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/* |
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* Written by Doug Lea with assistance from members of JCP JSR-166 |
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* Expert Group and released to the public domain, as explained at |
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* http://creativecommons.org/licenses/publicdomain |
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* http://creativecommons.org/publicdomain/zero/1.0/ |
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*/ |
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package jsr166x; |
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package jsr166x; |
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import java.util.*; |
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import java.util.concurrent.*; |
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* ascending order, sorted according to the <i>natural order</i> for |
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* the element's class (see {@link Comparable}), or by the comparator |
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* provided at creation time, depending on which constructor is |
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* used.<p> |
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* used. |
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* |
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* This implementation provides expected average <i>log(n)</i> time |
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* <p>This implementation provides expected average <i>log(n)</i> time |
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* cost for the <tt>contains</tt>, <tt>add</tt>, and <tt>remove</tt> |
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* operations and their variants. Insertion, removal, and access |
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* operations safely execute concurrently by multiple |
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* threads. Iterators are <i>weakly consistent</i>, returning elements |
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* reflecting the state of the set at some point at or since the |
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* creation of the iterator. They do <em>not</em> throw {@link |
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* ConcurrentModificationException}, and may procede concurrently with |
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* ConcurrentModificationException}, and may proceed concurrently with |
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* other operations. |
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* |
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* <p>Beware that, unlike in most collections, the <tt>size</tt> |
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* method is <em>NOT</em> a constant-time operation. Because of the |
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* method is <em>not</em> a constant-time operation. Because of the |
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* asynchronous nature of these sets, determining the current number |
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* of elements requires a traversal of the elements. |
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* of elements requires a traversal of the elements. Additionally, the |
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* bulk operations <tt>addAll</tt>, <tt>removeAll</tt>, |
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* <<tt>retainAll</tt>, and tt>containsAll</tt> are <em>not</em> |
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* guaranteed to be performed atomically. For example, an iterator |
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* operating concurrently with an <tt>addAll</tt> operation might view |
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* only some of the added elements. |
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* |
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* <p>This class and its iterators implement all of the |
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* <em>optional</em> methods of the {@link Set} and {@link Iterator} |
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* fields of underlying map, but enables this field to be declared |
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* final, which is necessary for thread safety. |
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*/ |
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private final ConcurrentSkipListMap<E,Object> m; |
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private final ConcurrentSkipListMap<E,Object> m; |
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/** |
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* Constructs a new, empty set, sorted according to the elements' natural |
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* order. |
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* order. |
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*/ |
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public ConcurrentSkipListSet() { |
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m = new ConcurrentSkipListMap<E,Object>(); |
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/** |
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* Constructs a new, empty set, sorted according to the specified |
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* comparator. |
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* comparator. |
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* |
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* @param c the comparator that will be used to sort this set. A |
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* <tt>null</tt> value indicates that the elements' <i>natural |
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* Constructs a new set containing the elements in the specified |
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* collection, sorted according to the elements' <i>natural order</i>. |
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* |
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* @param c The elements that will comprise the new set. |
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* @param c The elements that will comprise the new set |
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* |
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* @throws ClassCastException if the elements in the specified |
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* collection are not comparable, or are not mutually comparable. |
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* @throws NullPointerException if the specified collection is <tt>null</tt>. |
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* collection are not comparable, or are not mutually comparable |
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* @throws NullPointerException if the specified collection is |
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* <tt>null</tt> |
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*/ |
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public ConcurrentSkipListSet(Collection<? extends E> c) { |
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m = new ConcurrentSkipListMap<E,Object>(); |
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* Constructs a new set containing the same elements as the specified |
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* sorted set, sorted according to the same ordering. |
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* |
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* @param s sorted set whose elements will comprise the new set. |
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* @throws NullPointerException if the specified sorted set is <tt>null</tt>. |
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* @param s sorted set whose elements will comprise the new set |
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* @throws NullPointerException if the specified sorted set is |
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* <tt>null</tt> |
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*/ |
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public ConcurrentSkipListSet(SortedSet<E> s) { |
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m = new ConcurrentSkipListMap<E,Object>(s.comparator()); |
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* Returns a shallow copy of this set. (The elements themselves |
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* are not cloned.) |
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* |
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* @return a shallow copy of this set. |
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* @return a shallow copy of this set |
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*/ |
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public Object clone() { |
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ConcurrentSkipListSet<E> clone = null; |
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try { |
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clone = (ConcurrentSkipListSet<E>) super.clone(); |
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} catch (CloneNotSupportedException e) { |
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throw new InternalError(); |
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} |
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try { |
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clone = (ConcurrentSkipListSet<E>) super.clone(); |
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} catch (CloneNotSupportedException e) { |
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throw new InternalError(); |
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} |
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clone.m.initialize(); |
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clone.addAll(this); |
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* will be inaccurate. Thus, this method is typically not very |
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* useful in concurrent applications. |
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* |
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* @return the number of elements in this set. |
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* @return the number of elements in this set |
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*/ |
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public int size() { |
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return m.size(); |
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return m.size(); |
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} |
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/** |
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* Returns <tt>true</tt> if this set contains no elements. |
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* @return <tt>true</tt> if this set contains no elements. |
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* @return <tt>true</tt> if this set contains no elements |
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*/ |
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public boolean isEmpty() { |
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return m.isEmpty(); |
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return m.isEmpty(); |
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} |
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/** |
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* Returns <tt>true</tt> if this set contains the specified element. |
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* |
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* @param o the object to be checked for containment in this set. |
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* @return <tt>true</tt> if this set contains the specified element. |
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* @param o the object to be checked for containment in this set |
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* @return <tt>true</tt> if this set contains the specified element |
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* |
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* @throws ClassCastException if the specified object cannot be compared |
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* with the elements currently in the set. |
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* @throws NullPointerException if o is <tt>null</tt>. |
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* with the elements currently in the set |
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* @throws NullPointerException if o is <tt>null</tt> |
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*/ |
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public boolean contains(Object o) { |
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return m.containsKey(o); |
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return m.containsKey(o); |
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} |
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/** |
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* Adds the specified element to this set if it is not already present. |
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* |
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* @param o element to be added to this set. |
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* @param o element to be added to this set |
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* @return <tt>true</tt> if the set did not already contain the specified |
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* element. |
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* element |
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* |
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* @throws ClassCastException if the specified object cannot be compared |
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* with the elements currently in the set. |
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* @throws NullPointerException if o is <tt>null</tt>. |
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* with the elements currently in the set |
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* @throws NullPointerException if o is <tt>null</tt> |
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*/ |
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public boolean add(E o) { |
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return m.putIfAbsent(o, Boolean.TRUE) == null; |
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return m.putIfAbsent(o, Boolean.TRUE) == null; |
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} |
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/** |
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* Removes the specified element from this set if it is present. |
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* |
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* @param o object to be removed from this set, if present. |
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* @return <tt>true</tt> if the set contained the specified element. |
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* @param o object to be removed from this set, if present |
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* @return <tt>true</tt> if the set contained the specified element |
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* |
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* @throws ClassCastException if the specified object cannot be compared |
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* with the elements currently in the set. |
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* @throws NullPointerException if o is <tt>null</tt>. |
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* with the elements currently in the set |
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* @throws NullPointerException if o is <tt>null</tt> |
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*/ |
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public boolean remove(Object o) { |
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return m.removep(o); |
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return m.removep(o); |
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} |
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/** |
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* Removes all of the elements from this set. |
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*/ |
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public void clear() { |
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m.clear(); |
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m.clear(); |
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} |
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/** |
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* Returns an iterator over the elements in this set. The elements |
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* are returned in ascending order. |
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* |
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* @return an iterator over the elements in this set. |
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* @return an iterator over the elements in this set |
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*/ |
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public Iterator<E> iterator() { |
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return m.keyIterator(); |
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return m.keyIterator(); |
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} |
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|
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/** |
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* Returns an iterator over the elements in this set. The elements |
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* are returned in descending order. |
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* |
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* @return an iterator over the elements in this set |
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*/ |
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public Iterator<E> descendingIterator() { |
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return m.descendingKeyIterator(); |
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} |
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|
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/* ---------------- AbstractSet Overrides -------------- */ |
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|
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/** |
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* Compares the specified object with this set for equality. Returns |
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* <tt>true</tt> if the specified object is also a set, the two sets |
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* have the same size, and every member of the specified set is |
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* contained in this set (or equivalently, every member of this set is |
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* contained in the specified set). This definition ensures that the |
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* equals method works properly across different implementations of the |
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* set interface. |
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* |
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* @param o Object to be compared for equality with this set |
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* @return <tt>true</tt> if the specified Object is equal to this set |
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*/ |
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public boolean equals(Object o) { |
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// Override AbstractSet version to avoid calling size() |
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if (o == this) |
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return true; |
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if (!(o instanceof Set)) |
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return false; |
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Collection c = (Collection) o; |
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try { |
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return containsAll(c) && c.containsAll(this); |
256 |
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} catch (ClassCastException unused) { |
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return false; |
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} catch (NullPointerException unused) { |
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return false; |
260 |
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} |
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} |
262 |
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|
263 |
> |
/** |
264 |
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* Removes from this set all of its elements that are contained in |
265 |
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* the specified collection. If the specified collection is also |
266 |
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* a set, this operation effectively modifies this set so that its |
267 |
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* value is the <i>asymmetric set difference</i> of the two sets. |
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* |
269 |
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* @param c collection that defines which elements will be removed from |
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* this set |
271 |
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* @return <tt>true</tt> if this set changed as a result of the call |
272 |
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* |
273 |
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* @throws ClassCastException if the types of one or more elements in this |
274 |
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* set are incompatible with the specified collection |
275 |
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* @throws NullPointerException if the specified collection, or any |
276 |
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* of its elements are <tt>null</tt> |
277 |
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*/ |
278 |
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public boolean removeAll(Collection<?> c) { |
279 |
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// Override AbstractSet version to avoid unnecessary call to size() |
280 |
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boolean modified = false; |
281 |
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for (Iterator<?> i = c.iterator(); i.hasNext(); ) |
282 |
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if (remove(i.next())) |
283 |
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modified = true; |
284 |
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return modified; |
285 |
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} |
286 |
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|
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/* ---------------- Relational operations -------------- */ |
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/** |
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* Returns an element greater than or equal to the given element, or |
291 |
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* <tt>null</tt> if there is no such element. |
292 |
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* |
292 |
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* |
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* @param o the value to match |
294 |
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* @return an element greater than or equal to given element, or <tt>null</tt> |
295 |
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* if there is no such element. |
294 |
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* @return an element greater than or equal to given element, or |
295 |
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* <tt>null</tt> if there is no such element |
296 |
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* @throws ClassCastException if o cannot be compared with the elements |
297 |
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* currently in the set. |
297 |
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* currently in the set |
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* @throws NullPointerException if o is <tt>null</tt> |
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*/ |
300 |
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public E ceiling(E o) { |
302 |
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} |
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|
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/** |
305 |
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* Returns an element strictly less than the given element, or <tt>null</tt> if |
306 |
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* there is no such element. |
307 |
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* |
305 |
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* Returns an element strictly less than the given element, or |
306 |
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* <tt>null</tt> if there is no such element. |
307 |
> |
* |
308 |
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* @param o the value to match |
309 |
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* @return the greatest element less than the given element, or |
310 |
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* <tt>null</tt> if there is no such element. |
310 |
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* <tt>null</tt> if there is no such element |
311 |
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* @throws ClassCastException if o cannot be compared with the elements |
312 |
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* currently in the set. |
313 |
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* @throws NullPointerException if o is <tt>null</tt>. |
312 |
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* currently in the set |
313 |
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* @throws NullPointerException if o is <tt>null</tt> |
314 |
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*/ |
315 |
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public E lower(E o) { |
316 |
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return m.lowerKey(o); |
317 |
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} |
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|
319 |
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/** |
320 |
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* Returns an element less than or equal to the given element, or <tt>null</tt> |
321 |
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* if there is no such element. |
322 |
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* |
320 |
> |
* Returns an element less than or equal to the given element, or |
321 |
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* <tt>null</tt> if there is no such element. |
322 |
> |
* |
323 |
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* @param o the value to match |
324 |
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* @return the greatest element less than or equal to given |
325 |
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* element, or <tt>null</tt> if there is no such element. |
325 |
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* element, or <tt>null</tt> if there is no such element |
326 |
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* @throws ClassCastException if o cannot be compared with the elements |
327 |
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* currently in the set. |
328 |
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* @throws NullPointerException if o is <tt>null</tt>. |
327 |
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* currently in the set |
328 |
> |
* @throws NullPointerException if o is <tt>null</tt> |
329 |
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*/ |
330 |
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public E floor(E o) { |
331 |
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return m.floorKey(o); |
332 |
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} |
333 |
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|
334 |
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/** |
335 |
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* Returns an element strictly greater than the given element, or <tt>null</tt> |
336 |
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* if there is no such element. |
337 |
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* |
335 |
> |
* Returns an element strictly greater than the given element, or |
336 |
> |
* <tt>null</tt> if there is no such element. |
337 |
> |
* |
338 |
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* @param o the value to match |
339 |
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* @return the least element greater than the given element, or |
340 |
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* <tt>null</tt> if there is no such element. |
340 |
> |
* <tt>null</tt> if there is no such element |
341 |
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* @throws ClassCastException if o cannot be compared with the elements |
342 |
< |
* currently in the set. |
343 |
< |
* @throws NullPointerException if o is <tt>null</tt>. |
342 |
> |
* currently in the set |
343 |
> |
* @throws NullPointerException if o is <tt>null</tt> |
344 |
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*/ |
345 |
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public E higher(E o) { |
346 |
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return m.higherKey(o); |
349 |
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/** |
350 |
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* Retrieves and removes the first (lowest) element. |
351 |
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* |
352 |
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* @return the least element, or <tt>null</tt> if empty. |
352 |
> |
* @return the least element, or <tt>null</tt> if empty |
353 |
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*/ |
354 |
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public E pollFirst() { |
355 |
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return m.removeFirstKey(); |
355 |
> |
return m.pollFirstKey(); |
356 |
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} |
357 |
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|
358 |
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/** |
359 |
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* Retrieves and removes the last (highest) element. |
360 |
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* |
361 |
< |
* @return the last element, or <tt>null</tt> if empty. |
361 |
> |
* @return the last element, or <tt>null</tt> if empty |
362 |
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*/ |
363 |
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public E pollLast() { |
364 |
< |
return m.removeLastKey(); |
364 |
> |
return m.pollLastKey(); |
365 |
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} |
366 |
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|
367 |
|
|
373 |
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* if this set uses its elements natural ordering. |
374 |
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* |
375 |
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* @return the comparator used to order this set, or <tt>null</tt> |
376 |
< |
* if this set uses its elements natural ordering. |
376 |
> |
* if this set uses its elements natural ordering |
377 |
|
*/ |
378 |
|
public Comparator<? super E> comparator() { |
379 |
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return m.comparator(); |
382 |
|
/** |
383 |
|
* Returns the first (lowest) element currently in this set. |
384 |
|
* |
385 |
< |
* @return the first (lowest) element currently in this set. |
386 |
< |
* @throws NoSuchElementException sorted set is empty. |
385 |
> |
* @return the first (lowest) element currently in this set |
386 |
> |
* @throws NoSuchElementException sorted set is empty |
387 |
|
*/ |
388 |
|
public E first() { |
389 |
|
return m.firstKey(); |
392 |
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/** |
393 |
|
* Returns the last (highest) element currently in this set. |
394 |
|
* |
395 |
< |
* @return the last (highest) element currently in this set. |
396 |
< |
* @throws NoSuchElementException sorted set is empty. |
395 |
> |
* @return the last (highest) element currently in this set |
396 |
> |
* @throws NoSuchElementException sorted set is empty |
397 |
|
*/ |
398 |
|
public E last() { |
399 |
|
return m.lastKey(); |
400 |
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} |
401 |
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|
402 |
+ |
|
403 |
+ |
|
404 |
|
/** |
405 |
|
* Returns a view of the portion of this set whose elements range from |
406 |
|
* <tt>fromElement</tt>, inclusive, to <tt>toElement</tt>, exclusive. (If |
407 |
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* <tt>fromElement</tt> and <tt>toElement</tt> are equal, the returned |
408 |
|
* sorted set is empty.) The returned sorted set is backed by this set, |
409 |
|
* so changes in the returned sorted set are reflected in this set, and |
410 |
< |
* vice-versa. |
411 |
< |
* @param fromElement low endpoint (inclusive) of the subSet. |
412 |
< |
* @param toElement high endpoint (exclusive) of the subSet. |
410 |
> |
* vice-versa. |
411 |
> |
* @param fromElement low endpoint (inclusive) of the subSet |
412 |
> |
* @param toElement high endpoint (exclusive) of the subSet |
413 |
|
* @return a view of the portion of this set whose elements range from |
414 |
< |
* <tt>fromElement</tt>, inclusive, to <tt>toElement</tt>, |
415 |
< |
* exclusive. |
414 |
> |
* <tt>fromElement</tt>, inclusive, to <tt>toElement</tt>, |
415 |
> |
* exclusive |
416 |
|
* @throws ClassCastException if <tt>fromElement</tt> and |
417 |
|
* <tt>toElement</tt> cannot be compared to one another using |
418 |
|
* this set's comparator (or, if the set has no comparator, |
419 |
< |
* using natural ordering). |
419 |
> |
* using natural ordering) |
420 |
|
* @throws IllegalArgumentException if <tt>fromElement</tt> is |
421 |
< |
* greater than <tt>toElement</tt>. |
421 |
> |
* greater than <tt>toElement</tt> |
422 |
|
* @throws NullPointerException if <tt>fromElement</tt> or |
423 |
< |
* <tt>toElement</tt> is <tt>null</tt>. |
423 |
> |
* <tt>toElement</tt> is <tt>null</tt> |
424 |
|
*/ |
425 |
|
public NavigableSet<E> subSet(E fromElement, E toElement) { |
426 |
< |
return new ConcurrentSkipListSubSet<E>(m, fromElement, toElement); |
426 |
> |
return new ConcurrentSkipListSubSet<E>(m, fromElement, toElement); |
427 |
|
} |
428 |
|
|
429 |
|
/** |
430 |
|
* Returns a view of the portion of this set whose elements are strictly |
431 |
|
* less than <tt>toElement</tt>. The returned sorted set is backed by |
432 |
|
* this set, so changes in the returned sorted set are reflected in this |
433 |
< |
* set, and vice-versa. |
434 |
< |
* @param toElement high endpoint (exclusive) of the headSet. |
433 |
> |
* set, and vice-versa. |
434 |
> |
* @param toElement high endpoint (exclusive) of the headSet |
435 |
|
* @return a view of the portion of this set whose elements are strictly |
436 |
< |
* less than toElement. |
436 |
> |
* less than toElement |
437 |
|
* @throws ClassCastException if <tt>toElement</tt> is not compatible |
438 |
|
* with this set's comparator (or, if the set has no comparator, |
439 |
< |
* if <tt>toElement</tt> does not implement <tt>Comparable</tt>). |
440 |
< |
* @throws NullPointerException if <tt>toElement</tt> is <tt>null</tt>. |
439 |
> |
* if <tt>toElement</tt> does not implement <tt>Comparable</tt>) |
440 |
> |
* @throws NullPointerException if <tt>toElement</tt> is <tt>null</tt> |
441 |
|
*/ |
442 |
|
public NavigableSet<E> headSet(E toElement) { |
443 |
< |
return new ConcurrentSkipListSubSet<E>(m, null, toElement); |
443 |
> |
return new ConcurrentSkipListSubSet<E>(m, null, toElement); |
444 |
|
} |
445 |
|
|
446 |
|
|
449 |
|
* greater than or equal to <tt>fromElement</tt>. The returned |
450 |
|
* sorted set is backed by this set, so changes in the returned |
451 |
|
* sorted set are reflected in this set, and vice-versa. |
452 |
< |
* @param fromElement low endpoint (inclusive) of the tailSet. |
452 |
> |
* @param fromElement low endpoint (inclusive) of the tailSet |
453 |
|
* @return a view of the portion of this set whose elements are |
454 |
< |
* greater than or equal to <tt>fromElement</tt>. |
454 |
> |
* greater than or equal to <tt>fromElement</tt> |
455 |
|
* @throws ClassCastException if <tt>fromElement</tt> is not |
456 |
|
* compatible with this set's comparator (or, if the set has no |
457 |
|
* comparator, if <tt>fromElement</tt> does not implement |
458 |
< |
* <tt>Comparable</tt>). |
459 |
< |
* @throws NullPointerException if <tt>fromElement</tt> is <tt>null</tt>. |
458 |
> |
* <tt>Comparable</tt>) |
459 |
> |
* @throws NullPointerException if <tt>fromElement</tt> is <tt>null</tt> |
460 |
|
*/ |
461 |
|
public NavigableSet<E> tailSet(E fromElement) { |
462 |
< |
return new ConcurrentSkipListSubSet<E>(m, fromElement, null); |
462 |
> |
return new ConcurrentSkipListSubSet<E>(m, fromElement, null); |
463 |
|
} |
464 |
|
|
465 |
|
/** |
471 |
|
* in {@link IllegalArgumentException}. Instances of this class are |
472 |
|
* constructed only using the <tt>subSet</tt>, <tt>headSet</tt>, and |
473 |
|
* <tt>tailSet</tt> methods of their underlying sets. |
401 |
– |
* |
474 |
|
*/ |
475 |
< |
static class ConcurrentSkipListSubSet<E> |
476 |
< |
extends AbstractSet<E> |
475 |
> |
static class ConcurrentSkipListSubSet<E> |
476 |
> |
extends AbstractSet<E> |
477 |
|
implements NavigableSet<E>, java.io.Serializable { |
478 |
|
|
479 |
|
private static final long serialVersionUID = -7647078645896651609L; |
480 |
|
|
481 |
< |
/** The underlying submap */ |
481 |
> |
/** The underlying submap */ |
482 |
|
private final ConcurrentSkipListMap.ConcurrentSkipListSubMap<E,Object> s; |
483 |
< |
|
483 |
> |
|
484 |
|
/** |
485 |
< |
* Creates a new submap. |
485 |
> |
* Creates a new submap. |
486 |
|
* @param fromElement inclusive least value, or <tt>null</tt> if from start |
487 |
|
* @param toElement exclusive upper bound or <tt>null</tt> if to end |
488 |
|
* @throws IllegalArgumentException if fromElement and toElement |
489 |
< |
* nonnull and fromElement greater than toElement |
489 |
> |
* non-null and fromElement greater than toElement |
490 |
|
*/ |
491 |
< |
ConcurrentSkipListSubSet(ConcurrentSkipListMap<E,Object> map, |
491 |
> |
ConcurrentSkipListSubSet(ConcurrentSkipListMap<E,Object> map, |
492 |
|
E fromElement, E toElement) { |
493 |
< |
s = new ConcurrentSkipListMap.ConcurrentSkipListSubMap<E,Object>(map, fromElement, |
494 |
< |
toElement); |
423 |
< |
} |
424 |
< |
|
425 |
< |
/** |
426 |
< |
* Returns the number of elements in this set. If this set |
427 |
< |
* contains more than <tt>Integer.MAX_VALUE</tt> elements, it |
428 |
< |
* returns <tt>Integer.MAX_VALUE</tt>. |
429 |
< |
* |
430 |
< |
* <p>Beware that, unlike in most collections, this method is |
431 |
< |
* <em>NOT</em> a constant-time operation. Because of the |
432 |
< |
* asynchronous nature of these sets, determining the current |
433 |
< |
* number of elements requires traversing them all to count them. |
434 |
< |
* Additionally, it is possible for the size to change during |
435 |
< |
* execution of this method, in which case the returned result |
436 |
< |
* will be inaccurate. Thus, this method is typically not very |
437 |
< |
* useful in concurrent applications. |
438 |
< |
* |
439 |
< |
* @return the number of elements in this set. |
440 |
< |
*/ |
441 |
< |
public int size() { |
442 |
< |
return s.size(); |
443 |
< |
} |
444 |
< |
|
445 |
< |
/** |
446 |
< |
* Returns <tt>true</tt> if this set contains no elements. |
447 |
< |
* @return <tt>true</tt> if this set contains no elements. |
448 |
< |
*/ |
449 |
< |
public boolean isEmpty() { |
450 |
< |
return s.isEmpty(); |
451 |
< |
} |
452 |
< |
|
453 |
< |
/** |
454 |
< |
* Returns <tt>true</tt> if this set contains the specified |
455 |
< |
* element. |
456 |
< |
* |
457 |
< |
* @param o the object to be checked for containment in this |
458 |
< |
* set. |
459 |
< |
* @return <tt>true</tt> if this set contains the specified |
460 |
< |
* element. |
461 |
< |
* |
462 |
< |
* @throws ClassCastException if the specified object cannot |
463 |
< |
* be compared with the elements currently in the set. |
464 |
< |
* @throws NullPointerException if o is <tt>null</tt>. |
465 |
< |
*/ |
466 |
< |
public boolean contains(Object o) { |
467 |
< |
return s.containsKey(o); |
493 |
> |
s = new ConcurrentSkipListMap.ConcurrentSkipListSubMap<E,Object> |
494 |
> |
(map, fromElement, toElement); |
495 |
|
} |
496 |
|
|
497 |
+ |
// subsubset construction |
498 |
|
|
499 |
< |
/** |
472 |
< |
* Adds the specified element to this set if it is not already |
473 |
< |
* present. |
474 |
< |
* |
475 |
< |
* @param o element to be added to this set. |
476 |
< |
* @return <tt>true</tt> if the set did not already contain |
477 |
< |
* the specified element. |
478 |
< |
* |
479 |
< |
* @throws ClassCastException if the specified object cannot |
480 |
< |
* be compared with the elements currently in the set. |
481 |
< |
* @throws IllegalArgumentException if o is outside the range |
482 |
< |
* of this subset. |
483 |
< |
* @throws NullPointerException if o is <tt>null</tt>. |
484 |
< |
*/ |
485 |
< |
public boolean add(E o) { |
486 |
< |
return s.put(o, Boolean.TRUE) == null; |
487 |
< |
} |
488 |
< |
|
489 |
< |
/** |
490 |
< |
* Removes the specified element from this set if it is |
491 |
< |
* present. |
492 |
< |
* |
493 |
< |
* @param o object to be removed from this set, if present. |
494 |
< |
* @return <tt>true</tt> if the set contained the specified element. |
495 |
< |
* |
496 |
< |
* @throws ClassCastException if the specified object cannot |
497 |
< |
* be compared with the elements currently in the set. |
498 |
< |
* @throws NullPointerException if o is <tt>null</tt>. |
499 |
< |
*/ |
500 |
< |
public boolean remove(Object o) { |
501 |
< |
return s.remove(o) != null; |
502 |
< |
} |
503 |
< |
|
504 |
< |
/** |
505 |
< |
* Removes all of the elements from this set. |
506 |
< |
*/ |
507 |
< |
public void clear() { |
508 |
< |
s.clear(); |
509 |
< |
} |
510 |
< |
|
511 |
< |
/** |
512 |
< |
* Returns an iterator over the elements in this set. The elements |
513 |
< |
* are returned in ascending order. |
514 |
< |
* |
515 |
< |
* @return an iterator over the elements in this set. |
516 |
< |
*/ |
517 |
< |
public Iterator<E> iterator() { |
518 |
< |
return s.keySet().iterator(); |
519 |
< |
} |
520 |
< |
|
521 |
< |
/** |
522 |
< |
* Returns an element greater than or equal to the given |
523 |
< |
* element, or <tt>null</tt> if there is no such element. |
524 |
< |
* |
525 |
< |
* @param o the value to match |
526 |
< |
* @return an element greater than or equal to given element, or <tt>null</tt> |
527 |
< |
* if there is no such element. |
528 |
< |
* @throws ClassCastException if o cannot be compared with the |
529 |
< |
* elements currently in the set. |
530 |
< |
* @throws NullPointerException if o is <tt>null</tt> |
531 |
< |
*/ |
532 |
< |
public E ceiling(E o) { |
533 |
< |
E key = o; |
534 |
< |
E least = s.getLeast(); |
535 |
< |
if (least != null && s.getMap().compare(o, least) < 0) |
536 |
< |
key = least; |
537 |
< |
E k = s.getMap().ceilingKey(key); |
538 |
< |
return (k != null && s.inHalfOpenRange(k))? k : null; |
539 |
< |
} |
540 |
< |
|
541 |
< |
/** |
542 |
< |
* Returns an element strictly less than the given element, or <tt>null</tt> if |
543 |
< |
* there is no such element. |
544 |
< |
* |
545 |
< |
* @param o the value to match |
546 |
< |
* @return the greatest element less than the given element, or |
547 |
< |
* <tt>null</tt> if there is no such element. |
548 |
< |
* @throws ClassCastException if o cannot be compared with the |
549 |
< |
* elements currently in the set. |
550 |
< |
* @throws NullPointerException if o is <tt>null</tt>. |
551 |
< |
*/ |
552 |
< |
public E lower(E o) { |
553 |
< |
E k = s.getMap().lowerKey(o); |
554 |
< |
return (k != null && s.inHalfOpenRange(k))? k : null; |
555 |
< |
} |
556 |
< |
|
557 |
< |
/** |
558 |
< |
* Returns an element less than or equal to the given element, or <tt>null</tt> |
559 |
< |
* if there is no such element. |
560 |
< |
* |
561 |
< |
* @param o the value to match |
562 |
< |
* @return the greatest element less than or equal to given |
563 |
< |
* element, or <tt>null</tt> if there is no such element. |
564 |
< |
* @throws ClassCastException if o cannot be compared with the |
565 |
< |
* elements currently in the set. |
566 |
< |
* @throws NullPointerException if o is <tt>null</tt>. |
567 |
< |
*/ |
568 |
< |
public E floor(E o) { |
569 |
< |
E k = s.getMap().floorKey(o); |
570 |
< |
return (k != null && s.inHalfOpenRange(k))? k : null; |
571 |
< |
} |
572 |
< |
|
573 |
< |
/** |
574 |
< |
* Returns an element strictly greater than the given element, or <tt>null</tt> |
575 |
< |
* if there is no such element. |
576 |
< |
* |
577 |
< |
* @param o the value to match |
578 |
< |
* @return the least element greater than the given element, or |
579 |
< |
* <tt>null</tt> if there is no such element. |
580 |
< |
* @throws ClassCastException if o cannot be compared with the |
581 |
< |
* elements currently in the set. |
582 |
< |
* @throws NullPointerException if o is <tt>null</tt>. |
583 |
< |
*/ |
584 |
< |
public E higher(E o) { |
585 |
< |
E k; |
586 |
< |
E least = s.getLeast(); |
587 |
< |
if (least != null && s.getMap().compare(o, least) < 0) |
588 |
< |
k = s.getMap().ceilingKey(least); |
589 |
< |
else |
590 |
< |
k = s.getMap().higherKey(o); |
591 |
< |
return (k != null && s.inHalfOpenRange(k))? k : null; |
592 |
< |
} |
593 |
< |
|
594 |
< |
/** |
595 |
< |
* Retrieves and removes the first (lowest) element. |
596 |
< |
* |
597 |
< |
* @return the first element, or <tt>null</tt> if empty. |
598 |
< |
*/ |
599 |
< |
public E pollFirst() { |
600 |
< |
for (;;) { |
601 |
< |
E k = s.lowestKey(); |
602 |
< |
if (k == null) |
603 |
< |
return null; |
604 |
< |
if (remove(k)) |
605 |
< |
return k; |
606 |
< |
} |
607 |
< |
} |
608 |
< |
|
609 |
< |
/** |
610 |
< |
* Retrieves and removes the last (highest) element. |
611 |
< |
* |
612 |
< |
* @return the last element, or <tt>null</tt> if empty. |
613 |
< |
*/ |
614 |
< |
public E pollLast() { |
615 |
< |
for (;;) { |
616 |
< |
E k = s.highestKey(); |
617 |
< |
if (k == null) |
618 |
< |
return null; |
619 |
< |
if (remove(k)) |
620 |
< |
return k; |
621 |
< |
} |
622 |
< |
} |
623 |
< |
|
624 |
< |
/** |
625 |
< |
* Returns the comparator used to order this set, or <tt>null</tt> |
626 |
< |
* if this set uses its elements natural ordering. |
627 |
< |
* |
628 |
< |
* @return the comparator used to order this set, or <tt>null</tt> |
629 |
< |
* if this set uses its elements natural ordering. |
630 |
< |
*/ |
631 |
< |
public Comparator<? super E> comparator() { |
632 |
< |
return s.comparator(); |
633 |
< |
} |
634 |
< |
|
635 |
< |
/** |
636 |
< |
* Returns the first (lowest) element currently in this set. |
637 |
< |
* |
638 |
< |
* @return the first (lowest) element currently in this set. |
639 |
< |
* @throws NoSuchElementException sorted set is empty. |
640 |
< |
*/ |
641 |
< |
public E first() { |
642 |
< |
return s.firstKey(); |
643 |
< |
} |
644 |
< |
|
645 |
< |
/** |
646 |
< |
* Returns the last (highest) element currently in this set. |
647 |
< |
* |
648 |
< |
* @return the last (highest) element currently in this set. |
649 |
< |
* @throws NoSuchElementException sorted set is empty. |
650 |
< |
*/ |
651 |
< |
public E last() { |
652 |
< |
return s.lastKey(); |
653 |
< |
} |
654 |
< |
|
655 |
< |
/** |
656 |
< |
* Returns a view of the portion of this set whose elements |
657 |
< |
* range from <tt>fromElement</tt>, inclusive, to |
658 |
< |
* <tt>toElement</tt>, exclusive. (If <tt>fromElement</tt> |
659 |
< |
* and <tt>toElement</tt> are equal, the returned sorted set |
660 |
< |
* is empty.) The returned sorted set is backed by this set, |
661 |
< |
* so changes in the returned sorted set are reflected in this |
662 |
< |
* set, and vice-versa. |
663 |
< |
* @param fromElement low endpoint (inclusive) of the subSet. |
664 |
< |
* @param toElement high endpoint (exclusive) of the subSet. |
665 |
< |
* @return a view of the portion of this set whose elements |
666 |
< |
* range from <tt>fromElement</tt>, inclusive, to |
667 |
< |
* <tt>toElement</tt>, exclusive. |
668 |
< |
* @throws ClassCastException if <tt>fromElement</tt> and |
669 |
< |
* <tt>toElement</tt> cannot be compared to one another using |
670 |
< |
* this set's comparator (or, if the set has no comparator, |
671 |
< |
* using natural ordering). |
672 |
< |
* @throws IllegalArgumentException if <tt>fromElement</tt> is |
673 |
< |
* greater than <tt>toElement</tt> or either key is outside |
674 |
< |
* the range of this set. |
675 |
< |
* @throws NullPointerException if <tt>fromElement</tt> or |
676 |
< |
* <tt>toElement</tt> is <tt>null</tt>. |
677 |
< |
*/ |
678 |
< |
public NavigableSet<E> subSet(E fromElement, |
679 |
< |
E toElement) { |
499 |
> |
public NavigableSet<E> subSet(E fromElement, E toElement) { |
500 |
|
if (!s.inOpenRange(fromElement) || !s.inOpenRange(toElement)) |
501 |
|
throw new IllegalArgumentException("element out of range"); |
502 |
< |
return new ConcurrentSkipListSubSet<E>(s.getMap(), |
502 |
> |
return new ConcurrentSkipListSubSet<E>(s.getMap(), |
503 |
|
fromElement, toElement); |
504 |
|
} |
505 |
|
|
686 |
– |
/** |
687 |
– |
* Returns a view of the portion of this set whose elements are |
688 |
– |
* strictly less than <tt>toElement</tt>. The returned sorted set |
689 |
– |
* is backed by this set, so changes in the returned sorted set |
690 |
– |
* are reflected in this set, and vice-versa. |
691 |
– |
* @param toElement high endpoint (exclusive) of the headSet. |
692 |
– |
* @return a view of the portion of this set whose elements |
693 |
– |
* are strictly less than toElement. |
694 |
– |
* @throws ClassCastException if <tt>toElement</tt> is not |
695 |
– |
* compatible with this set's comparator (or, if the set has |
696 |
– |
* no comparator, if <tt>toElement</tt> does not implement |
697 |
– |
* <tt>Comparable</tt>). |
698 |
– |
* @throws IllegalArgumentException if <tt>toElement</tt> is |
699 |
– |
* outside the range of this set. |
700 |
– |
* @throws NullPointerException if <tt>toElement</tt> is |
701 |
– |
* <tt>null</tt>. |
702 |
– |
*/ |
506 |
|
public NavigableSet<E> headSet(E toElement) { |
507 |
|
E least = s.getLeast(); |
508 |
|
if (!s.inOpenRange(toElement)) |
509 |
|
throw new IllegalArgumentException("element out of range"); |
510 |
< |
return new ConcurrentSkipListSubSet<E>(s.getMap(), |
510 |
> |
return new ConcurrentSkipListSubSet<E>(s.getMap(), |
511 |
|
least, toElement); |
512 |
|
} |
513 |
< |
|
711 |
< |
/** |
712 |
< |
* Returns a view of the portion of this set whose elements |
713 |
< |
* are greater than or equal to <tt>fromElement</tt>. The |
714 |
< |
* returned sorted set is backed by this set, so changes in |
715 |
< |
* the returned sorted set are reflected in this set, and |
716 |
< |
* vice-versa. |
717 |
< |
* @param fromElement low endpoint (inclusive) of the tailSet. |
718 |
< |
* @return a view of the portion of this set whose elements |
719 |
< |
* are greater than or equal to <tt>fromElement</tt>. |
720 |
< |
* @throws ClassCastException if <tt>fromElement</tt> is not |
721 |
< |
* compatible with this set's comparator (or, if the set has |
722 |
< |
* no comparator, if <tt>fromElement</tt> does not implement |
723 |
< |
* <tt>Comparable</tt>). |
724 |
< |
* @throws IllegalArgumentException if <tt>fromElement</tt> is |
725 |
< |
* outside the range of this set. |
726 |
< |
* @throws NullPointerException if <tt>fromElement</tt> is |
727 |
< |
* <tt>null</tt>. |
728 |
< |
*/ |
513 |
> |
|
514 |
|
public NavigableSet<E> tailSet(E fromElement) { |
515 |
|
E fence = s.getFence(); |
516 |
|
if (!s.inOpenRange(fromElement)) |
517 |
|
throw new IllegalArgumentException("element out of range"); |
518 |
< |
return new ConcurrentSkipListSubSet<E>(s.getMap(), |
518 |
> |
return new ConcurrentSkipListSubSet<E>(s.getMap(), |
519 |
|
fromElement, fence); |
520 |
|
} |
736 |
– |
} |
521 |
|
|
522 |
+ |
// relays to submap methods |
523 |
|
|
524 |
< |
} |
524 |
> |
public int size() { return s.size(); } |
525 |
> |
public boolean isEmpty() { return s.isEmpty(); } |
526 |
> |
public boolean contains(Object o) { return s.containsKey(o); } |
527 |
> |
public void clear() { s.clear(); } |
528 |
> |
public E first() { return s.firstKey(); } |
529 |
> |
public E last() { return s.lastKey(); } |
530 |
> |
public E ceiling(E o) { return s.ceilingKey(o); } |
531 |
> |
public E lower(E o) { return s.lowerKey(o); } |
532 |
> |
public E floor(E o) { return s.floorKey(o); } |
533 |
> |
public E higher(E o) { return s.higherKey(o); } |
534 |
> |
public boolean remove(Object o) { return s.remove(o)==Boolean.TRUE; } |
535 |
> |
public boolean add(E o) { return s.put(o, Boolean.TRUE)==null; } |
536 |
> |
public Comparator<? super E> comparator() { return s.comparator(); } |
537 |
> |
public Iterator<E> iterator() { return s.keySet().iterator(); } |
538 |
> |
public Iterator<E> descendingIterator() { |
539 |
> |
return s.descendingKeySet().iterator(); |
540 |
> |
} |
541 |
> |
public E pollFirst() { |
542 |
> |
Map.Entry<E,?> e = s.pollFirstEntry(); |
543 |
> |
return (e == null) ? null : e.getKey(); |
544 |
> |
} |
545 |
> |
public E pollLast() { |
546 |
> |
Map.Entry<E,?> e = s.pollLastEntry(); |
547 |
> |
return (e == null) ? null : e.getKey(); |
548 |
> |
} |
549 |
> |
|
550 |
> |
} |
551 |
> |
} |