jtulach@1292: /*
jtulach@1292:  * Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved.
jtulach@1292:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
jtulach@1292:  *
jtulach@1292:  * This code is free software; you can redistribute it and/or modify it
jtulach@1292:  * under the terms of the GNU General Public License version 2 only, as
jtulach@1292:  * published by the Free Software Foundation.  Oracle designates this
jtulach@1292:  * particular file as subject to the "Classpath" exception as provided
jtulach@1292:  * by Oracle in the LICENSE file that accompanied this code.
jtulach@1292:  *
jtulach@1292:  * This code is distributed in the hope that it will be useful, but WITHOUT
jtulach@1292:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
jtulach@1292:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
jtulach@1292:  * version 2 for more details (a copy is included in the LICENSE file that
jtulach@1292:  * accompanied this code).
jtulach@1292:  *
jtulach@1292:  * You should have received a copy of the GNU General Public License version
jtulach@1292:  * 2 along with this work; if not, write to the Free Software Foundation,
jtulach@1292:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
jtulach@1292:  *
jtulach@1292:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
jtulach@1292:  * or visit www.oracle.com if you need additional information or have any
jtulach@1292:  * questions.
jtulach@1292:  */
jtulach@1292: 
jtulach@1292: package java.util;
jtulach@1292: 
jtulach@1292: /**
jtulach@1292:  * Private implementation class for EnumSet, for "regular sized" enum types
jtulach@1292:  * (i.e., those with 64 or fewer enum constants).
jtulach@1292:  *
jtulach@1292:  * @author Josh Bloch
jtulach@1292:  * @since 1.5
jtulach@1292:  * @serial exclude
jtulach@1292:  */
jtulach@1292: class RegularEnumSet<E extends Enum<E>> extends EnumSet<E> {
jtulach@1292:     private static final long serialVersionUID = 3411599620347842686L;
jtulach@1292:     /**
jtulach@1292:      * Bit vector representation of this set.  The 2^k bit indicates the
jtulach@1292:      * presence of universe[k] in this set.
jtulach@1292:      */
jtulach@1292:     private long elements = 0L;
jtulach@1292: 
jtulach@1292:     RegularEnumSet(Class<E>elementType, Enum[] universe) {
jtulach@1292:         super(elementType, universe);
jtulach@1292:     }
jtulach@1292: 
jtulach@1292:     void addRange(E from, E to) {
jtulach@1292:         elements = (-1L >>>  (from.ordinal() - to.ordinal() - 1)) << from.ordinal();
jtulach@1292:     }
jtulach@1292: 
jtulach@1292:     void addAll() {
jtulach@1292:         if (universe.length != 0)
jtulach@1292:             elements = -1L >>> -universe.length;
jtulach@1292:     }
jtulach@1292: 
jtulach@1292:     void complement() {
jtulach@1292:         if (universe.length != 0) {
jtulach@1292:             elements = ~elements;
jtulach@1292:             elements &= -1L >>> -universe.length;  // Mask unused bits
jtulach@1292:         }
jtulach@1292:     }
jtulach@1292: 
jtulach@1292:     /**
jtulach@1292:      * Returns an iterator over the elements contained in this set.  The
jtulach@1292:      * iterator traverses the elements in their <i>natural order</i> (which is
jtulach@1292:      * the order in which the enum constants are declared). The returned
jtulach@1292:      * Iterator is a "snapshot" iterator that will never throw {@link
jtulach@1292:      * ConcurrentModificationException}; the elements are traversed as they
jtulach@1292:      * existed when this call was invoked.
jtulach@1292:      *
jtulach@1292:      * @return an iterator over the elements contained in this set
jtulach@1292:      */
jtulach@1292:     public Iterator<E> iterator() {
jtulach@1292:         return new EnumSetIterator<>();
jtulach@1292:     }
jtulach@1292: 
jtulach@1292:     private class EnumSetIterator<E extends Enum<E>> implements Iterator<E> {
jtulach@1292:         /**
jtulach@1292:          * A bit vector representing the elements in the set not yet
jtulach@1292:          * returned by this iterator.
jtulach@1292:          */
jtulach@1292:         long unseen;
jtulach@1292: 
jtulach@1292:         /**
jtulach@1292:          * The bit representing the last element returned by this iterator
jtulach@1292:          * but not removed, or zero if no such element exists.
jtulach@1292:          */
jtulach@1292:         long lastReturned = 0;
jtulach@1292: 
jtulach@1292:         EnumSetIterator() {
jtulach@1292:             unseen = elements;
jtulach@1292:         }
jtulach@1292: 
jtulach@1292:         public boolean hasNext() {
jtulach@1292:             return unseen != 0;
jtulach@1292:         }
jtulach@1292: 
jtulach@1292:         public E next() {
jtulach@1292:             if (unseen == 0)
jtulach@1292:                 throw new NoSuchElementException();
jtulach@1292:             lastReturned = unseen & -unseen;
jtulach@1292:             unseen -= lastReturned;
jtulach@1292:             return (E) universe[Long.numberOfTrailingZeros(lastReturned)];
jtulach@1292:         }
jtulach@1292: 
jtulach@1292:         public void remove() {
jtulach@1292:             if (lastReturned == 0)
jtulach@1292:                 throw new IllegalStateException();
jtulach@1292:             elements &= ~lastReturned;
jtulach@1292:             lastReturned = 0;
jtulach@1292:         }
jtulach@1292:     }
jtulach@1292: 
jtulach@1292:     /**
jtulach@1292:      * Returns the number of elements in this set.
jtulach@1292:      *
jtulach@1292:      * @return the number of elements in this set
jtulach@1292:      */
jtulach@1292:     public int size() {
jtulach@1292:         return Long.bitCount(elements);
jtulach@1292:     }
jtulach@1292: 
jtulach@1292:     /**
jtulach@1292:      * Returns <tt>true</tt> if this set contains no elements.
jtulach@1292:      *
jtulach@1292:      * @return <tt>true</tt> if this set contains no elements
jtulach@1292:      */
jtulach@1292:     public boolean isEmpty() {
jtulach@1292:         return elements == 0;
jtulach@1292:     }
jtulach@1292: 
jtulach@1292:     /**
jtulach@1292:      * Returns <tt>true</tt> if this set contains the specified element.
jtulach@1292:      *
jtulach@1292:      * @param e element to be checked for containment in this collection
jtulach@1292:      * @return <tt>true</tt> if this set contains the specified element
jtulach@1292:      */
jtulach@1292:     public boolean contains(Object e) {
jtulach@1292:         if (e == null)
jtulach@1292:             return false;
jtulach@1292:         Class eClass = e.getClass();
jtulach@1292:         if (eClass != elementType && eClass.getSuperclass() != elementType)
jtulach@1292:             return false;
jtulach@1292: 
jtulach@1292:         return (elements & (1L << ((Enum)e).ordinal())) != 0;
jtulach@1292:     }
jtulach@1292: 
jtulach@1292:     // Modification Operations
jtulach@1292: 
jtulach@1292:     /**
jtulach@1292:      * Adds the specified element to this set if it is not already present.
jtulach@1292:      *
jtulach@1292:      * @param e element to be added to this set
jtulach@1292:      * @return <tt>true</tt> if the set changed as a result of the call
jtulach@1292:      *
jtulach@1292:      * @throws NullPointerException if <tt>e</tt> is null
jtulach@1292:      */
jtulach@1292:     public boolean add(E e) {
jtulach@1292:         typeCheck(e);
jtulach@1292: 
jtulach@1292:         long oldElements = elements;
jtulach@1292:         elements |= (1L << ((Enum)e).ordinal());
jtulach@1292:         return elements != oldElements;
jtulach@1292:     }
jtulach@1292: 
jtulach@1292:     /**
jtulach@1292:      * Removes the specified element from this set if it is present.
jtulach@1292:      *
jtulach@1292:      * @param e element to be removed from this set, if present
jtulach@1292:      * @return <tt>true</tt> if the set contained the specified element
jtulach@1292:      */
jtulach@1292:     public boolean remove(Object e) {
jtulach@1292:         if (e == null)
jtulach@1292:             return false;
jtulach@1292:         Class eClass = e.getClass();
jtulach@1292:         if (eClass != elementType && eClass.getSuperclass() != elementType)
jtulach@1292:             return false;
jtulach@1292: 
jtulach@1292:         long oldElements = elements;
jtulach@1292:         elements &= ~(1L << ((Enum)e).ordinal());
jtulach@1292:         return elements != oldElements;
jtulach@1292:     }
jtulach@1292: 
jtulach@1292:     // Bulk Operations
jtulach@1292: 
jtulach@1292:     /**
jtulach@1292:      * Returns <tt>true</tt> if this set contains all of the elements
jtulach@1292:      * in the specified collection.
jtulach@1292:      *
jtulach@1292:      * @param c collection to be checked for containment in this set
jtulach@1292:      * @return <tt>true</tt> if this set contains all of the elements
jtulach@1292:      *        in the specified collection
jtulach@1292:      * @throws NullPointerException if the specified collection is null
jtulach@1292:      */
jtulach@1292:     public boolean containsAll(Collection<?> c) {
jtulach@1292:         if (!(c instanceof RegularEnumSet))
jtulach@1292:             return super.containsAll(c);
jtulach@1292: 
jtulach@1292:         RegularEnumSet es = (RegularEnumSet)c;
jtulach@1292:         if (es.elementType != elementType)
jtulach@1292:             return es.isEmpty();
jtulach@1292: 
jtulach@1292:         return (es.elements & ~elements) == 0;
jtulach@1292:     }
jtulach@1292: 
jtulach@1292:     /**
jtulach@1292:      * Adds all of the elements in the specified collection to this set.
jtulach@1292:      *
jtulach@1292:      * @param c collection whose elements are to be added to this set
jtulach@1292:      * @return <tt>true</tt> if this set changed as a result of the call
jtulach@1292:      * @throws NullPointerException if the specified collection or any
jtulach@1292:      *     of its elements are null
jtulach@1292:      */
jtulach@1292:     public boolean addAll(Collection<? extends E> c) {
jtulach@1292:         if (!(c instanceof RegularEnumSet))
jtulach@1292:             return super.addAll(c);
jtulach@1292: 
jtulach@1292:         RegularEnumSet es = (RegularEnumSet)c;
jtulach@1292:         if (es.elementType != elementType) {
jtulach@1292:             if (es.isEmpty())
jtulach@1292:                 return false;
jtulach@1292:             else
jtulach@1292:                 throw new ClassCastException(
jtulach@1292:                     es.elementType + " != " + elementType);
jtulach@1292:         }
jtulach@1292: 
jtulach@1292:         long oldElements = elements;
jtulach@1292:         elements |= es.elements;
jtulach@1292:         return elements != oldElements;
jtulach@1292:     }
jtulach@1292: 
jtulach@1292:     /**
jtulach@1292:      * Removes from this set all of its elements that are contained in
jtulach@1292:      * the specified collection.
jtulach@1292:      *
jtulach@1292:      * @param c elements to be removed from this set
jtulach@1292:      * @return <tt>true</tt> if this set changed as a result of the call
jtulach@1292:      * @throws NullPointerException if the specified collection is null
jtulach@1292:      */
jtulach@1292:     public boolean removeAll(Collection<?> c) {
jtulach@1292:         if (!(c instanceof RegularEnumSet))
jtulach@1292:             return super.removeAll(c);
jtulach@1292: 
jtulach@1292:         RegularEnumSet es = (RegularEnumSet)c;
jtulach@1292:         if (es.elementType != elementType)
jtulach@1292:             return false;
jtulach@1292: 
jtulach@1292:         long oldElements = elements;
jtulach@1292:         elements &= ~es.elements;
jtulach@1292:         return elements != oldElements;
jtulach@1292:     }
jtulach@1292: 
jtulach@1292:     /**
jtulach@1292:      * Retains only the elements in this set that are contained in the
jtulach@1292:      * specified collection.
jtulach@1292:      *
jtulach@1292:      * @param c elements to be retained in this set
jtulach@1292:      * @return <tt>true</tt> if this set changed as a result of the call
jtulach@1292:      * @throws NullPointerException if the specified collection is null
jtulach@1292:      */
jtulach@1292:     public boolean retainAll(Collection<?> c) {
jtulach@1292:         if (!(c instanceof RegularEnumSet))
jtulach@1292:             return super.retainAll(c);
jtulach@1292: 
jtulach@1292:         RegularEnumSet<?> es = (RegularEnumSet<?>)c;
jtulach@1292:         if (es.elementType != elementType) {
jtulach@1292:             boolean changed = (elements != 0);
jtulach@1292:             elements = 0;
jtulach@1292:             return changed;
jtulach@1292:         }
jtulach@1292: 
jtulach@1292:         long oldElements = elements;
jtulach@1292:         elements &= es.elements;
jtulach@1292:         return elements != oldElements;
jtulach@1292:     }
jtulach@1292: 
jtulach@1292:     /**
jtulach@1292:      * Removes all of the elements from this set.
jtulach@1292:      */
jtulach@1292:     public void clear() {
jtulach@1292:         elements = 0;
jtulach@1292:     }
jtulach@1292: 
jtulach@1292:     /**
jtulach@1292:      * Compares the specified object with this set for equality.  Returns
jtulach@1292:      * <tt>true</tt> if the given object is also a set, the two sets have
jtulach@1292:      * the same size, and every member of the given set is contained in
jtulach@1292:      * this set.
jtulach@1292:      *
jtulach@1292:      * @param e object to be compared for equality with this set
jtulach@1292:      * @return <tt>true</tt> if the specified object is equal to this set
jtulach@1292:      */
jtulach@1292:     public boolean equals(Object o) {
jtulach@1292:         if (!(o instanceof RegularEnumSet))
jtulach@1292:             return super.equals(o);
jtulach@1292: 
jtulach@1292:         RegularEnumSet es = (RegularEnumSet)o;
jtulach@1292:         if (es.elementType != elementType)
jtulach@1292:             return elements == 0 && es.elements == 0;
jtulach@1292:         return es.elements == elements;
jtulach@1292:     }
jtulach@1292: }