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Comparing jsr166/src/jsr166x/ConcurrentSkipListMap.java (file contents):
Revision 1.11 by jsr166, Sat Nov 13 05:59:24 2010 UTC vs.
Revision 1.17 by jsr166, Tue Feb 21 01:54:03 2012 UTC

#	Line 1 | Line 1
1		/*
2		* Written by Doug Lea with assistance from members of JCP JSR-166
3		* Expert Group and released to the public domain, as explained at
4	<	* http://creativecommons.org/licenses/publicdomain
4	>	* http://creativecommons.org/publicdomain/zero/1.0/
5		*/
6
7		package jsr166x;
#	Line 325 | Line 325 | public class ConcurrentSkipListMap<K,V>
325		private transient DescendingEntrySet descendingEntrySet;
326
327		/**
328	<	* Initialize or reset state. Needed by constructors, clone,
328	>	* Initializes or resets state. Needed by constructors, clone,
329		* clear, readObject. and ConcurrentSkipListSet.clone.
330		* (Note that comparator must be separately initialized.)
331		*/
#	Line 414 | Line 414 | public class ConcurrentSkipListMap<K,V>
414		}
415
416		/**
417	<	* Return true if this node is a marker. This method isn't
417	>	* Returns true if this node is a marker. This method isn't
418		* actually called in an any current code checking for markers
419		* because callers will have already read value field and need
420		* to use that read (not another done here) and so directly
#	Line 427 | Line 427 | public class ConcurrentSkipListMap<K,V>
427		}
428
429		/**
430	<	* Return true if this node is the header of base-level list.
430	>	* Returns true if this node is the header of base-level list.
431		* @return true if this node is header node
432		*/
433		boolean isBaseHeader() {
#	Line 465 | Line 465 | public class ConcurrentSkipListMap<K,V>
465		}
466
467		/**
468	<	* Return value if this node contains a valid key-value pair,
468	>	* Returns value if this node contains a valid key-value pair,
469		* else null.
470		* @return this node's value if it isn't a marker or header or
471		* is deleted, else null.
#	Line 478 | Line 478 | public class ConcurrentSkipListMap<K,V>
478		}
479
480		/**
481	<	* Create and return a new SnapshotEntry holding current
482	<	* mapping if this node holds a valid value, else null
481	>	* Creates and returns a new SnapshotEntry holding current
482	>	* mapping if this node holds a valid value, else null.
483		* @return new entry or null
484		*/
485		SnapshotEntry<K,V> createSnapshot() {
#	Line 696 | Line 696 | public class ConcurrentSkipListMap<K,V>
696		}
697
698		/**
699	<	* Compare using comparator or natural ordering. Used when the
699	>	* Compares using comparator or natural ordering. Used when the
700		* ComparableUsingComparator approach doesn't apply.
701		*/
702		int compare(K k1, K k2) throws ClassCastException {
#	Line 708 | Line 708 | public class ConcurrentSkipListMap<K,V>
708		}
709
710		/**
711	<	* Return true if given key greater than or equal to least and
711	>	* Returns true if given key greater than or equal to least and
712		* strictly less than fence, bypassing either test if least or
713		* fence oare null. Needed mainly in submap operations.
714		*/
#	Line 720 | Line 720 | public class ConcurrentSkipListMap<K,V>
720		}
721
722		/**
723	<	* Return true if given key greater than or equal to least and less
723	>	* Returns true if given key greater than or equal to least and less
724		* or equal to fence. Needed mainly in submap operations.
725		*/
726		boolean inOpenRange(K key, K least, K fence) {
#	Line 733 | Line 733 | public class ConcurrentSkipListMap<K,V>
733		/* ---------------- Traversal -------------- */
734
735		/**
736	<	* Return a base-level node with key strictly less than given key,
736	>	* Returns a base-level node with key strictly less than given key,
737		* or the base-level header if there is no such node.  Also
738		* unlinks indexes to deleted nodes found along the way.  Callers
739		* rely on this side-effect of clearing indices to deleted nodes.
#	Line 766 | Line 766 | public class ConcurrentSkipListMap<K,V>
766		}
767
768		/**
769	<	* Return node holding key or null if no such, clearing out any
769	>	* Returns node holding key or null if no such, clearing out any
770		* deleted nodes seen along the way.  Repeatedly traverses at
771		* base-level looking for key starting at predecessor returned
772		* from findPredecessor, processing base-level deletions as
#	Line 865 | Line 865 | public class ConcurrentSkipListMap<K,V>
865		}
866		if (c == 0) {
867		Object v = r.node.value;
868	<	return (v != null)? (V)v : getUsingFindNode(key);
868	>	return (v != null) ? (V)v : getUsingFindNode(key);
869		}
870		bound = rk;
871		}
#	Line 878 | Line 878 | public class ConcurrentSkipListMap<K,V>
878		int c = key.compareTo(nk);
879		if (c == 0) {
880		Object v = n.value;
881	<	return (v != null)? (V)v : getUsingFindNode(key);
881	>	return (v != null) ? (V)v : getUsingFindNode(key);
882		}
883		if (c < 0)
884		return null;
#	Line 890 | Line 890 | public class ConcurrentSkipListMap<K,V>
890		}
891
892		/**
893	<	* Perform map.get via findNode.  Used as a backup if doGet
893	>	* Performs map.get via findNode.  Used as a backup if doGet
894		* encounters an in-progress deletion.
895		* @param key the key
896		* @return the value, or null if absent
#	Line 965 | Line 965 | public class ConcurrentSkipListMap<K,V>
965		}
966
967		/**
968	<	* Return a random level for inserting a new node.
968	>	* Returns a random level for inserting a new node.
969		* Hardwired to k=1, p=0.5, max 31.
970		*
971		* This uses a cheap pseudo-random function that according to
#	Line 987 | Line 987 | public class ConcurrentSkipListMap<K,V>
987		}
988
989		/**
990	<	* Create and add index nodes for given node.
990	>	* Creates and adds index nodes for given node.
991		* @param z the node
992		* @param level the level of the index
993		*/
#	Line 1039 | Line 1039 | public class ConcurrentSkipListMap<K,V>
1039		}
1040
1041		/**
1042	<	* Add given index nodes from given level down to 1.
1042	>	* Adds given index nodes from given level down to 1.
1043		* @param idx the topmost index node being inserted
1044		* @param h the value of head to use to insert. This must be
1045		* snapshotted by callers to provide correct insertion level
#	Line 1221 | Line 1221 | public class ConcurrentSkipListMap<K,V>
1221		}
1222
1223		/**
1224	<	* Remove first entry; return either its key or a snapshot.
1224	>	* Removes first entry; return either its key or a snapshot.
1225		* @param keyOnly if true return key, else return SnapshotEntry
1226		* (This is a little ugly, but avoids code duplication.)
1227		* @return null if empty, first key if keyOnly true, else key,value entry
#	Line 1246 | Line 1246 | public class ConcurrentSkipListMap<K,V>
1246		findFirst(); // retry
1247		clearIndexToFirst();
1248		K key = n.key;
1249	<	return (keyOnly)? key : new SnapshotEntry<K,V>(key, (V)v);
1249	>	return keyOnly ? key : new SnapshotEntry<K,V>(key, (V)v);
1250		}
1251		}
1252
1253		/**
1254	<	* Clear out index nodes associated with deleted first entry.
1255	<	* Needed by doRemoveFirst
1254	>	* Clears out index nodes associated with deleted first entry.
1255	>	* Needed by doRemoveFirst.
1256		*/
1257		private void clearIndexToFirst() {
1258		for (;;) {
#	Line 1271 | Line 1271 | public class ConcurrentSkipListMap<K,V>
1271		}
1272
1273		/**
1274	<	* Remove first entry; return key or null if empty.
1274	>	* Removes first entry; return key or null if empty.
1275		*/
1276		K pollFirstKey() {
1277		return (K)doRemoveFirst(true);
#	Line 1306 | Line 1306 | public class ConcurrentSkipListMap<K,V>
1306		Node<K,V> n = b.next;
1307		for (;;) {
1308		if (n == null)
1309	<	return (b.isBaseHeader())? null : b;
1309	>	return b.isBaseHeader() ? null : b;
1310		Node<K,V> f = n.next;            // inconsistent read
1311		if (n != b.next)
1312		break;
#	Line 1368 | Line 1368 | public class ConcurrentSkipListMap<K,V>
1368		if (head.right == null)
1369		tryReduceLevel();
1370		}
1371	<	return (keyOnly)? key : new SnapshotEntry<K,V>(key, (V)v);
1371	>	return keyOnly ? key : new SnapshotEntry<K,V>(key, (V)v);
1372		}
1373		}
1374		}
#	Line 1405 | Line 1405 | public class ConcurrentSkipListMap<K,V>
1405		}
1406
1407		/**
1408	<	* Remove last entry; return key or null if empty.
1408	>	* Removes last entry; return key or null if empty.
1409		*/
1410		K pollLastKey() {
1411		return (K)doRemoveLast(true);
#	Line 1432 | Line 1432 | public class ConcurrentSkipListMap<K,V>
1432		Node<K,V> n = b.next;
1433		for (;;) {
1434		if (n == null)
1435	<	return ((rel & LT) == 0 || b.isBaseHeader())? null : b;
1435	>	return ((rel & LT) == 0 || b.isBaseHeader()) ? null : b;
1436		Node<K,V> f = n.next;
1437		if (n != b.next)                  // inconsistent read
1438		break;
#	Line 1448 | Line 1448 | public class ConcurrentSkipListMap<K,V>
1448		(c <  0 && (rel & LT) == 0))
1449		return n;
1450		if ( c <= 0 && (rel & LT) != 0)
1451	<	return (b.isBaseHeader())? null : b;
1451	>	return b.isBaseHeader() ? null : b;
1452		b = n;
1453		n = f;
1454		}
#	Line 1456 | Line 1456 | public class ConcurrentSkipListMap<K,V>
1456		}
1457
1458		/**
1459	<	* Return SnapshotEntry for results of findNear.
1459	>	* Returns SnapshotEntry for results of findNear.
1460		* @param kkey the key
1461		* @param rel the relation -- OR'ed combination of EQ, LT, GT
1462		* @return Entry fitting relation, or null if no such
#	Line 1473 | Line 1473 | public class ConcurrentSkipListMap<K,V>
1473		}
1474
1475		/**
1476	<	* Return ceiling, or first node if key is <tt>null</tt>
1476	>	* Returns ceiling, or first node if key is <tt>null</tt>.
1477		*/
1478		Node<K,V> findCeiling(K key) {
1479	<	return (key == null)? findFirst() : findNear(key, GT|EQ);
1479	>	return (key == null) ? findFirst() : findNear(key, GT|EQ);
1480		}
1481
1482		/**
1483	<	* Return lower node, or last node if key is <tt>null</tt>
1483	>	* Returns lower node, or last node if key is <tt>null</tt>.
1484		*/
1485		Node<K,V> findLower(K key) {
1486	<	return (key == null)? findLast() : findNear(key, LT);
1486	>	return (key == null) ? findLast() : findNear(key, LT);
1487		}
1488
1489		/**
1490	<	* Return SnapshotEntry or key for results of findNear ofter screening
1490	>	* Returns SnapshotEntry or key for results of findNear ofter screening
1491		* to ensure result is in given range. Needed by submaps.
1492		* @param kkey the key
1493		* @param rel the relation -- OR'ed combination of EQ, LT, GT
#	Line 1513 | Line 1513 | public class ConcurrentSkipListMap<K,V>
1513		K k = n.key;
1514		V v = n.getValidValue();
1515		if (v != null)
1516	<	return keyOnly? k : new SnapshotEntry<K,V>(k, v);
1516	>	return keyOnly ? k : new SnapshotEntry<K,V>(k, v);
1517		}
1518		}
1519
1520		/**
1521	<	* Find and remove least element of subrange.
1521	>	* Finds and removes least element of subrange.
1522		* @param least minimum allowed key value
1523		* @param fence key greater than maximum allowed key value
1524		* @param keyOnly if true return key, else return SnapshotEntry
#	Line 1534 | Line 1534 | public class ConcurrentSkipListMap<K,V>
1534		return null;
1535		V v = doRemove(k, null);
1536		if (v != null)
1537	<	return (keyOnly)? k : new SnapshotEntry<K,V>(k, v);
1537	>	return keyOnly ? k : new SnapshotEntry<K,V>(k, v);
1538		}
1539		}
1540
1541		/**
1542	<	* Find and remove greatest element of subrange.
1542	>	* Finds and removes greatest element of subrange.
1543		* @param least minimum allowed key value
1544		* @param fence key greater than maximum allowed key value
1545		* @param keyOnly if true return key, else return SnapshotEntry
#	Line 1555 | Line 1555 | public class ConcurrentSkipListMap<K,V>
1555		return null;
1556		V v = doRemove(k, null);
1557		if (v != null)
1558	<	return (keyOnly)? k : new SnapshotEntry<K,V>(k, v);
1558	>	return keyOnly ? k : new SnapshotEntry<K,V>(k, v);
1559		}
1560		}
1561
#	Line 1689 | Line 1689 | public class ConcurrentSkipListMap<K,V>
1689		/* ---------------- Serialization -------------- */
1690
1691		/**
1692	<	* Save the state of the <tt>Map</tt> instance to a stream.
1692	>	* Saves the state of the <tt>Map</tt> instance to a stream.
1693		*
1694		* @serialData The key (Object) and value (Object) for each
1695		* key-value mapping represented by the Map, followed by
#	Line 1714 | Line 1714 | public class ConcurrentSkipListMap<K,V>
1714		}
1715
1716		/**
1717	<	* Reconstitute the <tt>Map</tt> instance from a stream.
1717	>	* Reconstitutes the <tt>Map</tt> instance from a stream.
1718		*/
1719		private void readObject(final java.io.ObjectInputStream s)
1720		throws java.io.IOException, ClassNotFoundException {
#	Line 1883 | Line 1883 | public class ConcurrentSkipListMap<K,V>
1883		if (n.getValidValue() != null)
1884		++count;
1885		}
1886	<	return (count >= Integer.MAX_VALUE)? Integer.MAX_VALUE : (int)count;
1886	>	return (count >= Integer.MAX_VALUE) ? Integer.MAX_VALUE : (int)count;
1887		}
1888
1889		/**
#	Line 2115 | Line 2115 | public class ConcurrentSkipListMap<K,V>
2115		}
2116
2117		/**
2118	<	* Remove entry for key only if currently mapped to given value.
2118	>	* Removes entry for key only if currently mapped to given value.
2119		* Acts as
2120		* <pre>
2121		*  if ((map.containsKey(key) && map.get(key).equals(value)) {
#	Line 2250 | Line 2250 | public class ConcurrentSkipListMap<K,V>
2250		* <tt>fromKey</tt> and <tt>toKey</tt> are equal, the returned sorted map
2251		* is empty.)  The returned sorted map is backed by this map, so changes
2252		* in the returned sorted map are reflected in this map, and vice-versa.
2253	<
2253	>	*
2254		* @param fromKey low endpoint (inclusive) of the subMap.
2255		* @param toKey high endpoint (exclusive) of the subMap.
2256		*
#	Line 2305 | Line 2305 | public class ConcurrentSkipListMap<K,V>
2305		* <tt>Comparable</tt>).
2306		* @throws NullPointerException if <tt>fromKey</tt> is <tt>null</tt>.
2307		*/
2308	<	public ConcurrentNavigableMap<K,V>  tailMap(K fromKey) {
2308	>	public ConcurrentNavigableMap<K,V> tailMap(K fromKey) {
2309		if (fromKey == null)
2310		throw new NullPointerException();
2311		return new ConcurrentSkipListSubMap(this, fromKey, null);
#	Line 2343 | Line 2343 | public class ConcurrentSkipListMap<K,V>
2343		*/
2344		public K ceilingKey(K key) {
2345		Node<K,V> n = findNear(key, GT|EQ);
2346	<	return (n == null)? null : n.key;
2346	>	return (n == null) ? null : n.key;
2347		}
2348
2349		/**
#	Line 2376 | Line 2376 | public class ConcurrentSkipListMap<K,V>
2376		*/
2377		public K lowerKey(K key) {
2378		Node<K,V> n = findNear(key, LT);
2379	<	return (n == null)? null : n.key;
2379	>	return (n == null) ? null : n.key;
2380		}
2381
2382		/**
#	Line 2410 | Line 2410 | public class ConcurrentSkipListMap<K,V>
2410		*/
2411		public K floorKey(K key) {
2412		Node<K,V> n = findNear(key, LT|EQ);
2413	<	return (n == null)? null : n.key;
2413	>	return (n == null) ? null : n.key;
2414		}
2415
2416		/**
#	Line 2443 | Line 2443 | public class ConcurrentSkipListMap<K,V>
2443		*/
2444		public K higherKey(K key) {
2445		Node<K,V> n = findNear(key, GT);
2446	<	return (n == null)? null : n.key;
2446	>	return (n == null) ? null : n.key;
2447		}
2448
2449		/**
#	Line 3128 | Line 3128 | public class ConcurrentSkipListMap<K,V>
3128
3129		public V get(Object key) {
3130		K k = (K)key;
3131	<	return ((!inHalfOpenRange(k)) ? null : m.get(k));
3131	>	return (!inHalfOpenRange(k)) ? null : m.get(k);
3132		}
3133
3134		public V put(K key, V value) {
#	Line 3138 | Line 3138 | public class ConcurrentSkipListMap<K,V>
3138
3139		public V remove(Object key) {
3140		K k = (K)key;
3141	<	return (!inHalfOpenRange(k))? null : m.remove(k);
3141	>	return (!inHalfOpenRange(k)) ? null : m.remove(k);
3142		}
3143
3144		public int size() {
#	Line 3149 | Line 3149 | public class ConcurrentSkipListMap<K,V>
3149		if (n.getValidValue() != null)
3150		++count;
3151		}
3152	<	return count >= Integer.MAX_VALUE? Integer.MAX_VALUE : (int)count;
3152	>	return (count >= Integer.MAX_VALUE) ?
3153	>	Integer.MAX_VALUE : (int)count;
3154		}
3155
3156		public boolean isEmpty() {
#	Line 3240 | Line 3241 | public class ConcurrentSkipListMap<K,V>
3241		return new ConcurrentSkipListSubMap(m, least, toKey);
3242		}
3243
3244	<	public  ConcurrentNavigableMap<K,V> tailMap(K fromKey) {
3244	>	public ConcurrentNavigableMap<K,V> tailMap(K fromKey) {
3245		if (fromKey == null)
3246		throw new NullPointerException();
3247		if (!inOpenRange(fromKey))

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