jdk1.7之TreeMap

public class TreeMap<K, V> extends AbstractMap<K, V> implements NavigableMap<K, V>, Cloneable, java.io.Serializable {


private final Comparator<? super K> comparator;


private transient Entry<K, V> root = null;


private transient int size = 0;


private transient int modCount = 0;


public TreeMap() {
comparator = null;
}


public TreeMap(Comparator<? super K> comparator) {
this.comparator = comparator;
}


public TreeMap(Map<? extends K, ? extends V> m) {
comparator = null;
putAll(m);
}


public TreeMap(SortedMap<K, ? extends V> m) {
comparator = m.comparator();
try {
buildFromSorted(m.size(), m.entrySet().iterator(), null, null);
} catch (java.io.IOException cannotHappen) {
} catch (ClassNotFoundException cannotHappen) {
}
}


// Query Operations


public int size() {
return size;
}


public boolean containsKey(Object key) {
return getEntry(key) != null;
}


public boolean containsValue(Object value) {
for (Entry<K, V> e = getFirstEntry(); e != null; e = successor(e))
if (valEquals(value, e.value))
return true;
return false;
}


public V get(Object key) {
Entry<K, V> p = getEntry(key);
return (p == null ? null : p.value);
}


public Comparator<? super K> comparator() {
return comparator;
}


public K firstKey() {
return key(getFirstEntry());
}


public K lastKey() {
return key(getLastEntry());
}


public void putAll(Map<? extends K, ? extends V> map) {
int mapSize = map.size();
if (size == 0 && mapSize != 0 && map instanceof SortedMap) {
Comparator c = ((SortedMap) map).comparator();
if (c == comparator || (c != null && c.equals(comparator))) {
++modCount;
try {
buildFromSorted(mapSize, map.entrySet().iterator(), null, null);
} catch (java.io.IOException cannotHappen) {
} catch (ClassNotFoundException cannotHappen) {
}
return;
}
}
super.putAll(map);
}


final Entry<K, V> getEntry(Object key) {
// Offload comparator-based version for sake of performance
if (comparator != null)
return getEntryUsingComparator(key);
if (key == null)
throw new NullPointerException();
Comparable<? super K> k = (Comparable<? super K>) key;
Entry<K, V> p = root;
while (p != null) {
int cmp = k.compareTo(p.key);
if (cmp < 0)
p = p.left;
else if (cmp > 0)
p = p.right;
else
return p;
}
return null;
}


final Entry<K, V> getEntryUsingComparator(Object key) {
K k = (K) key;
Comparator<? super K> cpr = comparator;
if (cpr != null) {
Entry<K, V> p = root;
while (p != null) {
int cmp = cpr.compare(k, p.key);
if (cmp < 0)
p = p.left;
else if (cmp > 0)
p = p.right;
else
return p;
}
}
return null;
}


final Entry<K, V> getCeilingEntry(K key) {
Entry<K, V> p = root;
while (p != null) {
int cmp = compare(key, p.key);
if (cmp < 0) {
if (p.left != null)
p = p.left;
else
return p;
} else if (cmp > 0) {
if (p.right != null) {
p = p.right;
} else {
Entry<K, V> parent = p.parent;
Entry<K, V> ch = p;
while (parent != null && ch == parent.right) {
ch = parent;
parent = parent.parent;
}
return parent;
}
} else
return p;
}
return null;
}


final Entry<K, V> getFloorEntry(K key) {
Entry<K, V> p = root;
while (p != null) {
int cmp = compare(key, p.key);
if (cmp > 0) {
if (p.right != null)
p = p.right;
else
return p;
} else if (cmp < 0) {
if (p.left != null) {
p = p.left;
} else {
Entry<K, V> parent = p.parent;
Entry<K, V> ch = p;
while (parent != null && ch == parent.left) {
ch = parent;
parent = parent.parent;
}
return parent;
}
} else
return p;


}
return null;
}


final Entry<K, V> getHigherEntry(K key) {
Entry<K, V> p = root;
while (p != null) {
int cmp = compare(key, p.key);
if (cmp < 0) {
if (p.left != null)
p = p.left;
else
return p;
} else {
if (p.right != null) {
p = p.right;
} else {
Entry<K, V> parent = p.parent;
Entry<K, V> ch = p;
while (parent != null && ch == parent.right) {
ch = parent;
parent = parent.parent;
}
return parent;
}
}
}
return null;
}


final Entry<K, V> getLowerEntry(K key) {
Entry<K, V> p = root;
while (p != null) {
int cmp = compare(key, p.key);
if (cmp > 0) {
if (p.right != null)
p = p.right;
else
return p;
} else {
if (p.left != null) {
p = p.left;
} else {
Entry<K, V> parent = p.parent;
Entry<K, V> ch = p;
while (parent != null && ch == parent.left) {
ch = parent;
parent = parent.parent;
}
return parent;
}
}
}
return null;
}


public V put(K key, V value) {
Entry<K, V> t = root;
if (t == null) {
compare(key, key); // type (and possibly null) check


root = new Entry<>(key, value, null);
size = 1;
modCount++;
return null;
}
int cmp;
Entry<K, V> parent;
// split comparator and comparable paths
Comparator<? super K> cpr = comparator;
if (cpr != null) {
do {
parent = t;
cmp = cpr.compare(key, t.key);
if (cmp < 0)
t = t.left;
else if (cmp > 0)
t = t.right;
else
return t.setValue(value);
} while (t != null);
} else {
if (key == null)
throw new NullPointerException();
Comparable<? super K> k = (Comparable<? super K>) key;
do {
parent = t;
cmp = k.compareTo(t.key);
if (cmp < 0)
t = t.left;
else if (cmp > 0)
t = t.right;
else
return t.setValue(value);
} while (t != null);
}
Entry<K, V> e = new Entry<>(key, value, parent);
if (cmp < 0)
parent.left = e;
else
parent.right = e;
fixAfterInsertion(e);
size++;
modCount++;
return null;
}


public V remove(Object key) {
Entry<K, V> p = getEntry(key);
if (p == null)
return null;


V oldValue = p.value;
deleteEntry(p);
return oldValue;
}




public void clear() {
modCount++;
size = 0;
root = null;
}




public Object clone() {
TreeMap<K, V> clone = null;
try {
clone = (TreeMap<K, V>) super.clone();
} catch (CloneNotSupportedException e) {
throw new InternalError();
}


// Put clone into "virgin" state (except for comparator)
clone.root = null;
clone.size = 0;
clone.modCount = 0;
clone.entrySet = null;
clone.navigableKeySet = null;
clone.descendingMap = null;


// Initialize clone with our mappings
try {
clone.buildFromSorted(size, entrySet().iterator(), null, null);
} catch (java.io.IOException cannotHappen) {
} catch (ClassNotFoundException cannotHappen) {
}


return clone;
}


// NavigableMap API methods


public Map.Entry<K, V> firstEntry() {
return exportEntry(getFirstEntry());
}


public Map.Entry<K, V> lastEntry() {
return exportEntry(getLastEntry());
}


public Map.Entry<K, V> pollFirstEntry() {
Entry<K, V> p = getFirstEntry();
Map.Entry<K, V> result = exportEntry(p);
if (p != null)
deleteEntry(p);
return result;
}


public Map.Entry<K, V> pollLastEntry() {
Entry<K, V> p = getLastEntry();
Map.Entry<K, V> result = exportEntry(p);
if (p != null)
deleteEntry(p);
return result;
}


public Map.Entry<K, V> lowerEntry(K key) {
return exportEntry(getLowerEntry(key));
}


public K lowerKey(K key) {
return keyOrNull(getLowerEntry(key));
}


public Map.Entry<K, V> floorEntry(K key) {
return exportEntry(getFloorEntry(key));
}


public K floorKey(K key) {
return keyOrNull(getFloorEntry(key));
}


public Map.Entry<K, V> ceilingEntry(K key) {
return exportEntry(getCeilingEntry(key));
}


public K ceilingKey(K key) {
return keyOrNull(getCeilingEntry(key));
}


public Map.Entry<K, V> higherEntry(K key) {
return exportEntry(getHigherEntry(key));
}


public K higherKey(K key) {
return keyOrNull(getHigherEntry(key));
}


// Views


private transient EntrySet entrySet = null;
private transient KeySet<K> navigableKeySet = null;
private transient NavigableMap<K, V> descendingMap = null;


public Set<K> keySet() {
return navigableKeySet();
}




public NavigableSet<K> navigableKeySet() {
KeySet<K> nks = navigableKeySet;
return (nks != null) ? nks : (navigableKeySet = new KeySet(this));
}


public NavigableSet<K> descendingKeySet() {
return descendingMap().navigableKeySet();
}


public Collection<V> values() {
Collection<V> vs = values;
return (vs != null) ? vs : (values = new Values());
}


public Set<Map.Entry<K, V>> entrySet() {
EntrySet es = entrySet;
return (es != null) ? es : (entrySet = new EntrySet());
}


/**
* @since 1.6
*/
public NavigableMap<K, V> descendingMap() {
NavigableMap<K, V> km = descendingMap;
return (km != null) ? km : (descendingMap = new DescendingSubMap(this, true, null, true, true, null, true));
}


public NavigableMap<K, V> subMap(K fromKey, boolean fromInclusive, K toKey, boolean toInclusive) {
return new AscendingSubMap(this, false, fromKey, fromInclusive, false, toKey, toInclusive);
}


public NavigableMap<K, V> headMap(K toKey, boolean inclusive) {
return new AscendingSubMap(this, true, null, true, false, toKey, inclusive);
}


public NavigableMap<K, V> tailMap(K fromKey, boolean inclusive) {
return new AscendingSubMap(this, false, fromKey, inclusive, true, null, true);
}


public SortedMap<K, V> subMap(K fromKey, K toKey) {
return subMap(fromKey, true, toKey, false);
}


public SortedMap<K, V> headMap(K toKey) {
return headMap(toKey, false);
}


public SortedMap<K, V> tailMap(K fromKey) {
return tailMap(fromKey, true);
}


// View class support


class Values extends AbstractCollection<V> {
public Iterator<V> iterator() {
return new ValueIterator(getFirstEntry());
}


public int size() {
return TreeMap.this.size();
}


public boolean contains(Object o) {
return TreeMap.this.containsValue(o);
}


public boolean remove(Object o) {
for (Entry<K, V> e = getFirstEntry(); e != null; e = successor(e)) {
if (valEquals(e.getValue(), o)) {
deleteEntry(e);
return true;
}
}
return false;
}


public void clear() {
TreeMap.this.clear();
}
}


class EntrySet extends AbstractSet<Map.Entry<K, V>> {
public Iterator<Map.Entry<K, V>> iterator() {
return new EntryIterator(getFirstEntry());
}


public boolean contains(Object o) {
if (!(o instanceof Map.Entry))
return false;
Map.Entry<K, V> entry = (Map.Entry<K, V>) o;
V value = entry.getValue();
Entry<K, V> p = getEntry(entry.getKey());
return p != null && valEquals(p.getValue(), value);
}


public boolean remove(Object o) {
if (!(o instanceof Map.Entry))
return false;
Map.Entry<K, V> entry = (Map.Entry<K, V>) o;
V value = entry.getValue();
Entry<K, V> p = getEntry(entry.getKey());
if (p != null && valEquals(p.getValue(), value)) {
deleteEntry(p);
return true;
}
return false;
}


public int size() {
return TreeMap.this.size();
}


public void clear() {
TreeMap.this.clear();
}
}


Iterator<K> keyIterator() {
return new KeyIterator(getFirstEntry());
}


Iterator<K> descendingKeyIterator() {
return new DescendingKeyIterator(getLastEntry());
}


static final class KeySet<E> extends AbstractSet<E> implements NavigableSet<E> {
private final NavigableMap<E, Object> m;


KeySet(NavigableMap<E, Object> map) {
m = map;
}


public Iterator<E> iterator() {
if (m instanceof TreeMap)
return ((TreeMap<E, Object>) m).keyIterator();
else
return (Iterator<E>) (((TreeMap.NavigableSubMap) m).keyIterator());
}


public Iterator<E> descendingIterator() {
if (m instanceof TreeMap)
return ((TreeMap<E, Object>) m).descendingKeyIterator();
else
return (Iterator<E>) (((TreeMap.NavigableSubMap) m).descendingKeyIterator());
}


public int size() {
return m.size();
}


public boolean isEmpty() {
return m.isEmpty();
}


public boolean contains(Object o) {
return m.containsKey(o);
}


public void clear() {
m.clear();
}


public E lower(E e) {
return m.lowerKey(e);
}


public E floor(E e) {
return m.floorKey(e);
}


public E ceiling(E e) {
return m.ceilingKey(e);
}


public E higher(E e) {
return m.higherKey(e);
}


public E first() {
return m.firstKey();
}


public E last() {
return m.lastKey();
}


public Comparator<? super E> comparator() {
return m.comparator();
}


public E pollFirst() {
Map.Entry<E, Object> e = m.pollFirstEntry();
return (e == null) ? null : e.getKey();
}


public E pollLast() {
Map.Entry<E, Object> e = m.pollLastEntry();
return (e == null) ? null : e.getKey();
}


public boolean remove(Object o) {
int oldSize = size();
m.remove(o);
return size() != oldSize;
}


public NavigableSet<E> subSet(E fromElement, boolean fromInclusive, E toElement, boolean toInclusive) {
return new KeySet<>(m.subMap(fromElement, fromInclusive, toElement, toInclusive));
}


public NavigableSet<E> headSet(E toElement, boolean inclusive) {
return new KeySet<>(m.headMap(toElement, inclusive));
}


public NavigableSet<E> tailSet(E fromElement, boolean inclusive) {
return new KeySet<>(m.tailMap(fromElement, inclusive));
}


public SortedSet<E> subSet(E fromElement, E toElement) {
return subSet(fromElement, true, toElement, false);
}


public SortedSet<E> headSet(E toElement) {
return headSet(toElement, false);
}


public SortedSet<E> tailSet(E fromElement) {
return tailSet(fromElement, true);
}


public NavigableSet<E> descendingSet() {
return new KeySet(m.descendingMap());
}
}


/**
* Base class for TreeMap Iterators
*/
abstract class PrivateEntryIterator<T> implements Iterator<T> {
Entry<K, V> next;
Entry<K, V> lastReturned;
int expectedModCount;


PrivateEntryIterator(Entry<K, V> first) {
expectedModCount = modCount;
lastReturned = null;
next = first;
}


public final boolean hasNext() {
return next != null;
}


final Entry<K, V> nextEntry() {
Entry<K, V> e = next;
if (e == null)
throw new NoSuchElementException();
if (modCount != expectedModCount)
throw new ConcurrentModificationException();
next = successor(e);
lastReturned = e;
return e;
}


final Entry<K, V> prevEntry() {
Entry<K, V> e = next;
if (e == null)
throw new NoSuchElementException();
if (modCount != expectedModCount)
throw new ConcurrentModificationException();
next = predecessor(e);
lastReturned = e;
return e;
}


public void remove() {
if (lastReturned == null)
throw new IllegalStateException();
if (modCount != expectedModCount)
throw new ConcurrentModificationException();
// deleted entries are replaced by their successors
if (lastReturned.left != null && lastReturned.right != null)
next = lastReturned;
deleteEntry(lastReturned);
expectedModCount = modCount;
lastReturned = null;
}
}


final class EntryIterator extends PrivateEntryIterator<Map.Entry<K, V>> {
EntryIterator(Entry<K, V> first) {
super(first);
}


public Map.Entry<K, V> next() {
return nextEntry();
}
}


final class ValueIterator extends PrivateEntryIterator<V> {
ValueIterator(Entry<K, V> first) {
super(first);
}


public V next() {
return nextEntry().value;
}
}


final class KeyIterator extends PrivateEntryIterator<K> {
KeyIterator(Entry<K, V> first) {
super(first);
}


public K next() {
return nextEntry().key;
}
}


final class DescendingKeyIterator extends PrivateEntryIterator<K> {
DescendingKeyIterator(Entry<K, V> first) {
super(first);
}


public K next() {
return prevEntry().key;
}
}


// Little utilities


final int compare(Object k1, Object k2) {
return comparator == null ? ((Comparable<? super K>) k1).compareTo((K) k2) : comparator.compare((K) k1, (K) k2);
}


static final boolean valEquals(Object o1, Object o2) {
return (o1 == null ? o2 == null : o1.equals(o2));
}


static <K, V> Map.Entry<K, V> exportEntry(TreeMap.Entry<K, V> e) {
return (e == null) ? null : new AbstractMap.SimpleImmutableEntry<>(e);
}


static <K, V> K keyOrNull(TreeMap.Entry<K, V> e) {
return (e == null) ? null : e.key;
}


static <K> K key(Entry<K, ?> e) {
if (e == null)
throw new NoSuchElementException();
return e.key;
}


// SubMaps


private static final Object UNBOUNDED = new Object();


abstract static class NavigableSubMap<K, V> extends AbstractMap<K, V>
implements NavigableMap<K, V>, java.io.Serializable {

final TreeMap<K, V> m;


final K lo, hi;
final boolean fromStart, toEnd;
final boolean loInclusive, hiInclusive;


NavigableSubMap(TreeMap<K, V> m, boolean fromStart, K lo, boolean loInclusive, boolean toEnd, K hi,
boolean hiInclusive) {
if (!fromStart && !toEnd) {
if (m.compare(lo, hi) > 0)
throw new IllegalArgumentException("fromKey > toKey");
} else {
if (!fromStart) // type check
m.compare(lo, lo);
if (!toEnd)
m.compare(hi, hi);
}


this.m = m;
this.fromStart = fromStart;
this.lo = lo;
this.loInclusive = loInclusive;
this.toEnd = toEnd;
this.hi = hi;
this.hiInclusive = hiInclusive;
}


// internal utilities


final boolean tooLow(Object key) {
if (!fromStart) {
int c = m.compare(key, lo);
if (c < 0 || (c == 0 && !loInclusive))
return true;
}
return false;
}


final boolean tooHigh(Object key) {
if (!toEnd) {
int c = m.compare(key, hi);
if (c > 0 || (c == 0 && !hiInclusive))
return true;
}
return false;
}


final boolean inRange(Object key) {
return !tooLow(key) && !tooHigh(key);
}


final boolean inClosedRange(Object key) {
return (fromStart || m.compare(key, lo) >= 0) && (toEnd || m.compare(hi, key) >= 0);
}


final boolean inRange(Object key, boolean inclusive) {
return inclusive ? inRange(key) : inClosedRange(key);
}


/*
* Absolute versions of relation operations. Subclasses map to these
* using like-named "sub" versions that invert senses for descending
* maps
*/


final TreeMap.Entry<K, V> absLowest() {
TreeMap.Entry<K, V> e = (fromStart ? m.getFirstEntry()
: (loInclusive ? m.getCeilingEntry(lo) : m.getHigherEntry(lo)));
return (e == null || tooHigh(e.key)) ? null : e;
}


final TreeMap.Entry<K, V> absHighest() {
TreeMap.Entry<K, V> e = (toEnd ? m.getLastEntry()
: (hiInclusive ? m.getFloorEntry(hi) : m.getLowerEntry(hi)));
return (e == null || tooLow(e.key)) ? null : e;
}


final TreeMap.Entry<K, V> absCeiling(K key) {
if (tooLow(key))
return absLowest();
TreeMap.Entry<K, V> e = m.getCeilingEntry(key);
return (e == null || tooHigh(e.key)) ? null : e;
}


final TreeMap.Entry<K, V> absHigher(K key) {
if (tooLow(key))
return absLowest();
TreeMap.Entry<K, V> e = m.getHigherEntry(key);
return (e == null || tooHigh(e.key)) ? null : e;
}


final TreeMap.Entry<K, V> absFloor(K key) {
if (tooHigh(key))
return absHighest();
TreeMap.Entry<K, V> e = m.getFloorEntry(key);
return (e == null || tooLow(e.key)) ? null : e;
}


final TreeMap.Entry<K, V> absLower(K key) {
if (tooHigh(key))
return absHighest();
TreeMap.Entry<K, V> e = m.getLowerEntry(key);
return (e == null || tooLow(e.key)) ? null : e;
}


/** Returns the absolute high fence for ascending traversal */
final TreeMap.Entry<K, V> absHighFence() {
return (toEnd ? null : (hiInclusive ? m.getHigherEntry(hi) : m.getCeilingEntry(hi)));
}


/** Return the absolute low fence for descending traversal */
final TreeMap.Entry<K, V> absLowFence() {
return (fromStart ? null : (loInclusive ? m.getLowerEntry(lo) : m.getFloorEntry(lo)));
}


// Abstract methods defined in ascending vs descending classes
// These relay to the appropriate absolute versions


abstract TreeMap.Entry<K, V> subLowest();


abstract TreeMap.Entry<K, V> subHighest();


abstract TreeMap.Entry<K, V> subCeiling(K key);


abstract TreeMap.Entry<K, V> subHigher(K key);


abstract TreeMap.Entry<K, V> subFloor(K key);


abstract TreeMap.Entry<K, V> subLower(K key);


/** Returns ascending iterator from the perspective of this submap */
abstract Iterator<K> keyIterator();


/** Returns descending iterator from the perspective of this submap */
abstract Iterator<K> descendingKeyIterator();


// public methods


public boolean isEmpty() {
return (fromStart && toEnd) ? m.isEmpty() : entrySet().isEmpty();
}


public int size() {
return (fromStart && toEnd) ? m.size() : entrySet().size();
}


public final boolean containsKey(Object key) {
return inRange(key) && m.containsKey(key);
}


public final V put(K key, V value) {
if (!inRange(key))
throw new IllegalArgumentException("key out of range");
return m.put(key, value);
}


public final V get(Object key) {
return !inRange(key) ? null : m.get(key);
}


public final V remove(Object key) {
return !inRange(key) ? null : m.remove(key);
}


public final Map.Entry<K, V> ceilingEntry(K key) {
return exportEntry(subCeiling(key));
}


public final K ceilingKey(K key) {
return keyOrNull(subCeiling(key));
}


public final Map.Entry<K, V> higherEntry(K key) {
return exportEntry(subHigher(key));
}


public final K higherKey(K key) {
return keyOrNull(subHigher(key));
}


public final Map.Entry<K, V> floorEntry(K key) {
return exportEntry(subFloor(key));
}


public final K floorKey(K key) {
return keyOrNull(subFloor(key));
}


public final Map.Entry<K, V> lowerEntry(K key) {
return exportEntry(subLower(key));
}


public final K lowerKey(K key) {
return keyOrNull(subLower(key));
}


public final K firstKey() {
return key(subLowest());
}


public final K lastKey() {
return key(subHighest());
}


public final Map.Entry<K, V> firstEntry() {
return exportEntry(subLowest());
}


public final Map.Entry<K, V> lastEntry() {
return exportEntry(subHighest());
}


public final Map.Entry<K, V> pollFirstEntry() {
TreeMap.Entry<K, V> e = subLowest();
Map.Entry<K, V> result = exportEntry(e);
if (e != null)
m.deleteEntry(e);
return result;
}


public final Map.Entry<K, V> pollLastEntry() {
TreeMap.Entry<K, V> e = subHighest();
Map.Entry<K, V> result = exportEntry(e);
if (e != null)
m.deleteEntry(e);
return result;
}


// Views
transient NavigableMap<K, V> descendingMapView = null;
transient EntrySetView entrySetView = null;
transient KeySet<K> navigableKeySetView = null;


public final NavigableSet<K> navigableKeySet() {
KeySet<K> nksv = navigableKeySetView;
return (nksv != null) ? nksv : (navigableKeySetView = new TreeMap.KeySet(this));
}


public final Set<K> keySet() {
return navigableKeySet();
}


public NavigableSet<K> descendingKeySet() {
return descendingMap().navigableKeySet();
}


public final SortedMap<K, V> subMap(K fromKey, K toKey) {
return subMap(fromKey, true, toKey, false);
}


public final SortedMap<K, V> headMap(K toKey) {
return headMap(toKey, false);
}


public final SortedMap<K, V> tailMap(K fromKey) {
return tailMap(fromKey, true);
}


// View classes


abstract class EntrySetView extends AbstractSet<Map.Entry<K, V>> {
private transient int size = -1, sizeModCount;


public int size() {
if (fromStart && toEnd)
return m.size();
if (size == -1 || sizeModCount != m.modCount) {
sizeModCount = m.modCount;
size = 0;
Iterator i = iterator();
while (i.hasNext()) {
size++;
i.next();
}
}
return size;
}


public boolean isEmpty() {
TreeMap.Entry<K, V> n = absLowest();
return n == null || tooHigh(n.key);
}


public boolean contains(Object o) {
if (!(o instanceof Map.Entry))
return false;
Map.Entry<K, V> entry = (Map.Entry<K, V>) o;
K key = entry.getKey();
if (!inRange(key))
return false;
TreeMap.Entry node = m.getEntry(key);
return node != null && valEquals(node.getValue(), entry.getValue());
}


public boolean remove(Object o) {
if (!(o instanceof Map.Entry))
return false;
Map.Entry<K, V> entry = (Map.Entry<K, V>) o;
K key = entry.getKey();
if (!inRange(key))
return false;
TreeMap.Entry<K, V> node = m.getEntry(key);
if (node != null && valEquals(node.getValue(), entry.getValue())) {
m.deleteEntry(node);
return true;
}
return false;
}
}


/**
* Iterators for SubMaps
*/
abstract class SubMapIterator<T> implements Iterator<T> {
TreeMap.Entry<K, V> lastReturned;
TreeMap.Entry<K, V> next;
final Object fenceKey;
int expectedModCount;


SubMapIterator(TreeMap.Entry<K, V> first, TreeMap.Entry<K, V> fence) {
expectedModCount = m.modCount;
lastReturned = null;
next = first;
fenceKey = fence == null ? UNBOUNDED : fence.key;
}


public final boolean hasNext() {
return next != null && next.key != fenceKey;
}


final TreeMap.Entry<K, V> nextEntry() {
TreeMap.Entry<K, V> e = next;
if (e == null || e.key == fenceKey)
throw new NoSuchElementException();
if (m.modCount != expectedModCount)
throw new ConcurrentModificationException();
next = successor(e);
lastReturned = e;
return e;
}


final TreeMap.Entry<K, V> prevEntry() {
TreeMap.Entry<K, V> e = next;
if (e == null || e.key == fenceKey)
throw new NoSuchElementException();
if (m.modCount != expectedModCount)
throw new ConcurrentModificationException();
next = predecessor(e);
lastReturned = e;
return e;
}


final void removeAscending() {
if (lastReturned == null)
throw new IllegalStateException();
if (m.modCount != expectedModCount)
throw new ConcurrentModificationException();
// deleted entries are replaced by their successors
if (lastReturned.left != null && lastReturned.right != null)
next = lastReturned;
m.deleteEntry(lastReturned);
lastReturned = null;
expectedModCount = m.modCount;
}


final void removeDescending() {
if (lastReturned == null)
throw new IllegalStateException();
if (m.modCount != expectedModCount)
throw new ConcurrentModificationException();
m.deleteEntry(lastReturned);
lastReturned = null;
expectedModCount = m.modCount;
}


}


final class SubMapEntryIterator extends SubMapIterator<Map.Entry<K, V>> {
SubMapEntryIterator(TreeMap.Entry<K, V> first, TreeMap.Entry<K, V> fence) {
super(first, fence);
}


public Map.Entry<K, V> next() {
return nextEntry();
}


public void remove() {
removeAscending();
}
}


final class SubMapKeyIterator extends SubMapIterator<K> {
SubMapKeyIterator(TreeMap.Entry<K, V> first, TreeMap.Entry<K, V> fence) {
super(first, fence);
}


public K next() {
return nextEntry().key;
}


public void remove() {
removeAscending();
}
}


final class DescendingSubMapEntryIterator extends SubMapIterator<Map.Entry<K, V>> {
DescendingSubMapEntryIterator(TreeMap.Entry<K, V> last, TreeMap.Entry<K, V> fence) {
super(last, fence);
}


public Map.Entry<K, V> next() {
return prevEntry();
}


public void remove() {
removeDescending();
}
}


final class DescendingSubMapKeyIterator extends SubMapIterator<K> {
DescendingSubMapKeyIterator(TreeMap.Entry<K, V> last, TreeMap.Entry<K, V> fence) {
super(last, fence);
}


public K next() {
return prevEntry().key;
}


public void remove() {
removeDescending();
}
}
}


/**
* @serial include
*/
static final class AscendingSubMap<K, V> extends NavigableSubMap<K, V> {
private static final long serialVersionUID = 912986545866124060L;


AscendingSubMap(TreeMap<K, V> m, boolean fromStart, K lo, boolean loInclusive, boolean toEnd, K hi,
boolean hiInclusive) {
super(m, fromStart, lo, loInclusive, toEnd, hi, hiInclusive);
}


public Comparator<? super K> comparator() {
return m.comparator();
}


public NavigableMap<K, V> subMap(K fromKey, boolean fromInclusive, K toKey, boolean toInclusive) {
if (!inRange(fromKey, fromInclusive))
throw new IllegalArgumentException("fromKey out of range");
if (!inRange(toKey, toInclusive))
throw new IllegalArgumentException("toKey out of range");
return new AscendingSubMap(m, false, fromKey, fromInclusive, false, toKey, toInclusive);
}


public NavigableMap<K, V> headMap(K toKey, boolean inclusive) {
if (!inRange(toKey, inclusive))
throw new IllegalArgumentException("toKey out of range");
return new AscendingSubMap(m, fromStart, lo, loInclusive, false, toKey, inclusive);
}


public NavigableMap<K, V> tailMap(K fromKey, boolean inclusive) {
if (!inRange(fromKey, inclusive))
throw new IllegalArgumentException("fromKey out of range");
return new AscendingSubMap(m, false, fromKey, inclusive, toEnd, hi, hiInclusive);
}


public NavigableMap<K, V> descendingMap() {
NavigableMap<K, V> mv = descendingMapView;
return (mv != null) ? mv
: (descendingMapView = new DescendingSubMap(m, fromStart, lo, loInclusive, toEnd, hi, hiInclusive));
}


Iterator<K> keyIterator() {
return new SubMapKeyIterator(absLowest(), absHighFence());
}


Iterator<K> descendingKeyIterator() {
return new DescendingSubMapKeyIterator(absHighest(), absLowFence());
}


final class AscendingEntrySetView extends EntrySetView {
public Iterator<Map.Entry<K, V>> iterator() {
return new SubMapEntryIterator(absLowest(), absHighFence());
}
}


public Set<Map.Entry<K, V>> entrySet() {
EntrySetView es = entrySetView;
return (es != null) ? es : new AscendingEntrySetView();
}


TreeMap.Entry<K, V> subLowest() {
return absLowest();
}


TreeMap.Entry<K, V> subHighest() {
return absHighest();
}


TreeMap.Entry<K, V> subCeiling(K key) {
return absCeiling(key);
}


TreeMap.Entry<K, V> subHigher(K key) {
return absHigher(key);
}


TreeMap.Entry<K, V> subFloor(K key) {
return absFloor(key);
}


TreeMap.Entry<K, V> subLower(K key) {
return absLower(key);
}
}


/**
* @serial include
*/
static final class DescendingSubMap<K, V> extends NavigableSubMap<K, V> {
private static final long serialVersionUID = 912986545866120460L;


DescendingSubMap(TreeMap<K, V> m, boolean fromStart, K lo, boolean loInclusive, boolean toEnd, K hi,
boolean hiInclusive) {
super(m, fromStart, lo, loInclusive, toEnd, hi, hiInclusive);
}


private final Comparator<? super K> reverseComparator = Collections.reverseOrder(m.comparator);


public Comparator<? super K> comparator() {
return reverseComparator;
}


public NavigableMap<K, V> subMap(K fromKey, boolean fromInclusive, K toKey, boolean toInclusive) {
if (!inRange(fromKey, fromInclusive))
throw new IllegalArgumentException("fromKey out of range");
if (!inRange(toKey, toInclusive))
throw new IllegalArgumentException("toKey out of range");
return new DescendingSubMap(m, false, toKey, toInclusive, false, fromKey, fromInclusive);
}


public NavigableMap<K, V> headMap(K toKey, boolean inclusive) {
if (!inRange(toKey, inclusive))
throw new IllegalArgumentException("toKey out of range");
return new DescendingSubMap(m, false, toKey, inclusive, toEnd, hi, hiInclusive);
}


public NavigableMap<K, V> tailMap(K fromKey, boolean inclusive) {
if (!inRange(fromKey, inclusive))
throw new IllegalArgumentException("fromKey out of range");
return new DescendingSubMap(m, fromStart, lo, loInclusive, false, fromKey, inclusive);
}


public NavigableMap<K, V> descendingMap() {
NavigableMap<K, V> mv = descendingMapView;
return (mv != null) ? mv
: (descendingMapView = new AscendingSubMap(m, fromStart, lo, loInclusive, toEnd, hi, hiInclusive));
}


Iterator<K> keyIterator() {
return new DescendingSubMapKeyIterator(absHighest(), absLowFence());
}


Iterator<K> descendingKeyIterator() {
return new SubMapKeyIterator(absLowest(), absHighFence());
}


final class DescendingEntrySetView extends EntrySetView {
public Iterator<Map.Entry<K, V>> iterator() {
return new DescendingSubMapEntryIterator(absHighest(), absLowFence());
}
}


public Set<Map.Entry<K, V>> entrySet() {
EntrySetView es = entrySetView;
return (es != null) ? es : new DescendingEntrySetView();
}


TreeMap.Entry<K, V> subLowest() {
return absHighest();
}


TreeMap.Entry<K, V> subHighest() {
return absLowest();
}


TreeMap.Entry<K, V> subCeiling(K key) {
return absFloor(key);
}


TreeMap.Entry<K, V> subHigher(K key) {
return absLower(key);
}


TreeMap.Entry<K, V> subFloor(K key) {
return absCeiling(key);
}


TreeMap.Entry<K, V> subLower(K key) {
return absHigher(key);
}
}


private class SubMap extends AbstractMap<K, V> implements SortedMap<K, V>, java.io.Serializable {
private static final long serialVersionUID = -6520786458950516097L;
private boolean fromStart = false, toEnd = false;
private K fromKey, toKey;


private Object readResolve() {
return new AscendingSubMap(TreeMap.this, fromStart, fromKey, true, toEnd, toKey, false);
}


public Set<Map.Entry<K, V>> entrySet() {
throw new InternalError();
}


public K lastKey() {
throw new InternalError();
}


public K firstKey() {
throw new InternalError();
}


public SortedMap<K, V> subMap(K fromKey, K toKey) {
throw new InternalError();
}


public SortedMap<K, V> headMap(K toKey) {
throw new InternalError();
}


public SortedMap<K, V> tailMap(K fromKey) {
throw new InternalError();
}


public Comparator<? super K> comparator() {
throw new InternalError();
}
}


// Red-black mechanics


private static final boolean RED = false;
private static final boolean BLACK = true;




static final class Entry<K, V> implements Map.Entry<K, V> {
K key;
V value;
Entry<K, V> left = null;
Entry<K, V> right = null;
Entry<K, V> parent;
boolean color = BLACK;


/**
* Make a new cell with given key, value, and parent, and with
* {@code null} child links, and BLACK color.
*/
Entry(K key, V value, Entry<K, V> parent) {
this.key = key;
this.value = value;
this.parent = parent;
}


/**
* Returns the key.
*
* @return the key
*/
public K getKey() {
return key;
}



public V getValue() {
return value;
}



public V setValue(V value) {
V oldValue = this.value;
this.value = value;
return oldValue;
}


public boolean equals(Object o) {
if (!(o instanceof Map.Entry))
return false;
Map.Entry<?, ?> e = (Map.Entry<?, ?>) o;


return valEquals(key, e.getKey()) && valEquals(value, e.getValue());
}


public int hashCode() {
int keyHash = (key == null ? 0 : key.hashCode());
int valueHash = (value == null ? 0 : value.hashCode());
return keyHash ^ valueHash;
}


public String toString() {
return key + "=" + value;
}
}


/**
* Returns the first Entry in the TreeMap (according to the TreeMap's
* key-sort function). Returns null if the TreeMap is empty.
*/
final Entry<K, V> getFirstEntry() {
Entry<K, V> p = root;
if (p != null)
while (p.left != null)
p = p.left;
return p;
}


/**
* Returns the last Entry in the TreeMap (according to the TreeMap's
* key-sort function). Returns null if the TreeMap is empty.
*/
final Entry<K, V> getLastEntry() {
Entry<K, V> p = root;
if (p != null)
while (p.right != null)
p = p.right;
return p;
}


/**
* Returns the successor of the specified Entry, or null if no such.
*/
static <K, V> TreeMap.Entry<K, V> successor(Entry<K, V> t) {
if (t == null)
return null;
else if (t.right != null) {
Entry<K, V> p = t.right;
while (p.left != null)
p = p.left;
return p;
} else {
Entry<K, V> p = t.parent;
Entry<K, V> ch = t;
while (p != null && ch == p.right) {
ch = p;
p = p.parent;
}
return p;
}
}


/**
* Returns the predecessor of the specified Entry, or null if no such.
*/
static <K, V> Entry<K, V> predecessor(Entry<K, V> t) {
if (t == null)
return null;
else if (t.left != null) {
Entry<K, V> p = t.left;
while (p.right != null)
p = p.right;
return p;
} else {
Entry<K, V> p = t.parent;
Entry<K, V> ch = t;
while (p != null && ch == p.left) {
ch = p;
p = p.parent;
}
return p;
}
}




private static <K, V> boolean colorOf(Entry<K, V> p) {
return (p == null ? BLACK : p.color);
}


private static <K, V> Entry<K, V> parentOf(Entry<K, V> p) {
return (p == null ? null : p.parent);
}


private static <K, V> void setColor(Entry<K, V> p, boolean c) {
if (p != null)
p.color = c;
}


private static <K, V> Entry<K, V> leftOf(Entry<K, V> p) {
return (p == null) ? null : p.left;
}


private static <K, V> Entry<K, V> rightOf(Entry<K, V> p) {
return (p == null) ? null : p.right;
}


/** From CLR */
private void rotateLeft(Entry<K, V> p) {
if (p != null) {
Entry<K, V> r = p.right;
p.right = r.left;
if (r.left != null)
r.left.parent = p;
r.parent = p.parent;
if (p.parent == null)
root = r;
else if (p.parent.left == p)
p.parent.left = r;
else
p.parent.right = r;
r.left = p;
p.parent = r;
}
}


/** From CLR */
private void rotateRight(Entry<K, V> p) {
if (p != null) {
Entry<K, V> l = p.left;
p.left = l.right;
if (l.right != null)
l.right.parent = p;
l.parent = p.parent;
if (p.parent == null)
root = l;
else if (p.parent.right == p)
p.parent.right = l;
else
p.parent.left = l;
l.right = p;
p.parent = l;
}
}


/** From CLR */
private void fixAfterInsertion(Entry<K, V> x) {
x.color = RED;


while (x != null && x != root && x.parent.color == RED) {
if (parentOf(x) == leftOf(parentOf(parentOf(x)))) {
Entry<K, V> y = rightOf(parentOf(parentOf(x)));
if (colorOf(y) == RED) {
setColor(parentOf(x), BLACK);
setColor(y, BLACK);
setColor(parentOf(parentOf(x)), RED);
x = parentOf(parentOf(x));
} else {
if (x == rightOf(parentOf(x))) {
x = parentOf(x);
rotateLeft(x);
}
setColor(parentOf(x), BLACK);
setColor(parentOf(parentOf(x)), RED);
rotateRight(parentOf(parentOf(x)));
}
} else {
Entry<K, V> y = leftOf(parentOf(parentOf(x)));
if (colorOf(y) == RED) {
setColor(parentOf(x), BLACK);
setColor(y, BLACK);
setColor(parentOf(parentOf(x)), RED);
x = parentOf(parentOf(x));
} else {
if (x == leftOf(parentOf(x))) {
x = parentOf(x);
rotateRight(x);
}
setColor(parentOf(x), BLACK);
setColor(parentOf(parentOf(x)), RED);
rotateLeft(parentOf(parentOf(x)));
}
}
}
root.color = BLACK;
}


private void deleteEntry(Entry<K, V> p) {
modCount++;
size--;


// If strictly internal, copy successor's element to p and then make p
// point to successor.
if (p.left != null && p.right != null) {
Entry<K, V> s = successor(p);
p.key = s.key;
p.value = s.value;
p = s;
} // p has 2 children


// Start fixup at replacement node, if it exists.
Entry<K, V> replacement = (p.left != null ? p.left : p.right);


if (replacement != null) {
// Link replacement to parent
replacement.parent = p.parent;
if (p.parent == null)
root = replacement;
else if (p == p.parent.left)
p.parent.left = replacement;
else
p.parent.right = replacement;


// Null out links so they are OK to use by fixAfterDeletion.
p.left = p.right = p.parent = null;


// Fix replacement
if (p.color == BLACK)
fixAfterDeletion(replacement);
} else if (p.parent == null) { // return if we are the only node.
root = null;
} else { // No children. Use self as phantom replacement and unlink.
if (p.color == BLACK)
fixAfterDeletion(p);


if (p.parent != null) {
if (p == p.parent.left)
p.parent.left = null;
else if (p == p.parent.right)
p.parent.right = null;
p.parent = null;
}
}
}


/** From CLR */
private void fixAfterDeletion(Entry<K, V> x) {
while (x != root && colorOf(x) == BLACK) {
if (x == leftOf(parentOf(x))) {
Entry<K, V> sib = rightOf(parentOf(x));


if (colorOf(sib) == RED) {
setColor(sib, BLACK);
setColor(parentOf(x), RED);
rotateLeft(parentOf(x));
sib = rightOf(parentOf(x));
}


if (colorOf(leftOf(sib)) == BLACK && colorOf(rightOf(sib)) == BLACK) {
setColor(sib, RED);
x = parentOf(x);
} else {
if (colorOf(rightOf(sib)) == BLACK) {
setColor(leftOf(sib), BLACK);
setColor(sib, RED);
rotateRight(sib);
sib = rightOf(parentOf(x));
}
setColor(sib, colorOf(parentOf(x)));
setColor(parentOf(x), BLACK);
setColor(rightOf(sib), BLACK);
rotateLeft(parentOf(x));
x = root;
}
} else { // symmetric
Entry<K, V> sib = leftOf(parentOf(x));


if (colorOf(sib) == RED) {
setColor(sib, BLACK);
setColor(parentOf(x), RED);
rotateRight(parentOf(x));
sib = leftOf(parentOf(x));
}


if (colorOf(rightOf(sib)) == BLACK && colorOf(leftOf(sib)) == BLACK) {
setColor(sib, RED);
x = parentOf(x);
} else {
if (colorOf(leftOf(sib)) == BLACK) {
setColor(rightOf(sib), BLACK);
setColor(sib, RED);
rotateLeft(sib);
sib = leftOf(parentOf(x));
}
setColor(sib, colorOf(parentOf(x)));
setColor(parentOf(x), BLACK);
setColor(leftOf(sib), BLACK);
rotateRight(parentOf(x));
x = root;
}
}
}


setColor(x, BLACK);
}


private static final long serialVersionUID = 919286545866124006L;


private void writeObject(java.io.ObjectOutputStream s) throws java.io.IOException {
// Write out the Comparator and any hidden stuff
s.defaultWriteObject();


// Write out size (number of Mappings)
s.writeInt(size);


// Write out keys and values (alternating)
for (Iterator<Map.Entry<K, V>> i = entrySet().iterator(); i.hasNext();) {
Map.Entry<K, V> e = i.next();
s.writeObject(e.getKey());
s.writeObject(e.getValue());
}
}


private void readObject(final java.io.ObjectInputStream s) throws java.io.IOException, ClassNotFoundException {
// Read in the Comparator and any hidden stuff
s.defaultReadObject();


// Read in size
int size = s.readInt();


buildFromSorted(size, null, s, null);
}


void readTreeSet(int size, java.io.ObjectInputStream s, V defaultVal)
throws java.io.IOException, ClassNotFoundException {
buildFromSorted(size, null, s, defaultVal);
}


void addAllForTreeSet(SortedSet<? extends K> set, V defaultVal) {
try {
buildFromSorted(set.size(), set.iterator(), null, defaultVal);
} catch (java.io.IOException cannotHappen) {
} catch (ClassNotFoundException cannotHappen) {
}
}




private void buildFromSorted(int size, Iterator it, java.io.ObjectInputStream str, V defaultVal)
throws java.io.IOException, ClassNotFoundException {
this.size = size;
root = buildFromSorted(0, 0, size - 1, computeRedLevel(size), it, str, defaultVal);
}




private final Entry<K, V> buildFromSorted(int level, int lo, int hi, int redLevel, Iterator it,
java.io.ObjectInputStream str, V defaultVal) throws java.io.IOException, ClassNotFoundException {
/*
* Strategy: The root is the middlemost element. To get to it, we have
* to first recursively construct the entire left subtree, so as to grab
* all of its elements. We can then proceed with right subtree.
*
* The lo and hi arguments are the minimum and maximum indices to pull
* out of the iterator or stream for current subtree. They are not
* actually indexed, we just proceed sequentially, ensuring that items
* are extracted in corresponding order.
*/


if (hi < lo)
return null;


int mid = (lo + hi) >>> 1;


Entry<K, V> left = null;
if (lo < mid)
left = buildFromSorted(level + 1, lo, mid - 1, redLevel, it, str, defaultVal);


// extract key and/or value from iterator or stream
K key;
V value;
if (it != null) {
if (defaultVal == null) {
Map.Entry<K, V> entry = (Map.Entry<K, V>) it.next();
key = entry.getKey();
value = entry.getValue();
} else {
key = (K) it.next();
value = defaultVal;
}
} else { // use stream
key = (K) str.readObject();
value = (defaultVal != null ? defaultVal : (V) str.readObject());
}


Entry<K, V> middle = new Entry<>(key, value, null);


// color nodes in non-full bottommost level red
if (level == redLevel)
middle.color = RED;


if (left != null) {
middle.left = left;
left.parent = middle;
}


if (mid < hi) {
Entry<K, V> right = buildFromSorted(level + 1, mid + 1, hi, redLevel, it, str, defaultVal);
middle.right = right;
right.parent = middle;
}


return middle;
}




private static int computeRedLevel(int sz) {
int level = 0;
for (int m = sz - 1; m >= 0; m = m / 2 - 1)
level++;
return level;
}
}