sized" enum types + * (i.e., those with 64 or fewer enum constants). + * + * @author Josh Bloch + * @since 1.5 + * @serial exclude + */ +class RegularEnumSet<E extends Enum<E>> extends EnumSet<E> { + private static final long serialVersionUID = 3411599620347842686L; + /** + * Bit vector representation of this set. The 2^k bit indicates the + * presence of universe[k] in this set. + */ + private long elements = 0L; + + RegularEnumSet(Class<E>elementType, Enum<?>[] universe) { + super(elementType, universe); + } + + void addRange(E from, E to) { + elements = (-1L >>> (from.ordinal() - to.ordinal() - 1)) << from.ordinal(); + } + + void addAll() { + if (universe.length != 0) + elements = -1L >>> -universe.length; + } + + void complement() { + if (universe.length != 0) { + elements = ~elements; + elements &= -1L >>> -universe.length; // Mask unused bits + } + } + + /** + * Returns an iterator over the elements contained in this set. The + * iterator traverses the elements in their <i>natural order</i> (which is + * the order in which the enum constants are declared). The returned + * Iterator is a "snapshot" iterator that will never throw {@link + * ConcurrentModificationException}; the elements are traversed as they + * existed when this call was invoked. + * + * @return an iterator over the elements contained in this set + */ + public Iterator<E> iterator() { + return new EnumSetIterator<>(); + } + + private class EnumSetIterator<E extends Enum<E>> implements Iterator<E> { + /** + * A bit vector representing the elements in the set not yet + * returned by this iterator. + */ + long unseen; + + /** + * The bit representing the last element returned by this iterator + * but not removed, or zero if no such element exists. + */ + long lastReturned = 0; + + EnumSetIterator() { + unseen = elements; + } + + public boolean hasNext() { + return unseen != 0; + } + + @SuppressWarnings("unchecked") + public E next() { + if (unseen == 0) + throw new NoSuchElementException(); + lastReturned = unseen & -unseen; + unseen -= lastReturned; + return (E) universe[Long.numberOfTrailingZeros(lastReturned)]; + } + + public void remove() { + if (lastReturned == 0) + throw new IllegalStateException(); + elements &= ~lastReturned; + lastReturned = 0; + } + } + + /** + * Returns the number of elements in this set. + * + * @return the number of elements in this set + */ + public int size() { + return Long.bitCount(elements); + } + + /** + * Returns <tt>true</tt> if this set contains no elements. + * + * @return <tt>true</tt> if this set contains no elements + */ + public boolean isEmpty() { + return elements == 0; + } + + /** + * Returns <tt>true</tt> if this set contains the specified element. + * + * @param e element to be checked for containment in this collection + * @return <tt>true</tt> if this set contains the specified element + */ + public boolean contains(Object e) { + if (e == null) + return false; + Class<?> eClass = e.getClass(); + if (eClass != elementType && eClass.getSuperclass() != elementType) + return false; + + return (elements & (1L << ((Enum<?>)e).ordinal())) != 0; + } + + // Modification Operations + + /** + * Adds the specified element to this set if it is not already present. + * + * @param e element to be added to this set + * @return <tt>true</tt> if the set changed as a result of the call + * + * @throws NullPointerException if <tt>e</tt> is null + */ + public boolean add(E e) { + typeCheck(e); + + long oldElements = elements; + elements |= (1L << ((Enum<?>)e).ordinal()); + return elements != oldElements; + } + + /** + * Removes the specified element from this set if it is present. + * + * @param e element to be removed from this set, if present + * @return <tt>true</tt> if the set contained the specified element + */ + public boolean remove(Object e) { + if (e == null) + return false; + Class<?> eClass = e.getClass(); + if (eClass != elementType && eClass.getSuperclass() != elementType) + return false; + + long oldElements = elements; + elements &= ~(1L << ((Enum<?>)e).ordinal()); + return elements != oldElements; + } + + // Bulk Operations + + /** + * Returns <tt>true</tt> if this set contains all of the elements + * in the specified collection. + * + * @param c collection to be checked for containment in this set + * @return <tt>true</tt> if this set contains all of the elements + * in the specified collection + * @throws NullPointerException if the specified collection is null + */ + public boolean containsAll(Collection<?> c) { + if (!(c instanceof RegularEnumSet)) + return super.containsAll(c); + + RegularEnumSet<?> es = (RegularEnumSet<?>)c; + if (es.elementType != elementType) + return es.isEmpty(); + + return (es.elements & ~elements) == 0; + } + + /** + * Adds all of the elements in the specified collection to this set. + * + * @param c collection whose elements are to be added to this set + * @return <tt>true</tt> if this set changed as a result of the call + * @throws NullPointerException if the specified collection or any + * of its elements are null + */ + public boolean addAll(Collection<? extends E> c) { + if (!(c instanceof RegularEnumSet)) + return super.addAll(c); + + RegularEnumSet<?> es = (RegularEnumSet<?>)c; + if (es.elementType != elementType) { + if (es.isEmpty()) + return false; + else + throw new ClassCastException( + es.elementType + " != " + elementType); + } + + long oldElements = elements; + elements |= es.elements; + return elements != oldElements; + } + + /** + * Removes from this set all of its elements that are contained in + * the specified collection. + * + * @param c elements to be removed from this set + * @return <tt>true</tt> if this set changed as a result of the call + * @throws NullPointerException if the specified collection is null + */ + public boolean removeAll(Collection<?> c) { + if (!(c instanceof RegularEnumSet)) + return super.removeAll(c); + + RegularEnumSet<?> es = (RegularEnumSet<?>)c; + if (es.elementType != elementType) + return false; + + long oldElements = elements; + elements &= ~es.elements; + return elements != oldElements; + } + + /** + * Retains only the elements in this set that are contained in the + * specified collection. + * + * @param c elements to be retained in this set + * @return <tt>true</tt> if this set changed as a result of the call + * @throws NullPointerException if the specified collection is null + */ + public boolean retainAll(Collection<?> c) { + if (!(c instanceof RegularEnumSet)) + return super.retainAll(c); + + RegularEnumSet<?> es = (RegularEnumSet<?>)c; + if (es.elementType != elementType) { + boolean changed = (elements != 0); + elements = 0; + return changed; + } + + long oldElements = elements; + elements &= es.elements; + return elements != oldElements; + } + + /** + * Removes all of the elements from this set. + */ + public void clear() { + elements = 0; + } + + /** + * Compares the specified object with this set for equality. Returns + * <tt>true</tt> if the given object is also a set, the two sets have + * the same size, and every member of the given set is contained in + * this set. + * + * @param o object to be compared for equality with this set + * @return <tt>true</tt> if the specified object is equal to this set + */ + public boolean equals(Object o) { + if (!(o instanceof RegularEnumSet)) + return super.equals(o); + + RegularEnumSet<?> es = (RegularEnumSet<?>)o; + if (es.elementType != elementType) + return elements == 0 && es.elements == 0; + return es.elements == elements; + } +}