package java.util;
import java.io.IOException;
import java.io.InvalidObjectException;
import java.io.Serializable;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.function.BiConsumer;
import java.util.function.BiFunction;
import java.util.function.Consumer;
import java.util.function.Function;
import sun.misc.SharedSecrets;
//HashMap
//HashMap是 一个桶数组，每一个桶位是链表或者红黑树
//HashMap的一个实例有两个影响其性能的参数： 初始容量和负载因子 。
// 容量是哈希表中的桶数，初始容量只是创建哈希表时的容量。
// 负载因子是在容量自动增加之前允许哈希表得到满足的度量。
// 当在散列表中的条目的数量超过了负载因数和容量的乘积，哈希表被重新散列 （即，内部数据结构被重建），使得哈希表具有桶的大约两倍。
public class HashMap<K, V> extends AbstractMap<K, V>
implements Map<K, V>, Cloneable, Serializable {
private static final long serialVersionUID = 362498820763181265L;
//初始桶容量：必须是2的幂
static final int DEFAULT_INITIAL_CAPACITY = 1 << 4; // aka 16
//最大容量
static final int MAXIMUM_CAPACITY = 1 << 30;
//负载因子
static final float DEFAULT_LOAD_FACTOR = 0.75f;
// 链表节点转换红黑树节点的阈值, 9个节点转
static final int TREEIFY_THRESHOLD = 8;
// 红黑树节点转换链表节点的阈值, 6个节点转
static final int UNTREEIFY_THRESHOLD = 6;
// 转红黑树时, 桶的最小数量
static final int MIN_TREEIFY_CAPACITY = 64;
//HashMap的Node结点
static class Node<K, V> implements Map.Entry<K, V> {
final int hash;
final K key;
V value;
Node<K, V> next;
Node(int hash, K key, V value, Node<K, V> next){
this.hash = hash;
this.key = key;
this.value = value;
this.next = next;
}
public final K getKey(){ return key; }
public final V getValue(){ return value; }
public final String toString(){ return key + "=" + value; }
public final int hashCode(){
return Objects.hashCode(key) ^ Objects.hashCode(value);
}
public final V setValue(V newValue){
V oldValue = value;
value = newValue;
return oldValue;
}
public final boolean equals(Object o){
if(o == this)
return true;
if(o instanceof Map.Entry){
Map.Entry<?, ?> e = (Map.Entry<?, ?>) o;
if(Objects.equals(key, e.getKey()) &&
Objects.equals(value, e.getValue()))
return true;
}
return false;
}
}
/* ---------------- Static utilities -------------- */
//哈希函数，key为null,hash=0，hashcode(地址值) 无符号右移16位再异或运算，也就是高16位不变，低16位与高16位异或
static final int hash(Object key){
int h;
return (key == null) ? 0 : (h = key.hashCode()) ^ (h >>> 16);
}
//内部类，比较器
static Class<?> comparableClassFor(Object x){
if(x instanceof Comparable){
Class<?> c;
Type[] ts, as;
Type t;
ParameterizedType p;
if((c = x.getClass()) == String.class) // bypass checks
return c;
if((ts = c.getGenericInterfaces()) != null){
for(int i = 0; i < ts.length; ++i){
if(((t = ts[i]) instanceof ParameterizedType) &&
((p = (ParameterizedType) t).getRawType() ==
Comparable.class) &&
(as = p.getActualTypeArguments()) != null &&
as.length == 1 && as[0] == c) // type arg is c
return c;
}
}
}
return null;
}
@SuppressWarnings({"rawtypes", "unchecked"}) // for cast to Comparable
static int compareComparables(Class<?> kc, Object k, Object x){
return (x == null || x.getClass() != kc ? 0 :
((Comparable) k).compareTo(x));
}
static final int tableSizeFor(int cap){//大于cap的最小2个整数次幂，从cap第一个高位1开始之后全1
int n = cap - 1;
n |= n >>> 1;
n |= n >>> 2;
n |= n >>> 4;
n |= n >>> 8;
n |= n >>> 16;
return (n < 0) ? 1 : (n >= MAXIMUM_CAPACITY) ? MAXIMUM_CAPACITY : n + 1;
}
/* ---------------- Fields -------------- */
//hash 桶的数量，Node[]数组
transient Node<K, V>[] table;
// 视图，key-vlue构成的set集合
transient Set<Map.Entry<K, V>> entrySet;
//map中的key-value键值对数量
transient int size;
//Hashmap修改次数,用于实现fail-fast策略
//HashMap不是线程安全的，因此如果在使用迭代器的过程中有其他线程修改了map，
//那么将抛出ConcurrentModificationException，这就是所谓fail-fast策略
transient int modCount;
//链表节点转换红黑树节点的阈值
int threshold;
//负载因子
final float loadFactor;
/* ---------------- Public operations -------------- */
//有参构造:容量
public HashMap(int initialCapacity, float loadFactor){
if(initialCapacity < 0)
throw new IllegalArgumentException("Illegal initial capacity: " +
initialCapacity);
if(initialCapacity > MAXIMUM_CAPACITY)
initialCapacity = MAXIMUM_CAPACITY;
if(loadFactor <= 0 || Float.isNaN(loadFactor))
throw new IllegalArgumentException("Illegal load factor: " +
loadFactor);
this.loadFactor = loadFactor;
this.threshold = tableSizeFor(initialCapacity);
}
public HashMap(int initialCapacity){
this(initialCapacity, DEFAULT_LOAD_FACTOR);
}
public HashMap(){
this.loadFactor = DEFAULT_LOAD_FACTOR; // all other fields defaulted
}
public HashMap(Map<? extends K, ? extends V> m){
this.loadFactor = DEFAULT_LOAD_FACTOR;
putMapEntries(m, false);
}
// 有参构造，通过一个map构造new map
final void putMapEntries(Map<? extends K, ? extends V> m, boolean evict){
int s = m.size();
if(s > 0){
if(table == null){ // pre-size
float ft = ((float) s / loadFactor) + 1.0F;
int t = ((ft < (float) MAXIMUM_CAPACITY) ?
(int) ft : MAXIMUM_CAPACITY);
if(t > threshold)
threshold = tableSizeFor(t);
}else if(s > threshold)
resize();
for(Map.Entry<? extends K, ? extends V> e : m.entrySet()){
K key = e.getKey();
V value = e.getValue();
putVal(hash(key), key, value, false, evict);
}
}
}
public int size(){
return size;
}
public boolean isEmpty(){
return size == 0;
}
public V get(Object key){
Node<K, V> e;
return (e = getNode(hash(key), key)) == null ? null : e.value;
}
//通过hash值和key值获取Node
final Node<K, V> getNode(int hash, Object key){
Node<K, V>[] tab;
Node<K, V> first, e;
int n;//n为2的幂100，n-1表达的意义是低位全1，(n-1)&hash 二进制的模运算
K k;
if((tab = table) != null && (n = tab.length) > 0 &&
(first = tab[(n - 1) & hash]) != null){
if(first.hash == hash && // always check first node
((k = first.key) == key || (key != null && key.equals(k))))
return first; //桶中的第一个元素
if((e = first.next) != null){
if(first instanceof TreeNode) //是TreeNode红黑树节点，通过红黑树的查询方法
return ((TreeNode<K, V>) first).getTreeNode(hash, key);
do { //桶中是链表结构，从first往后遍历查询
if(e.hash == hash &&
((k = e.key) == key || (key != null && key.equals(k))))
return e;
} while ((e = e.next) != null);
}
}
return null;
}
//判断是否包含key,通过getNode方法实现
public boolean containsKey(Object key){
return getNode(hash(key), key) != null;
}
//通过putVal实现
public V put(K key, V value){
return putVal(hash(key), key, value, false, true);
}
//添加键值对到map中
final V putVal(int hash, K key, V value, boolean onlyIfAbsent,
boolean evict){
Node<K, V>[] tab; //table
Node<K, V> p;
int n, i;
if((tab = table) == null || (n = tab.length) == 0)
n = (tab = resize()).length;
if((p = tab[i = (n - 1) & hash]) == null) //如果这个node(桶位空着)不存在，直接添加
tab[i] = newNode(hash, key, value, null);
else{
Node<K, V> e;
K k;
if(p.hash == hash &&
((k = p.key) == key || (key != null && key.equals(k)))) //key与first相等，直接修改
e = p;
else if(p instanceof TreeNode) //判断这个桶中是否是红黑树
e = ((TreeNode<K, V>) p).putTreeVal(this, tab, hash, key, value);
else{//桶中是链表，遍历查找key
for(int binCount = 0; ; ++binCount){
if((e = p.next) == null){
p.next = newNode(hash, key, value, null);
if(binCount >= TREEIFY_THRESHOLD - 1) // -1 for 1st
treeifyBin(tab, hash);
break;
}
if(e.hash == hash &&
((k = e.key) == key || (key != null && key.equals(k))))
break;
p = e;
}
}
if(e != null){ // existing mapping for key
V oldValue = e.value;
if(!onlyIfAbsent || oldValue == null)
e.value = value;
afterNodeAccess(e);
return oldValue;
}
}
++modCount;
if(++size > threshold)
resize();
afterNodeInsertion(evict);
return null;
}
// 桶数组扩容，扩容为2倍
final Node<K, V>[] resize(){
Node<K, V>[] oldTab = table;
int oldCap = (oldTab == null) ? 0 : oldTab.length;
int oldThr = threshold;
int newCap, newThr = 0;
if(oldCap > 0){
if(oldCap >= MAXIMUM_CAPACITY){
threshold = Integer.MAX_VALUE;
return oldTab;
}else if((newCap = oldCap << 1) < MAXIMUM_CAPACITY &&
oldCap >= DEFAULT_INITIAL_CAPACITY)
newThr = oldThr << 1; // double threshold
}else if(oldThr > 0) // initial capacity was placed in threshold
newCap = oldThr;
else{ // zero initial threshold signifies using defaults
newCap = DEFAULT_INITIAL_CAPACITY;
newThr = (int) (DEFAULT_LOAD_FACTOR * DEFAULT_INITIAL_CAPACITY);
}
if(newThr == 0){
float ft = (float) newCap * loadFactor;
newThr = (newCap < MAXIMUM_CAPACITY && ft < (float) MAXIMUM_CAPACITY ?
(int) ft : Integer.MAX_VALUE);
}
threshold = newThr;
@SuppressWarnings({"rawtypes", "unchecked"})
Node<K, V>[] newTab = (Node<K, V>[]) new Node[newCap];
table = newTab;
if(oldTab != null){
for(int j = 0; j < oldCap; ++j){
Node<K, V> e;
if((e = oldTab[j]) != null){ //桶位非null
oldTab[j] = null;
if(e.next == null) //桶位只有一个元素
newTab[e.hash & (newCap - 1)] = e;
else if(e instanceof TreeNode) //桶内是红黑树
((TreeNode<K, V>) e).split(this, newTab, j, oldCap);
else{ // preserve order //桶内是链表
Node<K, V> loHead = null, loTail = null;
Node<K, V> hiHead = null, hiTail = null;
Node<K, V> next;
do {
next = e.next;
if((e.hash & oldCap) == 0){
if(loTail == null)
loHead = e;
else
loTail.next = e;
loTail = e;
}else{
if(hiTail == null)
hiHead = e;
else
hiTail.next = e;
hiTail = e;
}
} while ((e = next) != null);
if(loTail != null){
loTail.next = null;
newTab[j] = loHead;
}
if(hiTail != null){
hiTail.next = null;
newTab[j + oldCap] = hiHead;
}
}
}
}
}
return newTab;
}
//替换给定哈希的索引处（桶数组)的所有链接节点
final void treeifyBin(Node<K, V>[] tab, int hash){
int n, index;
Node<K, V> e;
if(tab == null || (n = tab.length) < MIN_TREEIFY_CAPACITY)
resize();
else if((e = tab[index = (n - 1) & hash]) != null){
TreeNode<K, V> hd = null, tl = null;
do {
TreeNode<K, V> p = replacementTreeNode(e, null);
if(tl == null)
hd = p;
else{
p.prev = tl;
tl.next = p;
}
tl = p;
} while ((e = e.next) != null);
if((tab[index] = hd) != null)
hd.treeify(tab);
}
}
public void putAll(Map<? extends K, ? extends V> m){
putMapEntries(m, true);
}
//移除指定key-value,调用removeNode实现
public V remove(Object key){
Node<K, V> e;
return (e = removeNode(hash(key), key, null, false, true)) == null ?
null : e.value;
}
final Node<K, V> removeNode(int hash, Object key, Object value,
boolean matchValue, boolean movable){
Node<K, V>[] tab;
Node<K, V> p;
int n, index;
if((tab = table) != null && (n = tab.length) > 0 &&
(p = tab[index = (n - 1) & hash]) != null){
Node<K, V> node = null, e;
K k;
V v;
if(p.hash == hash &&
((k = p.key) == key || (key != null && key.equals(k))))
node = p;
else if((e = p.next) != null){ //p.next非null,当前桶位是链表或者红黑树
if(p instanceof TreeNode)//红黑树
node = ((TreeNode<K, V>) p).getTreeNode(hash, key);
else{ //链表
do {
if(e.hash == hash &&
((k = e.key) == key ||
(key != null && key.equals(k)))){
node = e;
break;
}
p = e;
} while ((e = e.next) != null);
}
}
if(node != null && (!matchValue || (v = node.value) == value ||
(value != null && value.equals(v)))){
if(node instanceof TreeNode)
((TreeNode<K, V>) node).removeTreeNode(this, tab, movable);
else if(node == p)
tab[index] = node.next;
else
p.next = node.next;
++modCount;
--size;
afterNodeRemoval(node);
return node;
}
}
return null;
}
//全部null,通过GC回收
public void clear(){
Node<K, V>[] tab;
modCount++;
if((tab = table) != null && size > 0){
size = 0;
for(int i = 0; i < tab.length; ++i){ tab[i] = null; }
}
}
//判断value是否存在，遍历桶数组，再遍历桶位每一个元素，再比较value
public boolean containsValue(Object value){
Node<K, V>[] tab;
V v;
if((tab = table) != null && size > 0){
for(int i = 0; i < tab.length; ++i){
for(Node<K, V> e = tab[i]; e != null; e = e.next){
if((v = e.value) == value ||
(value != null && value.equals(v)))
return true;
}
}
}
return false;
}
//通过内部类KeySet实现
public Set<K> keySet(){
Set<K> ks = keySet;
if(ks == null){
ks = new KeySet();
keySet = ks;
}
return ks;
}
final class KeySet extends AbstractSet<K> {
public final int size(){ return size; }
public final void clear(){ HashMap.this.clear(); }
public final Iterator<K> iterator(){ return new KeyIterator(); }
public final boolean contains(Object o){ return containsKey(o); }
public final boolean remove(Object key){
return removeNode(hash(key), key, null, false, true) != null;
}
public final Spliterator<K> spliterator(){
return new KeySpliterator<>(HashMap.this, 0, -1, 0, 0);
}
public final void forEach(Consumer<? super K> action){
Node<K, V>[] tab;
if(action == null)
throw new NullPointerException();
if(size > 0 && (tab = table) != null){
int mc = modCount;
for(int i = 0; i < tab.length; ++i){
for(Node<K, V> e = tab[i]; e != null; e = e.next){ action.accept(e.key); }
}
if(modCount != mc)
throw new ConcurrentModificationException();
}
}
}
// 全体values构成容器，通过内部类Values实现
public Collection<V> values(){
Collection<V> vs = values;
if(vs == null){
vs = new Values();
values = vs;
}
return vs;
}
final class Values extends AbstractCollection<V> {
public final int size(){ return size; }
public final void clear(){ HashMap.this.clear(); }
public final Iterator<V> iterator(){ return new ValueIterator(); }
public final boolean contains(Object o){ return containsValue(o); }
public final Spliterator<V> spliterator(){
return new ValueSpliterator<>(HashMap.this, 0, -1, 0, 0);
}
public final void forEach(Consumer<? super V> action){
Node<K, V>[] tab;
if(action == null)
throw new NullPointerException();
if(size > 0 && (tab = table) != null){
int mc = modCount;
for(int i = 0; i < tab.length; ++i){
for(Node<K, V> e = tab[i]; e != null; e = e.next){ action.accept(e.value); }
}
if(modCount != mc)
throw new ConcurrentModificationException();
}
}
}
// 全体key-value构成的Set集合，通过内部类
public Set<Map.Entry<K, V>> entrySet(){
Set<Map.Entry<K, V>> es;
return (es = entrySet) == null ? (entrySet = new EntrySet()) : es;
}
final class EntrySet extends AbstractSet<Map.Entry<K, V>> {
public final int size(){ return size; }
public final void clear(){ HashMap.this.clear(); }
public final Iterator<Map.Entry<K, V>> iterator(){
return new EntryIterator();
}
public final boolean contains(Object o){
if(!(o instanceof Map.Entry))
return false;
Map.Entry<?, ?> e = (Map.Entry<?, ?>) o;
Object key = e.getKey();
Node<K, V> candidate = getNode(hash(key), key);
return candidate != null && candidate.equals(e);
}
public final boolean remove(Object o){
if(o instanceof Map.Entry){
Map.Entry<?, ?> e = (Map.Entry<?, ?>) o;
Object key = e.getKey();
Object value = e.getValue();
return removeNode(hash(key), key, value, true, true) != null;
}
return false;
}
public final Spliterator<Map.Entry<K, V>> spliterator(){
return new EntrySpliterator<>(HashMap.this, 0, -1, 0, 0);
}
public final void forEach(Consumer<? super Map.Entry<K, V>> action){
Node<K, V>[] tab;
if(action == null)
throw new NullPointerException();
if(size > 0 && (tab = table) != null){
int mc = modCount;
for(int i = 0; i < tab.length; ++i){
for(Node<K, V> e = tab[i]; e != null; e = e.next){ action.accept(e); }
}
if(modCount != mc)
throw new ConcurrentModificationException();
}
}
}
// Overrides of JDK8 Map extension methods
//如果key存在，返回对应的value,否则返回defaultValue
@Override
public V getOrDefault(Object key, V defaultValue){
Node<K, V> e;
return (e = getNode(hash(key), key)) == null ? defaultValue : e.value;
}
@Override
public V putIfAbsent(K key, V value){
return putVal(hash(key), key, value, true, true);
}
@Override
public boolean remove(Object key, Object value){
return removeNode(hash(key), key, value, true, true) != null;
}
@Override
public boolean replace(K key, V oldValue, V newValue){
Node<K, V> e;
V v;
if((e = getNode(hash(key), key)) != null &&
((v = e.value) == oldValue || (v != null && v.equals(oldValue)))){
e.value = newValue;
afterNodeAccess(e);
return true;
}
return false;
}
@Override
public V replace(K key, V value){
Node<K, V> e;
if((e = getNode(hash(key), key)) != null){
V oldValue = e.value;
e.value = value;
afterNodeAccess(e);
return oldValue;
}
return null;
}
@Override
public V computeIfAbsent(K key,
Function<? super K, ? extends V> mappingFunction){
if(mappingFunction == null)
throw new NullPointerException();
int hash = hash(key);
Node<K, V>[] tab;
Node<K, V> first;
int n, i;
int binCount = 0;
TreeNode<K, V> t = null;
Node<K, V> old = null;
if(size > threshold || (tab = table) == null ||
(n = tab.length) == 0)
n = (tab = resize()).length;
if((first = tab[i = (n - 1) & hash]) != null){
if(first instanceof TreeNode)
old = (t = (TreeNode<K, V>) first).getTreeNode(hash, key);
else{
Node<K, V> e = first;
K k;
do {
if(e.hash == hash &&
((k = e.key) == key || (key != null && key.equals(k)))){
old = e;
break;
}
++binCount;
} while ((e = e.next) != null);
}
V oldValue;
if(old != null && (oldValue = old.value) != null){
afterNodeAccess(old);
return oldValue;
}
}
V v = mappingFunction.apply(key);
if(v == null){
return null;
}else if(old != null){
old.value = v;
afterNodeAccess(old);
return v;
}else if(t != null)
t.putTreeVal(this, tab, hash, key, v);
else{
tab[i] = newNode(hash, key, v, first);
if(binCount >= TREEIFY_THRESHOLD - 1)
treeifyBin(tab, hash);
}
++modCount;
++size;
afterNodeInsertion(true);
return v;
}
public V computeIfPresent(K key,
BiFunction<? super K, ? super V, ? extends V> remappingFunction){
if(remappingFunction == null)
throw new NullPointerException();
Node<K, V> e;
V oldValue;
int hash = hash(key);
if((e = getNode(hash, key)) != null &&
(oldValue = e.value) != null){
V v = remappingFunction.apply(key, oldValue);
if(v != null){
e.value = v;
afterNodeAccess(e);
return v;
}else
removeNode(hash, key, null, false, true);
}
return null;
}
@Override
public V compute(K key,
BiFunction<? super K, ? super V, ? extends V> remappingFunction){
if(remappingFunction == null)
throw new NullPointerException();
int hash = hash(key);
Node<K, V>[] tab;
Node<K, V> first;
int n, i;
int binCount = 0;
TreeNode<K, V> t = null;
Node<K, V> old = null;
if(size > threshold || (tab = table) == null ||
(n = tab.length) == 0)
n = (tab = resize()).length;
if((first = tab[i = (n - 1) & hash]) != null){
if(first instanceof TreeNode)
old = (t = (TreeNode<K, V>) first).getTreeNode(hash, key);
else{
Node<K, V> e = first;
K k;
do {
if(e.hash == hash &&
((k = e.key) == key || (key != null && key.equals(k)))){
old = e;
break;
}
++binCount;
} while ((e = e.next) != null);
}
}
V oldValue = (old == null) ? null : old.value;
V v = remappingFunction.apply(key, oldValue);
if(old != null){
if(v != null){
old.value = v;
afterNodeAccess(old);
}else
removeNode(hash, key, null, false, true);
}else if(v != null){
if(t != null)
t.putTreeVal(this, tab, hash, key, v);
else{
tab[i] = newNode(hash, key, v, first);
if(binCount >= TREEIFY_THRESHOLD - 1)
treeifyBin(tab, hash);
}
++modCount;
++size;
afterNodeInsertion(true);
}
return v;
}
@Override
public V merge(K key, V value,
BiFunction<? super V, ? super V, ? extends V> remappingFunction){
if(value == null)
throw new NullPointerException();
if(remappingFunction == null)
throw new NullPointerException();
int hash = hash(key);
Node<K, V>[] tab;
Node<K, V> first;
int n, i;
int binCount = 0;
TreeNode<K, V> t = null;
Node<K, V> old = null;
if(size > threshold || (tab = table) == null ||
(n = tab.length) == 0)
n = (tab = resize()).length;
if((first = tab[i = (n - 1) & hash]) != null){
if(first instanceof TreeNode)
old = (t = (TreeNode<K, V>) first).getTreeNode(hash, key);
else{
Node<K, V> e = first;
K k;
do {
if(e.hash == hash &&
((k = e.key) == key || (key != null && key.equals(k)))){
old = e;
break;
}
++binCount;
} while ((e = e.next) != null);
}
}
if(old != null){
V v;
if(old.value != null)
v = remappingFunction.apply(old.value, value);
else
v = value;
if(v != null){
old.value = v;
afterNodeAccess(old);
}else
removeNode(hash, key, null, false, true);
return v;
}
if(value != null){
if(t != null)
t.putTreeVal(this, tab, hash, key, value);
else{
tab[i] = newNode(hash, key, value, first);
if(binCount >= TREEIFY_THRESHOLD - 1)
treeifyBin(tab, hash);
}
++modCount;
++size;
afterNodeInsertion(true);
}
return value;
}
@Override
public void forEach(BiConsumer<? super K, ? super V> action){
Node<K, V>[] tab;
if(action == null)
throw new NullPointerException();
if(size > 0 && (tab = table) != null){
int mc = modCount;
for(int i = 0; i < tab.length; ++i){
for(Node<K, V> e = tab[i]; e != null; e = e.next){ action.accept(e.key, e.value); }
}
if(modCount != mc)
throw new ConcurrentModificationException();
}
}
@Override
public void replaceAll(BiFunction<? super K, ? super V, ? extends V> function){
Node<K, V>[] tab;
if(function == null)
throw new NullPointerException();
if(size > 0 && (tab = table) != null){
int mc = modCount;
for(int i = 0; i < tab.length; ++i){
for(Node<K, V> e = tab[i]; e != null; e = e.next){
e.value = function.apply(e.key, e.value);
}
}
if(modCount != mc)
throw new ConcurrentModificationException();
}
}
/* ------------------------------------------------------------ */
// Cloning and serialization
@SuppressWarnings("unchecked")
@Override
public Object clone(){
HashMap<K, V> result;
try {
result = (HashMap<K, V>) super.clone();
} catch (CloneNotSupportedException e) {
// this shouldn't happen, since we are Cloneable
throw new InternalError(e);
}
result.reinitialize();
result.putMapEntries(this, false);
return result;
}
final float loadFactor(){ return loadFactor; }
final int capacity(){
return (table != null) ? table.length :
(threshold > 0) ? threshold :
DEFAULT_INITIAL_CAPACITY;
}
private void writeObject(java.io.ObjectOutputStream s)
throws IOException{
int buckets = capacity();
// Write out the threshold, loadfactor, and any hidden stuff
s.defaultWriteObject();
s.writeInt(buckets);
s.writeInt(size);
internalWriteEntries(s);
}
private void readObject(java.io.ObjectInputStream s)
throws IOException, ClassNotFoundException{
// Read in the threshold (ignored), loadfactor, and any hidden stuff
s.defaultReadObject();
reinitialize();
if(loadFactor <= 0 || Float.isNaN(loadFactor))
throw new InvalidObjectException("Illegal load factor: " +
loadFactor);
s.readInt(); // Read and ignore number of buckets
int mappings = s.readInt(); // Read number of mappings (size)
if(mappings < 0)
throw new InvalidObjectException("Illegal mappings count: " +
mappings);
else if(mappings > 0){ // (if zero, use defaults)
// Size the table using given load factor only if within
// range of 0.25...4.0
float lf = Math.min(Math.max(0.25f, loadFactor), 4.0f);
float fc = (float) mappings / lf + 1.0f;
int cap = ((fc < DEFAULT_INITIAL_CAPACITY) ?
DEFAULT_INITIAL_CAPACITY :
(fc >= MAXIMUM_CAPACITY) ?
MAXIMUM_CAPACITY :
tableSizeFor((int) fc));
float ft = (float) cap * lf;
threshold = ((cap < MAXIMUM_CAPACITY && ft < MAXIMUM_CAPACITY) ?
(int) ft : Integer.MAX_VALUE);
// Check Map.Entry[].class since it's the nearest public type to
// what we're actually creating.
SharedSecrets.getJavaOISAccess().checkArray(s, Map.Entry[].class, cap);
@SuppressWarnings({"rawtypes", "unchecked"})
Node<K, V>[] tab = (Node<K, V>[]) new Node[cap];
table = tab;
// Read the keys and values, and put the mappings in the HashMap
for(int i = 0; i < mappings; i++){
@SuppressWarnings("unchecked")
K key = (K) s.readObject();
@SuppressWarnings("unchecked")
V value = (V) s.readObject();
putVal(hash(key), key, value, false, false);
}
}
}
abstract class HashIterator {
Node<K, V> next; // next entry to return
Node<K, V> current; // current entry
int expectedModCount; // for fast-fail
int index; // current slot
HashIterator(){
expectedModCount = modCount;
Node<K, V>[] t = table;
current = next = null;
index = 0;
if(t != null && size > 0){ // advance to first entry
do {} while (index < t.length && (next = t[index++]) == null);
}
}
public final boolean hasNext(){
return next != null;
}
final Node<K, V> nextNode(){
Node<K, V>[] t;
Node<K, V> e = next;
if(modCount != expectedModCount)
throw new ConcurrentModificationException();
if(e == null)
throw new NoSuchElementException();
if((next = (current = e).next) == null && (t = table) != null){
do {} while (index < t.length && (next = t[index++]) == null);
}
return e;
}
public final void remove(){
Node<K, V> p = current;
if(p == null)
throw new IllegalStateException();
if(modCount != expectedModCount)
throw new ConcurrentModificationException();
current = null;
K key = p.key;
removeNode(hash(key), key, null, false, false);
expectedModCount = modCount;
}
}
final class KeyIterator extends HashIterator
implements Iterator<K> {
public final K next(){ return nextNode().key; }
}
final class ValueIterator extends HashIterator
implements Iterator<V> {
public final V next(){ return nextNode().value; }
}
final class EntryIterator extends HashIterator
implements Iterator<Map.Entry<K, V>> {
public final Map.Entry<K, V> next(){ return nextNode(); }
}
/* ------------------------------------------------------------ */
// spliterators
static class HashMapSpliterator<K, V> {
final HashMap<K, V> map;
Node<K, V> current; // current node
int index; // current index, modified on advance/split
int fence; // one past last index
int est; // size estimate
int expectedModCount; // for comodification checks
HashMapSpliterator(HashMap<K, V> m, int origin,
int fence, int est,
int expectedModCount){
this.map = m;
this.index = origin;
this.fence = fence;
this.est = est;
this.expectedModCount = expectedModCount;
}
final int getFence(){ // initialize fence and size on first use
int hi;
if((hi = fence) < 0){
HashMap<K, V> m = map;
est = m.size;
expectedModCount = m.modCount;
Node<K, V>[] tab = m.table;
hi = fence = (tab == null) ? 0 : tab.length;
}
return hi;
}
public final long estimateSize(){
getFence(); // force init
return (long) est;
}
}
static final class KeySpliterator<K, V>
extends HashMapSpliterator<K, V>
implements Spliterator<K> {
KeySpliterator(HashMap<K, V> m, int origin, int fence, int est,
int expectedModCount){
super(m, origin, fence, est, expectedModCount);
}
public KeySpliterator<K, V> trySplit(){
int hi = getFence(), lo = index, mid = (lo + hi) >>> 1;
return (lo >= mid || current != null) ? null :
new KeySpliterator<>(map, lo, index = mid, est >>>= 1,
expectedModCount);
}
public void forEachRemaining(Consumer<? super K> action){
int i, hi, mc;
if(action == null)
throw new NullPointerException();
HashMap<K, V> m = map;
Node<K, V>[] tab = m.table;
if((hi = fence) < 0){
mc = expectedModCount = m.modCount;
hi = fence = (tab == null) ? 0 : tab.length;
}else
mc = expectedModCount;
if(tab != null && tab.length >= hi &&
(i = index) >= 0 && (i < (index = hi) || current != null)){
Node<K, V> p = current;
current = null;
do {
if(p == null)
p = tab[i++];
else{
action.accept(p.key);
p = p.next;
}
} while (p != null || i < hi);
if(m.modCount != mc)
throw new ConcurrentModificationException();
}
}
public boolean tryAdvance(Consumer<? super K> action){
int hi;
if(action == null)
throw new NullPointerException();
Node<K, V>[] tab = map.table;
if(tab != null && tab.length >= (hi = getFence()) && index >= 0){
while (current != null || index < hi) {
if(current == null)
current = tab[index++];
else{
K k = current.key;
current = current.next;
action.accept(k);
if(map.modCount != expectedModCount)
throw new ConcurrentModificationException();
return true;
}
}
}
return false;
}
public int characteristics(){
return (fence < 0 || est == map.size ? Spliterator.SIZED : 0) |
Spliterator.DISTINCT;
}
}
static final class ValueSpliterator<K, V>
extends HashMapSpliterator<K, V>
implements Spliterator<V> {
ValueSpliterator(HashMap<K, V> m, int origin, int fence, int est,
int expectedModCount){
super(m, origin, fence, est, expectedModCount);
}
public ValueSpliterator<K, V> trySplit(){
int hi = getFence(), lo = index, mid = (lo + hi) >>> 1;
return (lo >= mid || current != null) ? null :
new ValueSpliterator<>(map, lo, index = mid, est >>>= 1,
expectedModCount);
}
public void forEachRemaining(Consumer<? super V> action){
int i, hi, mc;
if(action == null)
throw new NullPointerException();
HashMap<K, V> m = map;
Node<K, V>[] tab = m.table;
if((hi = fence) < 0){
mc = expectedModCount = m.modCount;
hi = fence = (tab == null) ? 0 : tab.length;
}else
mc = expectedModCount;
if(tab != null && tab.length >= hi &&
(i = index) >= 0 && (i < (index = hi) || current != null)){
Node<K, V> p = current;
current = null;
do {
if(p == null)
p = tab[i++];
else{
action.accept(p.value);
p = p.next;
}
} while (p != null || i < hi);
if(m.modCount != mc)
throw new ConcurrentModificationException();
}
}
public boolean tryAdvance(Consumer<? super V> action){
int hi;
if(action == null)
throw new NullPointerException();
Node<K, V>[] tab = map.table;
if(tab != null && tab.length >= (hi = getFence()) && index >= 0){
while (current != null || index < hi) {
if(current == null)
current = tab[index++];
else{
V v = current.value;
current = current.next;
action.accept(v);
if(map.modCount != expectedModCount)
throw new ConcurrentModificationException();
return true;
}
}
}
return false;
}
public int characteristics(){
return (fence < 0 || est == map.size ? Spliterator.SIZED : 0);
}
}
static final class EntrySpliterator<K, V>
extends HashMapSpliterator<K, V>
implements Spliterator<Map.Entry<K, V>> {
EntrySpliterator(HashMap<K, V> m, int origin, int fence, int est,
int expectedModCount){
super(m, origin, fence, est, expectedModCount);
}
public EntrySpliterator<K, V> trySplit(){
int hi = getFence(), lo = index, mid = (lo + hi) >>> 1;
return (lo >= mid || current != null) ? null :
new EntrySpliterator<>(map, lo, index = mid, est >>>= 1,
expectedModCount);
}
public void forEachRemaining(Consumer<? super Map.Entry<K, V>> action){
int i, hi, mc;
if(action == null)
throw new NullPointerException();
HashMap<K, V> m = map;
Node<K, V>[] tab = m.table;
if((hi = fence) < 0){
mc = expectedModCount = m.modCount;
hi = fence = (tab == null) ? 0 : tab.length;
}else
mc = expectedModCount;
if(tab != null && tab.length >= hi &&
(i = index) >= 0 && (i < (index = hi) || current != null)){
Node<K, V> p = current;
current = null;
do {
if(p == null)
p = tab[i++];
else{
action.accept(p);
p = p.next;
}
} while (p != null || i < hi);
if(m.modCount != mc)
throw new ConcurrentModificationException();
}
}
public boolean tryAdvance(Consumer<? super Map.Entry<K, V>> action){
int hi;
if(action == null)
throw new NullPointerException();
Node<K, V>[] tab = map.table;
if(tab != null && tab.length >= (hi = getFence()) && index >= 0){
while (current != null || index < hi) {
if(current == null)
current = tab[index++];
else{
Node<K, V> e = current;
current = current.next;
action.accept(e);
if(map.modCount != expectedModCount)
throw new ConcurrentModificationException();
return true;
}
}
}
return false;
}
public int characteristics(){
return (fence < 0 || est == map.size ? Spliterator.SIZED : 0) |
Spliterator.DISTINCT;
}
}
/* ------------------------------------------------------------ */
// LinkedHashMap support
// 创建一个链表Node
Node<K, V> newNode(int hash, K key, V value, Node<K, V> next){
return new Node<>(hash, key, value, next);
}
// 将红黑树Node转换为链表Node
Node<K, V> replacementNode(Node<K, V> p, Node<K, V> next){
return new Node<>(p.hash, p.key, p.value, next);
}
// 创建一个红黑树Node
TreeNode<K, V> newTreeNode(int hash, K key, V value, Node<K, V> next){
return new TreeNode<>(hash, key, value, next);
}
// For treeifyBin
TreeNode<K, V> replacementTreeNode(Node<K, V> p, Node<K, V> next){
return new TreeNode<>(p.hash, p.key, p.value, next);
}
/**
* Reset to initial default state. Called by clone and readObject.
*/
void reinitialize(){
table = null;
entrySet = null;
keySet = null;
values = null;
modCount = 0;
threshold = 0;
size = 0;
}
// Callbacks to allow LinkedHashMap post-actions
void afterNodeAccess(Node<K, V> p){ }
void afterNodeInsertion(boolean evict){ }
void afterNodeRemoval(Node<K, V> p){ }
// Called only from writeObject, to ensure compatible ordering.
void internalWriteEntries(java.io.ObjectOutputStream s) throws IOException{
Node<K, V>[] tab;
if(size > 0 && (tab = table) != null){
for(int i = 0; i < tab.length; ++i){
for(Node<K, V> e = tab[i]; e != null; e = e.next){
s.writeObject(e.key);
s.writeObject(e.value);
}
}
}
}
/* ------------------------------------------------------------ */
// Tree bins
//红黑树,红黑树的头结点为：桶数组[hash(key)]
static final class TreeNode<K, V> extends LinkedHashMap.Entry<K, V> {
TreeNode<K, V> parent; // red-black tree links
TreeNode<K, V> left;
TreeNode<K, V> right;
TreeNode<K, V> prev; // needed to unlink next upon deletion
boolean red;
TreeNode(int hash, K key, V val, Node<K, V> next){
super(hash, key, val, next);
}
//查找当前红黑树的根结点
final TreeNode<K, V> root(){
for(TreeNode<K, V> r = this, p; ; ){
if((p = r.parent) == null)
return r;
r = p;
}
}
//保证给定root结点是 桶数组桶位的first结点
static <K, V> void moveRootToFront(Node<K, V>[] tab, TreeNode<K, V> root){
int n;
if(root != null && tab != null && (n = tab.length) > 0){
int index = (n - 1) & root.hash;
TreeNode<K, V> first = (TreeNode<K, V>) tab[index];
if(root != first){
Node<K, V> rn;
tab[index] = root;
TreeNode<K, V> rp = root.prev;
if((rn = root.next) != null)
((TreeNode<K, V>) rn).prev = rp;
if(rp != null)
rp.next = rn;
if(first != null)
first.prev = root;
root.next = first;
root.prev = null;
}
assert checkInvariants(root);
}
}
/**
* Finds the node starting at root p with the given hash and key.
* The kc argument caches comparableClassFor(key) upon first u***paring keys.
*/
final TreeNode<K, V> find(int h, Object k, Class<?> kc){
TreeNode<K, V> p = this;
do {
int ph, dir;
K pk;
TreeNode<K, V> pl = p.left, pr = p.right, q;
if((ph = p.hash) > h)
p = pl;
else if(ph < h)
p = pr;
else if((pk = p.key) == k || (k != null && k.equals(pk)))
return p;
else if(pl == null)
p = pr;
else if(pr == null)
p = pl;
else if((kc != null ||
(kc = comparableClassFor(k)) != null) &&
(dir = compareComparables(kc, k, pk)) != 0)
p = (dir < 0) ? pl : pr;
else if((q = pr.find(h, k, kc)) != null)
return q;
else
p = pl;
} while (p != null);
return null;
}
/**
* Calls find for root node.
*/
final TreeNode<K, V> getTreeNode(int h, Object k){
return ((parent != null) ? root() : this).find(h, k, null);
}
/**
* Tie-breaking utility for ordering insertions when equal
* hashCodes and non-comparable. We don't require a total
* order, just a consistent insertion rule to maintain
* equivalence across rebalancings. Tie-breaking further than
* necessary simplifies testing a bit.
*/
static int tieBreakOrder(Object a, Object b){
int d;
if(a == null || b == null ||
(d = a.getClass().getName().
compareTo(b.getClass().getName())) == 0)
d = (System.identityHashCode(a) <= System.identityHashCode(b) ?
-1 : 1);
return d;
}
/**
* Forms tree of the nodes linked from this node.
*/
final void treeify(Node<K, V>[] tab){
TreeNode<K, V> root = null;
for(TreeNode<K, V> x = this, next; x != null; x = next){
next = (TreeNode<K, V>) x.next;
x.left = x.right = null;
if(root == null){
x.parent = null;
x.red = false;
root = x;
}else{
K k = x.key;
int h = x.hash;
Class<?> kc = null;
for(TreeNode<K, V> p = root; ; ){
int dir, ph;
K pk = p.key;
if((ph = p.hash) > h)
dir = -1;
else if(ph < h)
dir = 1;
else if((kc == null &&
(kc = comparableClassFor(k)) == null) ||
(dir = compareComparables(kc, k, pk)) == 0)
dir = tieBreakOrder(k, pk);
TreeNode<K, V> xp = p;
if((p = (dir <= 0) ? p.left : p.right) == null){
x.parent = xp;
if(dir <= 0)
xp.left = x;
else
xp.right = x;
root = balanceInsertion(root, x);
break;
}
}
}
}
moveRootToFront(tab, root);
}
/**
* Returns a list of non-TreeNodes replacing those linked from
* this node.
*/
final Node<K, V> untreeify(HashMap<K, V> map){
Node<K, V> hd = null, tl = null;
for(Node<K, V> q = this; q != null; q = q.next){
Node<K, V> p = map.replacementNode(q, null);
if(tl == null)
hd = p;
else
tl.next = p;
tl = p;
}
return hd;
}
/**
* Tree version of putVal.
*/
final TreeNode<K, V> putTreeVal(HashMap<K, V> map, Node<K, V>[] tab,
int h, K k, V v){
Class<?> kc = null;
boolean searched = false;
TreeNode<K, V> root = (parent != null) ? root() : this;
for(TreeNode<K, V> p = root; ; ){
int dir, ph;
K pk;
if((ph = p.hash) > h)
dir = -1;
else if(ph < h)
dir = 1;
else if((pk = p.key) == k || (k != null && k.equals(pk)))
return p;
else if((kc == null &&
(kc = comparableClassFor(k)) == null) ||
(dir = compareComparables(kc, k, pk)) == 0){
if(!searched){
TreeNode<K, V> q, ch;
searched = true;
if(((ch = p.left) != null &&
(q = ch.find(h, k, kc)) != null) ||
((ch = p.right) != null &&
(q = ch.find(h, k, kc)) != null))
return q;
}
dir = tieBreakOrder(k, pk);
}
TreeNode<K, V> xp = p;
if((p = (dir <= 0) ? p.left : p.right) == null){
Node<K, V> xpn = xp.next;
TreeNode<K, V> x = map.newTreeNode(h, k, v, xpn);
if(dir <= 0)
xp.left = x;
else
xp.right = x;
xp.next = x;
x.parent = x.prev = xp;
if(xpn != null)
((TreeNode<K, V>) xpn).prev = x;
moveRootToFront(tab, balanceInsertion(root, x));
return null;
}
}
}
/**
* Removes the given node, that must be present before this call.
* This is messier than typical red-black deletion code because we
* cannot swap the contents of an interior node with a leaf
* successor that is pinned by "next" pointers that are accessible
* independently during traversal. So instead we swap the tree
* linkages. If the current tree appears to have too few nodes,
* the bin is converted back to a plain bin. (The test triggers
* somewhere between 2 and 6 nodes, depending on tree structure).
*/
final void removeTreeNode(HashMap<K, V> map, Node<K, V>[] tab,
boolean movable){
int n;
if(tab == null || (n = tab.length) == 0)
return;
int index = (n - 1) & hash;
TreeNode<K, V> first = (TreeNode<K, V>) tab[index], root = first, rl;
TreeNode<K, V> succ = (TreeNode<K, V>) next, pred = prev;
if(pred == null)
tab[index] = first = succ;
else
pred.next = succ;
if(succ != null)
succ.prev = pred;
if(first == null)
return;
if(root.parent != null)
root = root.root();
if(root == null
|| (movable
&& (root.right == null
|| (rl = root.left) == null
|| rl.left == null))){
tab[index] = first.untreeify(map); // too small
return;
}
TreeNode<K, V> p = this, pl = left, pr = right, replacement;
if(pl != null && pr != null){
TreeNode<K, V> s = pr, sl;
while ((sl = s.left) != null) // find successor
s = sl;
boolean c = s.red;
s.red = p.red;
p.red = c; // swap colors
TreeNode<K, V> sr = s.right;
TreeNode<K, V> pp = p.parent;
if(s == pr){ // p was s's direct parent
p.parent = s;
s.right = p;
}else{
TreeNode<K, V> sp = s.parent;
if((p.parent = sp) != null){
if(s == sp.left)
sp.left = p;
else
sp.right = p;
}
if((s.right = pr) != null)
pr.parent = s;
}
p.left = null;
if((p.right = sr) != null)
sr.parent = p;
if((s.left = pl) != null)
pl.parent = s;
if((s.parent = pp) == null)
root = s;
else if(p == pp.left)
pp.left = s;
else
pp.right = s;
if(sr != null)
replacement = sr;
else
replacement = p;
}else if(pl != null)
replacement = pl;
else if(pr != null)
replacement = pr;
else
replacement = p;
if(replacement != p){
TreeNode<K, V> pp = replacement.parent = p.parent;
if(pp == null)
root = replacement;
else if(p == pp.left)
pp.left = replacement;
else
pp.right = replacement;
p.left = p.right = p.parent = null;
}
TreeNode<K, V> r = p.red ? root : balanceDeletion(root, replacement);
if(replacement == p){ // detach
TreeNode<K, V> pp = p.parent;
p.parent = null;
if(pp != null){
if(p == pp.left)
pp.left = null;
else if(p == pp.right)
pp.right = null;
}
}
if(movable)
moveRootToFront(tab, r);
}
/**
* Splits nodes in a tree bin into lower and upper tree bins,
* or untreeifies if now too small. Called only from resize;
* see above discussion about split bits and indices.
*
* @param map the map
* @param tab the table for recording bin heads
* @param index the index of the table being split
* @param bit the bit of hash to split on
*/
final void split(HashMap<K, V> map, Node<K, V>[] tab, int index, int bit){
TreeNode<K, V> b = this;
// Relink into lo and hi lists, preserving order
TreeNode<K, V> loHead = null, loTail = null;
TreeNode<K, V> hiHead = null, hiTail = null;
int lc = 0, hc = 0;
for(TreeNode<K, V> e = b, next; e != null; e = next){
next = (TreeNode<K, V>) e.next;
e.next = null;
if((e.hash & bit) == 0){
if((e.prev = loTail) == null)
loHead = e;
else
loTail.next = e;
loTail = e;
++lc;
}else{
if((e.prev = hiTail) == null)
hiHead = e;
else
hiTail.next = e;
hiTail = e;
++hc;
}
}
if(loHead != null){
if(lc <= UNTREEIFY_THRESHOLD)
tab[index] = loHead.untreeify(map);
else{
tab[index] = loHead;
if(hiHead != null) // (else is already treeified)
loHead.treeify(tab);
}
}
if(hiHead != null){
if(hc <= UNTREEIFY_THRESHOLD)
tab[index + bit] = hiHead.untreeify(map);
else{
tab[index + bit] = hiHead;
if(loHead != null)
hiHead.treeify(tab);
}
}
}
/* ------------------------------------------------------------ */
// Red-black tree methods, all adapted from CLR
//左旋
static <K, V> TreeNode<K, V> rotateLeft(TreeNode<K, V> root,
TreeNode<K, V> p){
TreeNode<K, V> r, pp, rl;
if(p != null && (r = p.right) != null){
if((rl = p.right = r.left) != null)
rl.parent = p;
if((pp = r.parent = p.parent) == null)
(root = r).red = false;
else if(pp.left == p)
pp.left = r;
else
pp.right = r;
r.left = p;
p.parent = r;
}
return root;
}
//右旋
static <K, V> TreeNode<K, V> rotateRight(TreeNode<K, V> root,
TreeNode<K, V> p){
TreeNode<K, V> l, pp, lr;
if(p != null && (l = p.left) != null){
if((lr = p.left = l.right) != null)
lr.parent = p;
if((pp = l.parent = p.parent) == null)
(root = l).red = false;
else if(pp.right == p)
pp.right = l;
else
pp.left = l;
l.right = p;
p.parent = l;
}
return root;
}
//平衡
static <K, V> TreeNode<K, V> balanceInsertion(TreeNode<K, V> root,
TreeNode<K, V> x){
x.red = true;
for(TreeNode<K, V> xp, xpp, xppl, xppr; ; ){
if((xp = x.parent) == null){
x.red = false;
return x;
}else if(!xp.red || (xpp = xp.parent) == null)
return root;
if(xp == (xppl = xpp.left)){
if((xppr = xpp.right) != null && xppr.red){
xppr.red = false;
xp.red = false;
xpp.red = true;
x = xpp;
}else{
if(x == xp.right){
root = rotateLeft(root, x = xp);
xpp = (xp = x.parent) == null ? null : xp.parent;
}
if(xp != null){
xp.red = false;
if(xpp != null){
xpp.red = true;
root = rotateRight(root, xpp);
}
}
}
}else{
if(xppl != null && xppl.red){
xppl.red = false;
xp.red = false;
xpp.red = true;
x = xpp;
}else{
if(x == xp.left){
root = rotateRight(root, x = xp);
xpp = (xp = x.parent) == null ? null : xp.parent;
}
if(xp != null){
xp.red = false;
if(xpp != null){
xpp.red = true;
root = rotateLeft(root, xpp);
}
}
}
}
}
}
//删除，平衡
static <K, V> TreeNode<K, V> balanceDeletion(TreeNode<K, V> root,
TreeNode<K, V> x){
for(TreeNode<K, V> xp, xpl, xpr; ; ){
if(x == null || x == root)
return root;
else if((xp = x.parent) == null){
x.red = false;
return x;
}else if(x.red){
x.red = false;
return root;
}else if((xpl = xp.left) == x){
if((xpr = xp.right) != null && xpr.red){
xpr.red = false;
xp.red = true;
root = rotateLeft(root, xp);
xpr = (xp = x.parent) == null ? null : xp.right;
}
if(xpr == null)
x = xp;
else{
TreeNode<K, V> sl = xpr.left, sr = xpr.right;
if((sr == null || !sr.red) &&
(sl == null || !sl.red)){
xpr.red = true;
x = xp;
}else{
if(sr == null || !sr.red){
if(sl != null)
sl.red = false;
xpr.red = true;
root = rotateRight(root, xpr);
xpr = (xp = x.parent) == null ?
null : xp.right;
}
if(xpr != null){
xpr.red = (xp == null) ? false : xp.red;
if((sr = xpr.right) != null)
sr.red = false;
}
if(xp != null){
xp.red = false;
root = rotateLeft(root, xp);
}
x = root;
}
}
}else{ // symmetric
if(xpl != null && xpl.red){
xpl.red = false;
xp.red = true;
root = rotateRight(root, xp);
xpl = (xp = x.parent) == null ? null : xp.left;
}
if(xpl == null)
x = xp;
else{
TreeNode<K, V> sl = xpl.left, sr = xpl.right;
if((sl == null || !sl.red) &&
(sr == null || !sr.red)){
xpl.red = true;
x = xp;
}else{
if(sl == null || !sl.red){
if(sr != null)
sr.red = false;
xpl.red = true;
root = rotateLeft(root, xpl);
xpl = (xp = x.parent) == null ?
null : xp.left;
}
if(xpl != null){
xpl.red = (xp == null) ? false : xp.red;
if((sl = xpl.left) != null)
sl.red = false;
}
if(xp != null){
xp.red = false;
root = rotateRight(root, xp);
}
x = root;
}
}
}
}
}
/**
* Recursive invariant check
*/
static <K, V> boolean checkInvariants(TreeNode<K, V> t){
TreeNode<K, V> tp = t.parent, tl = t.left, tr = t.right,
tb = t.prev, tn = (TreeNode<K, V>) t.next;
if(tb != null && tb.next != t)
return false;
if(tn != null && tn.prev != t)
return false;
if(tp != null && t != tp.left && t != tp.right)
return false;
if(tl != null && (tl.parent != t || tl.hash > t.hash))
return false;
if(tr != null && (tr.parent != t || tr.hash < t.hash))
return false;
if(t.red && tl != null && tl.red && tr != null && tr.red)
return false;
if(tl != null && !checkInvariants(tl))
return false;
if(tr != null && !checkInvariants(tr))
return false;
return true;
}
}
}
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