/* * Copyright (c) 2003, 2011, 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 "jumbo" enum types * (i.e., those with more than 64 elements). * * @author Josh Bloch * @since 1.5 * @serial exclude */ class JumboEnumSet> extends EnumSet { private static final long serialVersionUID = 334349849919042784L; /** * 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(ClasselementType, 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 natural order (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 iterator() { return new EnumSetIterator<>(); } private class EnumSetIterator> implements Iterator { /** * 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(); final long oldElements = elements[lastReturnedIndex]; elements[lastReturnedIndex] &= ~lastReturned; if (oldElements != elements[lastReturnedIndex]) { 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 true if this set contains no elements. * * @return true if this set contains no elements */ public boolean isEmpty() { return size == 0; } /** * Returns true if this set contains the specified element. * * @param e element to be checked for containment in this collection * @return true 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 true if the set changed as a result of the call * * @throws NullPointerException if e 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 true 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 true if this set contains all of the elements * in the specified collection. * * @param c collection to be checked for containment in this set * @return true 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 true 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 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 true 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 true 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) { boolean changed = (size != 0); clear(); return changed; } 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 * true 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 true 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 clone() { JumboEnumSet result = (JumboEnumSet) super.clone(); result.elements = result.elements.clone(); return result; } }