package map;
public class HashMap1<K,V> extends AbstractMap1<K,V> implements Map1<K,V>, Cloneable, Serializable {
private static final long serialVersionUID = 362498820763181265L;
static final int DEFAULT_INITIAL_CAPACITY = 1 << 4;//不直接写16，因为快，16也要转换为0 1，
static final int MAXIMUM_CAPACITY = 1 << 30;//最大容量，要是2的幂次方
//数组长度超过0.75就扩容。默认初始容量是16，加载因子是0.75。容量是哈希表中桶(Entry数组)的数量，
//当哈希表中的条目数超出了加载因子与当前容量的乘积时，通过调用 rehash 方法将容量翻倍。
static final float DEFAULT_LOAD_FACTOR = 0.75f;
//一个链表超过8个就变为红黑树
static final int TREEIFY_THRESHOLD = 8;
//数组
public transient Node<K,V>[] table;//长度必须为2的幂
//大小，链表元素个数。
transient int size;
transient int modCount;//用于快速失败。遍历时候不能修改。
int threshold;//capacity * load factor, 下次扩容的临界值，size>=threshold就会扩容
final float loadFactor;//负载因子可以改
static final int UNTREEIFY_THRESHOLD = 6;
static final int MIN_TREEIFY_CAPACITY = 64;//数组长度小于64先扩容，先不转为红黑树，
public static final int hash(Object key) {
int h;//hashCode是native的，返回int。将hashCode的高16位参与运算
return (key == null) ? 0 : (h = key.hashCode()) ^ (h >>> 16);//>>>左边补0
}
//如果x实现了Comparable接口，则返回 x的Class。
public static Class<?> comparableClassFor(Object x) {
if (x instanceof Comparable) {//实现了Comparable接口
Class<?> c; Type[] ts, as; Type t; ParameterizedType p;
if ((c = x.getClass()) == String.class) //String就返回String
return c;
if ((ts = c.getGenericInterfaces()) != null) {//所有的接口，只要有一个接口是Comparable
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;
}
//Returns k.compareTo(x) if x matches kc
public static int compareComparables(Class<?> kc, Object k, Object x) {
return (x == null || x.getClass() != kc ? 0 : ((Comparable)k).compareTo(x));
}
public static final int tableSizeFor(int cap) {
//128:128,127:128,129:256,255:256,257:512。
//负数：32位，最高位是1，最后32位全是1，就返回-1。
//正数：最高位开始全是1：2^n - 1 + 1,就是最近大的2的幂次方
int n = cap- 1;//如果cap就是2的幂次方，就不要找最近的大了，就是自己。
System.out.println(Integer.toBinaryString(n));
n |= n >>> 1;
System.out.println(Integer.toBinaryString(n));
n |= n >>> 2;
System.out.println(Integer.toBinaryString(n));
n |= n >>> 4;
System.out.println(Integer.toBinaryString(n));
n |= n >>> 8;
System.out.println(Integer.toBinaryString(n));
n |= n >>> 16;
System.out.println(Integer.toBinaryString(n));//32位全部变成1，
System.out.println(n);
return (n < 0) ? 1 : (n >= MAXIMUM_CAPACITY) ? MAXIMUM_CAPACITY : n + 1;
}
transient Set<Map1.Entry<K,V>> entrySet;
//负载因子小，数组就大，内存占用大，由于数组多那么就会导致链表短，数组查找O(1)链表短那么查找就快，负载因子小数组就小，链表就长，内存小，由于链表长了，查找时间慢。
//加载因子这里是可以大于1的。
public HashMap1(int initialCapacity, float loadFactor) {//负载因子可以改
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);//临界值，最近大的2的幂次方。此时容量是0。
}
public HashMap1(int initialCapacity) {
this(initialCapacity, DEFAULT_LOAD_FACTOR);
}
public HashMap1() {
this.loadFactor = DEFAULT_LOAD_FACTOR; // all other fields defaulted
}
public HashMap1(Map1<? extends K, ? extends V> m) {
this.loadFactor = DEFAULT_LOAD_FACTOR;
putMapEntries(m, false);
}
public final void putMapEntries(Map1<? extends K, ? extends V> m, boolean evict) {//通过entrySet来put
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 (Map1.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;
}
public final Node<K,V> getNode(int hash, Object key) {
Node<K, V>[] tab;Node<K, V> first/* 链表第一个元素 */, e/* 下一个节点 */;int n/* 长度 */; K k;
if ((tab = table) != null && (n = tab.length) > 0 && (first = tab[(n - 1) & hash]) != null) {
if (first.hash == hash && ((k = first.key) == key || (key != null && key.equals(k))))
return first;//就是第一个元素
if ((e = first.next) != null) {
if (first instanceof TreeNode)
return ((TreeNode<K,V>)first).getTreeNode(hash, key);
do {//查找链表
if (e.hash == hash && ((k = e.key) == key || (key != null && key.equals(k))))
return e;
} while ((e = e.next) != null);
}
}
return null;
}
public boolean containsKey(Object key) {
return getNode(hash(key), key) != null;
}
public V put(K key, V value) {//已经存在就替换
return putVal(hash(key), key, value, false, true);
}
public final V putVal(int hash, K key, V value, boolean onlyIfAbsent,boolean evict) {//onlyIfAbsent=true已经存在就不修改旧值。
Node<K,V>[] tab;//数组table
Node<K,V> p/*tab[i]的元素*/;
int n/*数组长度*/, i/*所在数组的索引*/;
if ((tab = table) == null || (n = tab.length) == 0)//为空就去初始化。
n = (tab = resize()).length;//&运算比取模效率高很多，
if ((p = tab[i = (n - 1) & hash]) == null)//(table.length - 1) & hash(key)是要放的位置，对table.length取余。数组长度要是2的幂次方。
tab[i] = newNode(hash, key, value, null);//为null直接放
else {//数组上也就是链表头有元素，
Node<K,V> e/*找到的元素*/; K k;
if (p.hash == hash && ((k = p.key) == key || (key != null && key.equals(k))))
e = p; //就是链表的头结点替换
else if (p instanceof TreeNode)//红黑树节点是TreeNode，链表节点是Node
e = ((TreeNode<K,V>)p).putTreeVal(this, tab, hash, key, value);
else {//不是头结点，向下找，
for (int binCount = 0; ; ++binCount) {
if ((e = p.next) == null) {//链表末尾
//节点的hash就是key的hash。
p.next = newNode(hash, key, value, null);//放在链表末尾，链表添加节点。
if (binCount >= TREEIFY_THRESHOLD - 1) //7，== null：已经走到了末尾，就计算一直到末尾有多少个元素。已经有8个添加第9个元素时候treeifyBin()
treeifyBin(tab, hash);//转成红黑树
break;
}
System.out.println(e.hash);//走到这里e!=null,
if (e.hash == hash && ((k = e.key) == key || (key != null && key.equals(k))))//e!=null，看是不是e，找到链表中这个节点e，
break;
p = e;//查找e下一个
}
}
if (e != null) { //e不等于null，找到的就是e,替换e。
V oldValue = e.value;
if (!onlyIfAbsent || oldValue == null)//onlyIfAbsent=false就修改。
e.value = value;
afterNodeAccess(e);
return oldValue;
}
}
++modCount;
if (++size > threshold)//链表节点总数大于阈值就扩容，不是数组非空个数大于阈值。
resize();//扩容
afterNodeInsertion(evict);
return null;
}
public final Node<K,V>[] resize() {//初始化和扩容2倍，2个作用，
Node<K,V>[] oldTab = table;//原来table作为旧的table,
int oldCap = (oldTab == null) ? 0 : oldTab.length;//旧容量
int oldThr = threshold;//旧临界值
int newCap, newThr = 0;//新容量，新临界值
if (oldCap > 0) {//旧容量大于0
if (oldCap >= MAXIMUM_CAPACITY) {//旧容量大于1073741824
threshold = Integer.MAX_VALUE;//旧临界值=2147483647
return oldTab;//返回旧table
} //旧容量乘以2小于最大值，就扩容2倍。临界值也变成2倍。
else if ((newCap = oldCap << 1) < MAXIMUM_CAPACITY && oldCap >= DEFAULT_INITIAL_CAPACITY)
newThr = oldThr << 1; //临界值也变成2倍。
}
else if (oldThr > 0) // 旧容量小于0，旧临界值大于0，
newCap = oldThr;//新容量=旧临界值
else { // 旧容量小于0，旧临界值小于0，
newCap = DEFAULT_INITIAL_CAPACITY;//新容量=16
newThr = (int)(DEFAULT_LOAD_FACTOR * DEFAULT_INITIAL_CAPACITY);//12,size(链表个数)大于12就扩容，不是数组个数大于12.
}
if (newThr == 0) {//新临界值=0，
float ft = (float)newCap * loadFactor;
newThr = (newCap < MAXIMUM_CAPACITY && ft < (float)MAXIMUM_CAPACITY ? (int)ft : Integer.MAX_VALUE);
}
threshold = newThr;
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/*每个链表的头元素*/;
if ((e = oldTab[j]) != null) {
oldTab[j] = null;
if (e.next == null)//链表就一个元素，直接放，不就覆盖了？所有元素重新计算索引，不会覆盖。
//每列元素都是在自己位置或者加8（数组长度从16变成32）的位置，一个链表的元素不会抢占另一个链表元素的位置。
newTab[e.hash & (newCap - 1)] = e;
else if (e instanceof TreeNode)//红黑树
((TreeNode<K,V>)e).split(this, newTab, j, oldCap);
else {//链表，不是红黑树
//遍历一个链表时候，这个链表上的所有元素重新计算位置时候，要么在原来索引位置，要么在加8（数组长度从16变成32）的位置。
//所以就有2哥链表。
Node<K,V> loHead = null, loTail = null; //不动的元素，还在原来位置
Node<K,V> hiHead = null, hiTail = null; //加上8的位置的元素
Node<K,V> next;
do {//遍历数组某一列的所有元素
next = e.next;
if ((e.hash & oldCap) == 0) {//不动的元素，还在原来位置
//0,1,2,3,4,5,6,7,8*2,8*4,8*8,8*16.......的组合。原始容量是8扩容后是16。对8和16取余不变，所以索引位置不变。
if (loTail == null)
loHead = e;//0=00,32=32,64=64,96=96,128=128,16扩容变成32后，32的倍数不变，
else
loTail.next = e;
loTail = e;
}
else {//8 + 0,1,2,3,4,5,6,7,8*2,8*4,8*8,8*16.......的组合。取余加上8即可。
if (hiTail == null)
hiHead = e;//48=48,80=80,112=112,144=144,16扩容变成32后，16奇数被的放到+16位置，
else
hiTail.next = e;
hiTail = e;
}
} while ((e = next) != null);
if (loTail != null) {
loTail.next = null;
newTab[j] = loHead;//直接放到新数组上面去，不就覆盖了？所有元素重新计算索引，不会覆盖。
}
if (hiTail != null) {
hiTail.next = null;
newTab[j + oldCap] = hiHead;
}
}
}
}
}
return newTab;
}
public final void treeifyBin(Node<K,V>[] tab, int hash) {//hash位置的链表转为红黑树
int n = tab.length, index;
Node<K,V> e;
/*if (tab == null || n < MIN_TREEIFY_CAPACITY)//数组长度小于64先扩容，先不转为红黑树，
resize();//注释掉，转为红黑树测试。
else*/ if ((e = tab[index = (n - 1) & hash]) != null) {//e有9个元素,e是第一个。
TreeNode<K,V> hd = null, tl = null;
do {
TreeNode<K,V> p = replacementTreeNode(e, null);//new TreeNode<>(p.hash, p.key, p.value, null);
//TreeNode有parent，left，right，prev，before, after，hash，key，value，next;
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);//从头开始，把这个链表变成红黑树。hd可能不再是tab[index]，因为红黑树顶点会变成一个新的，不一定是hd。
}
}
public void putAll(Map1<? extends K, ? extends V> m) {
putMapEntries(m, true);
}
public V remove(Object key) {
Node<K,V> e;
return (e = removeNode(hash(key), key, null, false, true)) == null ? null : e.value;
}
public final Node<K,V> removeNode(int hash, Object key, Object value,boolean matchValue, boolean movable) {
Node<K,V>[] tab;
Node<K,V> p/*数组的链表头元素*/;
int n/*数组长度*/, index/*查找的索引*/;
if ((tab = table) != null && (n = tab.length) > 0 &&(p = tab[index = (n - 1) & hash]) != null) {
Node<K,V> node = null/*找到的元素*/, e/*链表下一个元素*/;
K k; V v;
if (p.hash == hash && ((k = p.key) == key || (key != null && key.equals(k))))
node = p;//找到的就是头元素
else if ((e = p.next) != null) {//头元素下一个元素
if (p instanceof TreeNode)//头结点是红黑树
node = ((TreeNode<K,V>)p).getTreeNode(hash, key);//红黑树查找，从头结点开始查找，
else {//头结点不是红黑树
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)))) {//matchValue=false就根据key删除不根据value
if (node instanceof TreeNode)//头结点是红黑树
((TreeNode<K,V>)node).removeTreeNode(this, tab, movable);//红黑树删除
else if (node == p)//第一个元素直接替换
tab[index] = node.next;
else
p.next = node.next;//改变指针
++modCount;
--size;
afterNodeRemoval(node);
return node;
}
}
return null;
}
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;//数组每个第一个元素置位null。
}
}
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) {//先遍历数组
for (Node<K,V> e = tab[i]; e != null; e = e.next) {//再遍历链表
if ((v = e.value) == value || (value != null && value.equals(v)))
return true;
}
}
}
return false;
}
@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/*第一个元素*/;
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;//扩容或者初始化
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; //找到的元素
K k;
do {
if (e.hash == hash && ((k = e.key) == key || (key != null && key.equals(k)))) {
old = e;//找到元素
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;//扩容或者初始化
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);//链表也遍历
}
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);//链表也遍历
}
}
if (modCount != mc)
throw new ConcurrentModificationException();
}
}
@Override
public Object clone() {
HashMap1<K,V> result;
try {
result = (HashMap1<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);
}
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);//一个个的写出去
s.writeObject(e.value);
}
}
}
}
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, Map1.Entry[].class, cap);
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++) {
K key = (K) s.readObject();
V value = (V) s.readObject();
putVal(hash(key), key, value, false, false);
}
}
}
Node<K,V> newNode(int hash, K key, V value, Node<K,V> next) {
return new Node<>(hash, key, value, next);
}
Node<K,V> replacementNode(Node<K,V> p, Node<K,V> next) {
return new Node<>(p.hash, p.key, p.value, next);
}
TreeNode<K,V> newTreeNode(int hash, K key, V value, Node<K,V> next) {
return new TreeNode<>(hash, key, value, next);
}
TreeNode<K,V> replacementTreeNode(Node<K,V> p, Node<K,V> next) {
return new TreeNode<>(p.hash, p.key, p.value, next);
}
//重新初始化，Called by clone and readObject.
void reinitialize() {
table = null;
entrySet = null;
keySet = null;
values = null;
modCount = 0;
threshold = 0;
size = 0;
}
// LinkedHashMap使用：后置动作，LinkedHashMap extends HashMap
void afterNodeAccess(Node<K,V> p) { }
void afterNodeInsertion(boolean evict) { }
void afterNodeRemoval(Node<K,V> p) { }
/* ---------Map里面需要输出集合，并且遍历集合，还有分割。--------------------------------------------------- */
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() { HashMap1.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<>(HashMap1.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();
}
}
}
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() { HashMap1.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<>(HashMap1.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) {//直接使用外部类的属性table
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();
}
}
}
public Set<Map1.Entry<K,V>> entrySet() {
Set<Map1.Entry<K,V>> es;
es = entrySet == null ? (entrySet = new EntrySet()) : entrySet;
System.out.println(es);
return es;
}
final class EntrySet extends AbstractSet<Map1.Entry<K,V>> {
public final int size() { return size; }
public final void clear() { HashMap1.this.clear(); }
public final Iterator<Map1.Entry<K,V>> iterator() {
return new EntryIterator();
}
public final boolean contains(Object o) {
if (!(o instanceof Map1.Entry))
return false;
Map1.Entry<?,?> e = (Map1.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 Map1.Entry) {
Map1.Entry<?,?> e = (Map1.Entry<?,?>) o;
Object key = e.getKey();
Object value = e.getValue();
return removeNode(hash(key), key, value, true, true) != null;
}
return false;
}
public final Spliterator<Map1.Entry<K,V>> spliterator() {
return new EntrySpliterator<>(HashMap1.this, 0, -1, 0, 0);
}
public final void forEach(Consumer<? super Map1.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();
}
}
}
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;//current是刚刚出去的节点，next是还没有出去的节点。
index = 0;//遍历时候，所在数组索引。
if (t != null && size > 0) {
do {//初始化时候，next=数组中第一个不为null的元素，也是这个链表的头元素。
} 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)//遍历时候不能修改
throw new ConcurrentModificationException();
if (e == null)
throw new NoSuchElementException();
if ((next = (current = e).next) == null && (t = table) != null) {//链表末尾了
do {} while (index < t.length && (next = t[index++]) == null);//找下一个数组元素，也就是新的链表头元素。
}
return e;
}
public final void remove() {//移出去current
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);//modCount++,就不能遍历了？下面修改expectedModCount为新的modCount。
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<Map1.Entry<K,V>> {
public final Map1.Entry<K,V> next() { return nextNode(); }
}
static class HashMapSpliterator<K,V> {
final HashMap1<K,V> map;
Node<K,V> current;
int index; //开始位置
int fence; //结束位置
int est; //大小
int expectedModCount;
HashMapSpliterator(HashMap1<K,V> m, int origin, int fence, int est, int expectedModCount) {
this.map = m;
this.index = origin;//开始位置
this.fence = fence;//结束位置
this.est = est;//大小
this.expectedModCount = expectedModCount;
}
final int getFence() {
int hi;
if ((hi = fence) < 0) {
HashMap1<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(HashMap1<K,V> m, int origin, int fence, int est, int expectedModCount) {
super(m, origin, fence, est, expectedModCount);//new KeySpliterator<>(HashMap1.this, 0, -1, 0, 0);
}
public KeySpliterator<K,V> trySplit() {//把数组切割分出去
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();
HashMap1<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);//数组链表都要遍历
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) {//数组链表都要遍历
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(HashMap1<K,V> m, int origin, int fence, int est, int expectedModCount) {
super(m, origin, fence, est, expectedModCount);//new ValueSpliterator<>(HashMap1.this, 0, -1, 0, 0);
}
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();
HashMap1<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<Map1.Entry<K,V>> {
EntrySpliterator(HashMap1<K,V> m, int origin, int fence, int est, int expectedModCount) {
super(m, origin, fence, est, expectedModCount);//new EntrySpliterator<>(HashMap1.this, 0, -1, 0, 0);
}
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 Map1.Entry<K,V>> action) {
int i, hi, mc;
if (action == null)
throw new NullPointerException();
HashMap1<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 Map1.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;
}
}
/* ---------Map里面需要输出集合，并且遍历集合。--------------------------------------------------- */
// HashMap1.TreeNode extends LinkedHashMap1.Entry extends HashMap1.Node implements Map.Entry，
static final class TreeNode<K,V> extends LinkedHashMap1.Entry<K,V> {//红黑树
TreeNode<K,V> parent; // red-black tree links，上级节点
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);
}
// public final TreeNode<K,V> getParent() { return parent; }
// public final TreeNode<K,V> getLeft() { return left; }
// public final TreeNode<K,V> getRight() { return right; }
// public final TreeNode<K,V> getPrev() { return prev; }
public String toString() {
return "key:"+key+",val:"+value+(red==true?"，红":"，黑");
// +(next!=null?",next:("+next.toString()+")":"") //不能造成递归toString()
// +(prev!=null?",prev:"+prev.key:"")
// +(parent!=null?",parent:"+parent.key:"")
// +(left!=null?",left:("+left.toString()+")":"")
// +(right!=null?",right:("+right.toString()+")":"");
}
//包含这个节点的树的根节点
final TreeNode<K,V> root() {
for (TreeNode<K,V> r = this, p;;) {
if ((p = r.parent) == null)//一直找父节点，就会找到根，
return r;
r = p;
}
}
//红黑树根节点是数组的链表的第一个元素。红黑树和链表特性同时存在。
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;//root节点所在数组的索引
TreeNode<K,V> first = (TreeNode<K,V>)tab[index];
if (root != first) {//根节点变换了
Node<K,V> rn;
tab[index] = root;//红黑树的根设置给数组元素
TreeNode<K,V> rp = root.prev;
if ((rn = root.next) != null)
((TreeNode<K,V>)rn).prev = rp;
if (rp != null)
rp.next = rn;//把root从链表的prev和next中移除，
if (first != null)
first.prev = root;
root.next = first;
root.prev = null;
}
boolean b = checkInvariants(root);
assert b;
}
}
final TreeNode<K,V> find(int h, Object k, Class<?> kc) {//查找节点
TreeNode<K,V> p = this;// this为调用此方法的节点
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 ||
// comparableClassFor是如果key实现了Comparable就返回具体类型，否则返回null
// compareComparables是比较传入的key和当前遍历元素的key
// 只有当前hash值与传入的hash值一致才会走到这里
//如果传入的key(k)所属的类实现了Comparable接口,则将传入的key跟p节点的key比较
(kc = comparableClassFor(k)) != null) && // 此行不为空代表k实现了Comparable
(dir = compareComparables(kc, k, pk)) != 0)//k<pk则dir<0, k>pk则dir>0
p = (dir < 0) ? pl : pr;// k < pk则向左遍历(p赋值为p的左节点), 否则向右遍历
//代码走到此处, 代表key所属类没有实现Comparable, 直接指定向p的右边遍历
else if ((q = pr.find(h, k, kc)) != null)
return q;
else// 代码走到此处代表上一个向右遍历（pr.find(h, k, kc)）为空, 因此直接向左遍历
p = pl;
} while (p != null);
return null;
}
// 查找节点
final TreeNode<K,V> getTreeNode(int h, Object k) {
return ((parent != null) ? root() : this).find(h, k, null);
}
// 用于不可比较或者hashCode相同时进行比较的方法
static int tieBreakOrder(Object a, Object b) {
int d;//a b类的名字相等
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;
}
//返回根节点
final void treeify(Node<K,V>[] tab) {
TreeNode<K,V> root = null;
for (TreeNode<K,V> x = this, next; x != null; x = next) {//遍历放每一个节点
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;;) {//一个节点找位置
int dir, ph;
K pk = p.key;
if ((ph = p.hash) > h)//根节点 > x
dir = -1;//左边
else if (ph < h)//根节点 < x
dir = 1;//右边
//相等
else if ((kc == null && (kc = comparableClassFor(k)) == null) || (dir = compareComparables(kc, k, pk)) == 0)
dir = tieBreakOrder(k, pk);//Hash(k) <= Hash(pk) ? -1 : 1，小于根节点在根的左边，大于根节点在根的右边。
TreeNode<K,V> xp = p;
if ((p = (dir <= 0) ? p.left : p.right) == null) {//放到左边就看p.left,放到右边就看p.right。不为null就放，为null就继续指向左或者右节点。
x.parent = xp;
if (dir <= 0)
xp.left = x;
else
xp.right = x;
root = balanceInsertion(root, x);//重新调整平衡树，返回新的root。
break;//跳出
}
}
}
}//红黑树构造完在moveRootToFront()。红黑树根节点是数组的第一个元素
moveRootToFront(tab, root);//root节点可能不是原来第一个节点，
}
//红黑树太少了变成链表
final Node<K,V> untreeify(HashMap1<K,V> map) {
Node<K,V> hd = null, tl = null;//头尾节点
for (Node<K,V> q = this; q != null; q = q.next) {//this是first节点。红黑树里面的next属性，就是为了以后少了的时候变成红黑树用的。
Node<K,V> p = map.replacementNode(q, null);//创建new Node()节点，
if (tl == null)
hd = p;
else
tl.next = p;
tl = p;
}
return hd;
}
//红黑是添加节点，不是链表添加节点
final TreeNode<K,V> putTreeVal(HashMap1<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;;) {//找到红黑树根节点
int dir, ph; K pk;
if ((ph = p.hash) > h)//h在p左边
dir = -1;
else if (ph < h)//h在p右边
dir = 1;
else if ((pk = p.key) == k || (k != null && k.equals(pk)))//h=p
return p;
// comparableClassFor是如果key实现了Comparable就返回具体类型，否则返回null
// compareComparables是比较传入的key和当前遍历元素的key
// 只有当前hash值与传入的hash值一致才会走到这里
// 如果k所属的类没有实现Comparable接口 或者 k和p节点的key相等
else if ((kc == null && (kc = comparableClassFor(k)) == null) || (dir = compareComparables(kc, k, pk)) == 0) {
if (!searched) {//第一次符合条件, 该方法只有第一次才执行
TreeNode<K,V> q, ch;
searched = true;
// 从p节点的左节点和右节点分别调用find方法进行查找, 如果查找到目标节点则返回
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;
}// 否则使用定义的一套规则来比较k和p节点的key的大小, 用来决定向左还是向右查找
dir = tieBreakOrder(k, pk);// dir<0则代表k<pk，则向p左边查找；反之亦然
}
TreeNode<K,V> xp = p;//要放的时候的根节点
if ((p = (dir <= 0) ? p.left : p.right) == null) {//等于null就放
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));//红黑树根节点是数组链表的第一个元素
return null;
}
}
}
//节点自己调用，删除自己，传进来整个map，整个table。一个链表维护了链表的前驱后继关系（便于后面删除，变少了，再次转换为链表时用），也维护了红黑树的关系。
final void removeTreeNode(HashMap1<K,V> map, Node<K,V>[] tab, boolean movable) {
int n;
if (tab == null || (n = tab.length) == 0)
return;
int index = (n - 1) & hash;//hash是这个要删除节点的hash，96
TreeNode<K,V> first = (TreeNode<K,V>)tab[index], root = first, rl;//first是数组中链表的第一个，root是红黑树的根，
TreeNode<K,V> succ = (TreeNode<K,V>)next, pred = prev;//96节点自己的prev，next。
if (pred == null)//根节点在第一个，没有prev，删除的是根节点。考虑空，只有一个元素，2个元素，3个元素。
tab[index] = first = succ;//链表头指向next，成为链表的第一个，
else
pred.next = succ;//链表关系重建
if (succ != null)//最后一个节点
succ.prev = pred;
if (first == null)// tab[index]=null或者就一个元素
return;
if (root.parent != null)
root = root.root();//找根节点
if (root == null || root.right == null || (rl = root.left) == null || rl.left == null) {
tab[index] = first.untreeify(map); // 红黑树转成链表，第一个节点来调用。已经删除节点了。
return;
}
TreeNode<K,V> p = this, pl = left, pr = right, replacement;//this=p是要删除的节点，left，right是左右节点
if (pl != null && pr != null) {//有左右节点。交换p和后继元素。
TreeNode<K, V> s/* 后驱 */ = pr/* p的右节点 */, sl/* 查找后驱时候用 */;
while ((sl = s.left) != null) // 找删除节点p的后驱s
s = sl;//一个节点只有左或者右节点，删除之后不会影响平衡性，如果有左右节点删除后会影响平衡性，所以先用后驱替代，后驱只有一个子节点，删除后驱不会影响平衡性。
boolean c = s.red; s.red = p.red; p.red = c; // p和后驱s交换颜色。
//交换p和p的后驱。
TreeNode<K, V> sr = s.right;/* 后驱右节点 */
TreeNode<K, V> pp = p.parent;/* 删除节点父节点 */
if (s == pr) { // p的后驱s是p的右节点，p的右节点没有左节点
p.parent = s;
s.right = p;//先改变p和s的关系
}
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;//p的left没有节点
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;
//交换p和p的后驱s完毕，指正交换完毕，
if (sr != null)//后驱只有右节点，没有左节点，所以用后驱的右节点替代后驱，就是删除后驱。
replacement = sr;
else
replacement = p;//此时p在p的后驱的位置
}
else if (pl != null)//没有右节点，只有左节点
replacement = pl;//左节点放到删除位置
else if (pr != null)//只有右节点，没有左节点
replacement = pr;//右节点放到删除位置
else//左右节点都没有
replacement = p;
if (replacement != p) {//代替节点！=p，删除p节点，replacement移到p的位置，
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;
}
//删除是黑节点，黑高变了，从replacement调整红黑树。
TreeNode<K,V> r = p.red ? root : balanceDeletion(root, replacement);
if (replacement == p) { // 删除p
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);//把根节点移到链表的开头
}
//红黑树扩容时候调用((TreeNode<K,V>)e).split(this, newTab, j, oldCap);
final void split(HashMap1<K,V> map, Node<K,V>[] tab, int index, int bit) {
TreeNode<K,V> b = this;
// 2个链表
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) {//扩容之后还在原来位置的
if ((e.prev = loTail) == null)
loHead = e;
else
loTail.next = e;
loTail = e;
++lc;
}
else {//扩容之后在原来位置 + oldCap的
if ((e.prev = hiTail) == null)
hiHead = e;
else
hiTail.next = e;
hiTail = e;
++hc;
}
}
if (loHead != null) {
if (lc <= UNTREEIFY_THRESHOLD)//小于6转成链表
tab[index] = loHead.untreeify(map);//红黑树节点太少了变成链表
else {//大于6转成红黑树
tab[index] = loHead;
if (hiHead != null) // hiHead==null，说明就一个链表，红黑树没有拆散，直接用这个红黑树就可以。
loHead.treeify(tab);//loHead链表转成红黑树
}
}
if (hiHead != null) {
if (hc <= UNTREEIFY_THRESHOLD)//小于6转成链表
tab[index + bit] = hiHead.untreeify(map);
else {//大于6转成红黑树
tab[index + bit] = hiHead;
if (loHead != null)//loHead = null，说明就一个链表，红黑树没有拆散，直接用这个红黑树就可以。
hiHead.treeify(tab);//hiHead链表转成红黑树
}
}
}
// 左旋转p
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;//新的顶点变成新的根节点才修改root为新的顶点p.right，否则root不变还是原来的根。
else if (pp.left == p)
pp.left = r;
else
pp.right = r;
r.left = p;
p.parent = r;
}
return root;
}
// 右旋转p
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;//新的顶点变成新的根节点才修改root为新的顶点p.left，否则root不变还是原来的根。
else if (pp.right == p)
pp.right = l;
else
pp.left = l;
l.right = p;
p.parent = l;
}
return root;
}
//返回新的root
static <K,V> TreeNode<K,V> balanceInsertion(TreeNode<K,V> root, TreeNode<K,V> x) {
x.red = true;//插入的是红节点
for (TreeNode<K, V> xp/* 父 */, xpp/* 爷爷 */, xppl/* 爷爷左 */, xppr/* 爷爷右 */;;) {
if ((xp = x.parent) == null) {//没有父节点。 插入0
x.red = false;//变黑，返回
return x;//就是根节点
}
else if (!xp.red || (xpp = xp.parent) == null)//父节点黑色，没有爷爷节点
return root;//返回新的顶点。 插入32
if (xp == (xppl = xpp.left)) {//爷爷左边
if ((xppr = xpp.right) != null && xppr.red) {//爷爷右节点红色
xppr.red = false;
xp.red = false;
xpp.red = true;
x = xpp;//父亲变黑，爷爷右节点变黑，爷爷变红，x指向爷爷继续判断。修改X。root不变，继续判断x。
}
else {//爷爷右节点黑色
if (x == xp.right) {//父亲右边
root = rotateLeft(root, x = xp);//左旋父亲 ，返回新的顶点，不是返回根节点。没有break。修改X,XP,XPP。
xpp = (xp = x.parent) == null ? null : xp.parent;//root可能变成新的顶点，继续判断父亲。
}
if (xp != null) {//父亲左边
//父亲变黑，爷爷变红，右旋转爷爷
xp.red = false;
if (xpp != null) {
xpp.red = true;
root = rotateRight(root, xpp);//返回根节点。root可能变成新的顶点，继续判断x。
}
}
}
}
else {//爷爷右边
if (xppl != null && xppl.red) {//爷爷左边红色
xppl.red = false;
xp.red = false;
xpp.red = true;
x = xpp;//父亲变黑，爷爷左边变黑，爷爷变红，x指向爷爷继续判断。root不变，继续判断爷爷。 插入64 96 128
}
else {//爷爷左边黑色
if (x == xp.left) {//父亲左边
root = rotateRight(root, x = xp);//右旋转父亲。修改X,XP,XPP。root可能变成新的顶点，继续判断父亲。
xpp = (xp = x.parent) == null ? null : xp.parent;
}
if (xp != null) {//父亲右边
xp.red = false;
if (xpp != null) {
xpp.red = true;
root = rotateLeft(root, xpp);//父亲变黑，爷爷变红，左旋转爷爷。可能root变成新的顶点，继续判断x。插入48 80 112
}
}
}
}
}
}
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;
}
}
}
}
}
//从根开始检查整个树红黑特性，以及prev和next特性。
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)//前面节点的下一个节点 不等于 这个节点
return false;
if (tn != null && tn.prev != t)//后面节点的前一个节点不等于这个节点
return false;
if (tp != null && t != tp.left && t != tp.right)//parent.left!=这个节点，并且parent.right!=这个节点
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)//不能2层红
return false;
if (tl != null && !checkInvariants(tl))
return false;
if (tr != null && !checkInvariants(tr))
return false;
return true;
}
}
// HashMap1.TreeNode extends LinkedHashMap1.Entry extends HashMap1.Node implements Map.Entry，
static class Node<K,V> implements Map1.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 Node<K,V> getNext() { return next; }
public String toString() { return key + "=" + value +","+ ((next != null) ? next.toString() : ""); }
public final int hashCode() {//native方法
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 Map1.Entry) {
Map1.Entry<?,?> e = (Map1.Entry<?,?>)o;
if (Objects.equals(key, e.getKey()) && Objects.equals(value, e.getValue()))
return true;
}
return false;
}
}
}