diff -r 000000000000 -r 724f3e1ea53e emul/compact/src/main/java/java/util/TreeSet.java --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/emul/compact/src/main/java/java/util/TreeSet.java Sat Sep 07 13:51:24 2013 +0200 @@ -0,0 +1,539 @@ +/* + * Copyright (c) 1998, 2010, 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; + +/** + * A {@link NavigableSet} implementation based on a {@link TreeMap}. + * The elements are ordered using their {@linkplain Comparable natural + * ordering}, or by a {@link Comparator} provided at set creation + * time, depending on which constructor is used. + * + *

This implementation provides guaranteed log(n) time cost for the basic + * operations ({@code add}, {@code remove} and {@code contains}). + * + *

Note that the ordering maintained by a set (whether or not an explicit + * comparator is provided) must be consistent with equals if it is to + * correctly implement the {@code Set} interface. (See {@code Comparable} + * or {@code Comparator} for a precise definition of consistent with + * equals.) This is so because the {@code Set} interface is defined in + * terms of the {@code equals} operation, but a {@code TreeSet} instance + * performs all element comparisons using its {@code compareTo} (or + * {@code compare}) method, so two elements that are deemed equal by this method + * are, from the standpoint of the set, equal. The behavior of a set + * is well-defined even if its ordering is inconsistent with equals; it + * just fails to obey the general contract of the {@code Set} interface. + * + *

Note that this implementation is not synchronized. + * If multiple threads access a tree set concurrently, and at least one + * of the threads modifies the set, it must be synchronized + * externally. This is typically accomplished by synchronizing on some + * object that naturally encapsulates the set. + * If no such object exists, the set should be "wrapped" using the + * {@link Collections#synchronizedSortedSet Collections.synchronizedSortedSet} + * method. This is best done at creation time, to prevent accidental + * unsynchronized access to the set:

+ *   SortedSet s = Collections.synchronizedSortedSet(new TreeSet(...));
+ * + *

The iterators returned by this class's {@code iterator} method are + * fail-fast: if the set is modified at any time after the iterator is + * created, in any way except through the iterator's own {@code remove} + * method, the iterator will throw a {@link ConcurrentModificationException}. + * Thus, in the face of concurrent modification, the iterator fails quickly + * and cleanly, rather than risking arbitrary, non-deterministic behavior at + * an undetermined time in the future. + * + *

Note that the fail-fast behavior of an iterator cannot be guaranteed + * as it is, generally speaking, impossible to make any hard guarantees in the + * presence of unsynchronized concurrent modification. Fail-fast iterators + * throw {@code ConcurrentModificationException} on a best-effort basis. + * Therefore, it would be wrong to write a program that depended on this + * exception for its correctness: the fail-fast behavior of iterators + * should be used only to detect bugs. + * + *

This class is a member of the + * + * Java Collections Framework. + * + * @param the type of elements maintained by this set + * + * @author Josh Bloch + * @see Collection + * @see Set + * @see HashSet + * @see Comparable + * @see Comparator + * @see TreeMap + * @since 1.2 + */ + +public class TreeSet extends AbstractSet + implements NavigableSet, Cloneable, java.io.Serializable +{ + /** + * The backing map. + */ + private transient NavigableMap m; + + // Dummy value to associate with an Object in the backing Map + private static final Object PRESENT = new Object(); + + /** + * Constructs a set backed by the specified navigable map. + */ + TreeSet(NavigableMap m) { + this.m = m; + } + + /** + * Constructs a new, empty tree set, sorted according to the + * natural ordering of its elements. All elements inserted into + * the set must implement the {@link Comparable} interface. + * Furthermore, all such elements must be mutually + * comparable: {@code e1.compareTo(e2)} must not throw a + * {@code ClassCastException} for any elements {@code e1} and + * {@code e2} in the set. If the user attempts to add an element + * to the set that violates this constraint (for example, the user + * attempts to add a string element to a set whose elements are + * integers), the {@code add} call will throw a + * {@code ClassCastException}. + */ + public TreeSet() { + this(new TreeMap()); + } + + /** + * Constructs a new, empty tree set, sorted according to the specified + * comparator. All elements inserted into the set must be mutually + * comparable by the specified comparator: {@code comparator.compare(e1, + * e2)} must not throw a {@code ClassCastException} for any elements + * {@code e1} and {@code e2} in the set. If the user attempts to add + * an element to the set that violates this constraint, the + * {@code add} call will throw a {@code ClassCastException}. + * + * @param comparator the comparator that will be used to order this set. + * If {@code null}, the {@linkplain Comparable natural + * ordering} of the elements will be used. + */ + public TreeSet(Comparator comparator) { + this(new TreeMap<>(comparator)); + } + + /** + * Constructs a new tree set containing the elements in the specified + * collection, sorted according to the natural ordering of its + * elements. All elements inserted into the set must implement the + * {@link Comparable} interface. Furthermore, all such elements must be + * mutually comparable: {@code e1.compareTo(e2)} must not throw a + * {@code ClassCastException} for any elements {@code e1} and + * {@code e2} in the set. + * + * @param c collection whose elements will comprise the new set + * @throws ClassCastException if the elements in {@code c} are + * not {@link Comparable}, or are not mutually comparable + * @throws NullPointerException if the specified collection is null + */ + public TreeSet(Collection c) { + this(); + addAll(c); + } + + /** + * Constructs a new tree set containing the same elements and + * using the same ordering as the specified sorted set. + * + * @param s sorted set whose elements will comprise the new set + * @throws NullPointerException if the specified sorted set is null + */ + public TreeSet(SortedSet s) { + this(s.comparator()); + addAll(s); + } + + /** + * Returns an iterator over the elements in this set in ascending order. + * + * @return an iterator over the elements in this set in ascending order + */ + public Iterator iterator() { + return m.navigableKeySet().iterator(); + } + + /** + * Returns an iterator over the elements in this set in descending order. + * + * @return an iterator over the elements in this set in descending order + * @since 1.6 + */ + public Iterator descendingIterator() { + return m.descendingKeySet().iterator(); + } + + /** + * @since 1.6 + */ + public NavigableSet descendingSet() { + return new TreeSet<>(m.descendingMap()); + } + + /** + * Returns the number of elements in this set (its cardinality). + * + * @return the number of elements in this set (its cardinality) + */ + public int size() { + return m.size(); + } + + /** + * Returns {@code true} if this set contains no elements. + * + * @return {@code true} if this set contains no elements + */ + public boolean isEmpty() { + return m.isEmpty(); + } + + /** + * Returns {@code true} if this set contains the specified element. + * More formally, returns {@code true} if and only if this set + * contains an element {@code e} such that + * (o==null ? e==null : o.equals(e)). + * + * @param o object to be checked for containment in this set + * @return {@code true} if this set contains the specified element + * @throws ClassCastException if the specified object cannot be compared + * with the elements currently in the set + * @throws NullPointerException if the specified element is null + * and this set uses natural ordering, or its comparator + * does not permit null elements + */ + public boolean contains(Object o) { + return m.containsKey(o); + } + + /** + * Adds the specified element to this set if it is not already present. + * More formally, adds the specified element {@code e} to this set if + * the set contains no element {@code e2} such that + * (e==null ? e2==null : e.equals(e2)). + * If this set already contains the element, the call leaves the set + * unchanged and returns {@code false}. + * + * @param e element to be added to this set + * @return {@code true} if this set did not already contain the specified + * element + * @throws ClassCastException if the specified object cannot be compared + * with the elements currently in this set + * @throws NullPointerException if the specified element is null + * and this set uses natural ordering, or its comparator + * does not permit null elements + */ + public boolean add(E e) { + return m.put(e, PRESENT)==null; + } + + /** + * Removes the specified element from this set if it is present. + * More formally, removes an element {@code e} such that + * (o==null ? e==null : o.equals(e)), + * if this set contains such an element. Returns {@code true} if + * this set contained the element (or equivalently, if this set + * changed as a result of the call). (This set will not contain the + * element once the call returns.) + * + * @param o object to be removed from this set, if present + * @return {@code true} if this set contained the specified element + * @throws ClassCastException if the specified object cannot be compared + * with the elements currently in this set + * @throws NullPointerException if the specified element is null + * and this set uses natural ordering, or its comparator + * does not permit null elements + */ + public boolean remove(Object o) { + return m.remove(o)==PRESENT; + } + + /** + * Removes all of the elements from this set. + * The set will be empty after this call returns. + */ + public void clear() { + m.clear(); + } + + /** + * Adds all of the elements in the specified collection to this set. + * + * @param c collection containing elements to be added to this set + * @return {@code true} if this set changed as a result of the call + * @throws ClassCastException if the elements provided cannot be compared + * with the elements currently in the set + * @throws NullPointerException if the specified collection is null or + * if any element is null and this set uses natural ordering, or + * its comparator does not permit null elements + */ + public boolean addAll(Collection c) { + // Use linear-time version if applicable + if (m.size()==0 && c.size() > 0 && + c instanceof SortedSet && + m instanceof TreeMap) { + SortedSet set = (SortedSet) c; + TreeMap map = (TreeMap) m; + Comparator cc = (Comparator) set.comparator(); + Comparator mc = map.comparator(); + if (cc==mc || (cc != null && cc.equals(mc))) { + map.addAllForTreeSet(set, PRESENT); + return true; + } + } + return super.addAll(c); + } + + /** + * @throws ClassCastException {@inheritDoc} + * @throws NullPointerException if {@code fromElement} or {@code toElement} + * is null and this set uses natural ordering, or its comparator + * does not permit null elements + * @throws IllegalArgumentException {@inheritDoc} + * @since 1.6 + */ + public NavigableSet subSet(E fromElement, boolean fromInclusive, + E toElement, boolean toInclusive) { + return new TreeSet<>(m.subMap(fromElement, fromInclusive, + toElement, toInclusive)); + } + + /** + * @throws ClassCastException {@inheritDoc} + * @throws NullPointerException if {@code toElement} is null and + * this set uses natural ordering, or its comparator does + * not permit null elements + * @throws IllegalArgumentException {@inheritDoc} + * @since 1.6 + */ + public NavigableSet headSet(E toElement, boolean inclusive) { + return new TreeSet<>(m.headMap(toElement, inclusive)); + } + + /** + * @throws ClassCastException {@inheritDoc} + * @throws NullPointerException if {@code fromElement} is null and + * this set uses natural ordering, or its comparator does + * not permit null elements + * @throws IllegalArgumentException {@inheritDoc} + * @since 1.6 + */ + public NavigableSet tailSet(E fromElement, boolean inclusive) { + return new TreeSet<>(m.tailMap(fromElement, inclusive)); + } + + /** + * @throws ClassCastException {@inheritDoc} + * @throws NullPointerException if {@code fromElement} or + * {@code toElement} is null and this set uses natural ordering, + * or its comparator does not permit null elements + * @throws IllegalArgumentException {@inheritDoc} + */ + public SortedSet subSet(E fromElement, E toElement) { + return subSet(fromElement, true, toElement, false); + } + + /** + * @throws ClassCastException {@inheritDoc} + * @throws NullPointerException if {@code toElement} is null + * and this set uses natural ordering, or its comparator does + * not permit null elements + * @throws IllegalArgumentException {@inheritDoc} + */ + public SortedSet headSet(E toElement) { + return headSet(toElement, false); + } + + /** + * @throws ClassCastException {@inheritDoc} + * @throws NullPointerException if {@code fromElement} is null + * and this set uses natural ordering, or its comparator does + * not permit null elements + * @throws IllegalArgumentException {@inheritDoc} + */ + public SortedSet tailSet(E fromElement) { + return tailSet(fromElement, true); + } + + public Comparator comparator() { + return m.comparator(); + } + + /** + * @throws NoSuchElementException {@inheritDoc} + */ + public E first() { + return m.firstKey(); + } + + /** + * @throws NoSuchElementException {@inheritDoc} + */ + public E last() { + return m.lastKey(); + } + + // NavigableSet API methods + + /** + * @throws ClassCastException {@inheritDoc} + * @throws NullPointerException if the specified element is null + * and this set uses natural ordering, or its comparator + * does not permit null elements + * @since 1.6 + */ + public E lower(E e) { + return m.lowerKey(e); + } + + /** + * @throws ClassCastException {@inheritDoc} + * @throws NullPointerException if the specified element is null + * and this set uses natural ordering, or its comparator + * does not permit null elements + * @since 1.6 + */ + public E floor(E e) { + return m.floorKey(e); + } + + /** + * @throws ClassCastException {@inheritDoc} + * @throws NullPointerException if the specified element is null + * and this set uses natural ordering, or its comparator + * does not permit null elements + * @since 1.6 + */ + public E ceiling(E e) { + return m.ceilingKey(e); + } + + /** + * @throws ClassCastException {@inheritDoc} + * @throws NullPointerException if the specified element is null + * and this set uses natural ordering, or its comparator + * does not permit null elements + * @since 1.6 + */ + public E higher(E e) { + return m.higherKey(e); + } + + /** + * @since 1.6 + */ + public E pollFirst() { + Map.Entry e = m.pollFirstEntry(); + return (e == null) ? null : e.getKey(); + } + + /** + * @since 1.6 + */ + public E pollLast() { + Map.Entry e = m.pollLastEntry(); + return (e == null) ? null : e.getKey(); + } + + /** + * Returns a shallow copy of this {@code TreeSet} instance. (The elements + * themselves are not cloned.) + * + * @return a shallow copy of this set + */ + public Object clone() { + TreeSet clone = null; + try { + clone = (TreeSet) super.clone(); + } catch (CloneNotSupportedException e) { + throw new InternalError(); + } + + clone.m = new TreeMap<>(m); + return clone; + } + + /** + * Save the state of the {@code TreeSet} instance to a stream (that is, + * serialize it). + * + * @serialData Emits the comparator used to order this set, or + * {@code null} if it obeys its elements' natural ordering + * (Object), followed by the size of the set (the number of + * elements it contains) (int), followed by all of its + * elements (each an Object) in order (as determined by the + * set's Comparator, or by the elements' natural ordering if + * the set has no Comparator). + */ + private void writeObject(java.io.ObjectOutputStream s) + throws java.io.IOException { + // Write out any hidden stuff + s.defaultWriteObject(); + + // Write out Comparator + s.writeObject(m.comparator()); + + // Write out size + s.writeInt(m.size()); + + // Write out all elements in the proper order. + for (E e : m.keySet()) + s.writeObject(e); + } + + /** + * Reconstitute the {@code TreeSet} instance from a stream (that is, + * deserialize it). + */ + private void readObject(java.io.ObjectInputStream s) + throws java.io.IOException, ClassNotFoundException { + // Read in any hidden stuff + s.defaultReadObject(); + + // Read in Comparator + Comparator c = (Comparator) s.readObject(); + + // Create backing TreeMap + TreeMap tm; + if (c==null) + tm = new TreeMap<>(); + else + tm = new TreeMap<>(c); + m = tm; + + // Read in size + int size = s.readInt(); + + tm.readTreeSet(size, s, PRESENT); + } + + private static final long serialVersionUID = -2479143000061671589L; +}