- /*
- * @(#)JumboEnumSet.java 1.8 04/05/28
- *
- * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
- * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
- */
-
- package java.util;
-
- /**
- * Private implementation class for EnumSet, for "jumbo" enum types
- * (i.e., those with more than 64 elements).
- *
- * @author Josh Bloch
- * @since 1.5
- * @serial exclude
- */
- class JumboEnumSet<E extends Enum<E>> extends EnumSet<E> {
- /**
- * Bit vector representation of this set. The ith bit of the jth
- * element of this array represents the presence of universe[64*j +i]
- * in this set.
- */
- private long elements[];
-
- // Redundant - maintained for performance
- private int size = 0;
-
- JumboEnumSet(Class<E>elementType, Enum[] universe) {
- super(elementType, universe);
- elements = new long[(universe.length + 63) >>> 6];
- }
-
- void addRange(E from, E to) {
- int fromIndex = from.ordinal() >>> 6;
- int toIndex = to.ordinal() >>> 6;
-
- if (fromIndex == toIndex) {
- elements[fromIndex] = (-1L >>> (from.ordinal() - to.ordinal() - 1))
- << from.ordinal();
- } else {
- elements[fromIndex] = (-1L << from.ordinal());
- for (int i = fromIndex + 1; i < toIndex; i++)
- elements[i] = -1;
- elements[toIndex] = -1L >>> (63 - to.ordinal());
- }
- size = to.ordinal() - from.ordinal() + 1;
- }
-
- void addAll() {
- for (int i = 0; i < elements.length; i++)
- elements[i] = -1;
- elements[elements.length - 1] >>>= -universe.length;
- size = universe.length;
- }
-
- void complement() {
- for (int i = 0; i < elements.length; i++)
- elements[i] = ~elements[i];
- elements[elements.length - 1] &= (-1L >>> -universe.length);
- size = universe.length - size;
- }
-
- /**
- * 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 "weakly consistent" iterator that will never throw {@link
- * ConcurrentModificationException}.
- *
- * @return an iterator over the elements contained in this set
- */
- public Iterator<E> iterator() {
- return new EnumSetIterator<E>();
- }
-
- private class EnumSetIterator<E extends Enum<E>> implements Iterator<E> {
- /**
- * A bit vector representing the elements in the current "word"
- * of the set not yet returned by this iterator.
- */
- long unseen;
-
- /**
- * The index corresponding to unseen in the elements array.
- */
- int unseenIndex = 0;
-
- /**
- * The bit representing the last element returned by this iterator
- * but not removed, or zero if no such element exists.
- */
- long lastReturned = 0;
-
- /**
- * The index corresponding to lastReturned in the elements array.
- */
- int lastReturnedIndex = 0;
-
- EnumSetIterator() {
- unseen = elements[0];
- }
-
- public boolean hasNext() {
- while (unseen == 0 && unseenIndex < elements.length - 1)
- unseen = elements[++unseenIndex];
- return unseen != 0;
- }
-
- public E next() {
- if (!hasNext())
- throw new NoSuchElementException();
- lastReturned = unseen & -unseen;
- lastReturnedIndex = unseenIndex;
- unseen -= lastReturned;
- return (E) universe[(lastReturnedIndex << 6)
- + Long.numberOfTrailingZeros(lastReturned)];
- }
-
- public void remove() {
- if (lastReturned == 0)
- throw new IllegalStateException();
- elements[lastReturnedIndex] -= lastReturned;
- size--;
- lastReturned = 0;
- }
- }
-
- /**
- * Returns the number of elements in this set.
- *
- * @return the number of elements in this set
- */
- public int size() {
- return size;
- }
-
- /**
- * Returns <tt>true</tt> if this set contains no elements.
- *
- * @return <tt>true</tt> if this set contains no elements
- */
- public boolean isEmpty() {
- return size == 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;
-
- int eOrdinal = ((Enum)e).ordinal();
- return (elements[eOrdinal >>> 6] & (1L << eOrdinal)) != 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);
-
- int eOrdinal = e.ordinal();
- int eWordNum = eOrdinal >>> 6;
-
- long oldElements = elements[eWordNum];
- elements[eWordNum] |= (1L << eOrdinal);
- boolean result = (elements[eWordNum] != oldElements);
- if (result)
- size++;
- return result;
- }
-
- /**
- * 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;
- int eOrdinal = ((Enum)e).ordinal();
- int eWordNum = eOrdinal >>> 6;
-
- long oldElements = elements[eWordNum];
- elements[eWordNum] &= ~(1L << eOrdinal);
- boolean result = (elements[eWordNum] != oldElements);
- if (result)
- size--;
- return result;
- }
-
- // 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 JumboEnumSet))
- return super.containsAll(c);
-
- JumboEnumSet es = (JumboEnumSet)c;
- if (es.elementType != elementType)
- return es.isEmpty();
-
- for (int i = 0; i < elements.length; i++)
- if ((es.elements[i] & ~elements[i]) != 0)
- return false;
- return true;
- }
-
- /**
- * 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 JumboEnumSet))
- return super.addAll(c);
-
- JumboEnumSet es = (JumboEnumSet)c;
- if (es.elementType != elementType) {
- if (es.isEmpty())
- return false;
- else
- throw new ClassCastException(
- es.elementType + " != " + elementType);
- }
-
- for (int i = 0; i < elements.length; i++)
- elements[i] |= es.elements[i];
- return recalculateSize();
- }
-
- /**
- * 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 JumboEnumSet))
- return super.removeAll(c);
-
- JumboEnumSet es = (JumboEnumSet)c;
- if (es.elementType != elementType)
- return false;
-
- for (int i = 0; i < elements.length; i++)
- elements[i] &= ~es.elements[i];
- return recalculateSize();
- }
-
- /**
- * 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 JumboEnumSet))
- return super.retainAll(c);
-
- JumboEnumSet es = (JumboEnumSet)c;
- if (es.elementType != elementType) {
- clear();
- return true;
- }
-
- for (int i = 0; i < elements.length; i++)
- elements[i] &= es.elements[i];
- return recalculateSize();
- }
-
- /**
- * Removes all of the elements from this set.
- */
- public void clear() {
- Arrays.fill(elements, 0);
- size = 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 e 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 JumboEnumSet))
- return super.equals(o);
-
- JumboEnumSet es = (JumboEnumSet)o;
- if (es.elementType != elementType)
- return size == 0 && es.size == 0;
-
- return Arrays.equals(es.elements, elements);
- }
-
- /**
- * Recalculates the size of the set. Returns true if it's changed.
- */
- private boolean recalculateSize() {
- int oldSize = size;
- size = 0;
- for (long elt : elements)
- size += Long.bitCount(elt);
-
- return size != oldSize;
- }
-
- public EnumSet<E> clone() {
- JumboEnumSet<E> result = (JumboEnumSet<E>) super.clone();
- result.elements = (long[]) result.elements.clone();
- return result;
- }
- }