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package com.kaka.util;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.NoSuchElementException;
import java.util.Random;
import static com.kaka.util.MathUtils.nextPowerOfTwo;
/**
* int为键的map
*
* @param 泛型参数
* @author zkpursuit
*/
public class IntMap implements Serializable {
// primes for hash functions 2, 3, and 4
private static final int PRIME2 = 0xbe1f14b1;
private static final int PRIME3 = 0xb4b82e39;
private static final int PRIME4 = 0xced1c241;
private static final int EMPTY = 0;
static Random random = new Random();
private int size;
int[] keyTable;
V[] valueTable;
int capacity, stashSize;
V zeroValue;
boolean hasZeroValue;
private float loadFactor;
private int hashShift, mask, threshold;
private int stashCapacity;
private int pushIterations;
private boolean isBigTable;
/**
* Creates a new map with an initial capacity of 32 and a load factor of
* 0.8. This map will hold 25 items before growing the backing table.
*/
public IntMap() {
this(32, 0.8f);
}
/**
* Creates a new map with a load factor of 0.8. This map will hold
* initialCapacity * 0.8 items before growing the backing table.
*/
public IntMap(int initialCapacity) {
this(initialCapacity, 0.8f);
}
/**
* Creates a new map with the specified initial capacity and load factor.
* This map will hold initialCapacity * loadFactor items before growing the
* backing table.
*/
public IntMap(int initialCapacity, float loadFactor) {
if (initialCapacity < 0) {
throw new IllegalArgumentException("initialCapacity must be >= 0: " + initialCapacity);
}
if (initialCapacity > 1 << 30) {
throw new IllegalArgumentException("initialCapacity is too large: " + initialCapacity);
}
capacity = nextPowerOfTwo(initialCapacity);
if (loadFactor <= 0) {
throw new IllegalArgumentException("loadFactor must be > 0: " + loadFactor);
}
this.loadFactor = loadFactor;
// big table is when capacity >= 2^16
isBigTable = (capacity >>> 16) != 0 ? true : false;
threshold = (int) (capacity * loadFactor);
mask = capacity - 1;
hashShift = 31 - Integer.numberOfTrailingZeros(capacity);
stashCapacity = Math.max(3, (int) Math.ceil(Math.log(capacity)) * 2);
pushIterations = Math.max(Math.min(capacity, 8), (int) Math.sqrt(capacity) / 8);
keyTable = new int[capacity + stashCapacity];
valueTable = (V[]) new Object[keyTable.length];
}
/**
* Creates a new map identical to the specified map.
*/
public IntMap(IntMap map) {
this(map.capacity, map.loadFactor);
stashSize = map.stashSize;
System.arraycopy(map.keyTable, 0, keyTable, 0, map.keyTable.length);
System.arraycopy(map.valueTable, 0, valueTable, 0, map.valueTable.length);
size = map.size;
zeroValue = map.zeroValue;
hasZeroValue = map.hasZeroValue;
}
public V put(int key, V value) {
if (key == 0) {
V oldValue = zeroValue;
zeroValue = value;
if (!hasZeroValue) {
hasZeroValue = true;
size++;
}
return oldValue;
}
// avoid getfield opcode
int[] keyTable = this.keyTable;
int mask = this.mask;
boolean isBigTable = this.isBigTable;
// Check for existing keys.
int index1 = key & mask;
int key1 = keyTable[index1];
if (key1 == key) {
V oldValue = valueTable[index1];
valueTable[index1] = value;
return oldValue;
}
int index2 = hash2(key);
int key2 = keyTable[index2];
if (key2 == key) {
V oldValue = valueTable[index2];
valueTable[index2] = value;
return oldValue;
}
int index3 = hash3(key);
int key3 = keyTable[index3];
if (key3 == key) {
V oldValue = valueTable[index3];
valueTable[index3] = value;
return oldValue;
}
int index4 = -1;
int key4 = -1;
if (isBigTable) {
index4 = hash4(key);
key4 = keyTable[index4];
if (key4 == key) {
V oldValue = valueTable[index4];
valueTable[index4] = value;
return oldValue;
}
}
// Update key in the stash.
for (int i = capacity, n = i + stashSize; i < n; i++) {
if (keyTable[i] == key) {
V oldValue = valueTable[i];
valueTable[i] = value;
return oldValue;
}
}
// Check for empty buckets.
if (key1 == EMPTY) {
keyTable[index1] = key;
valueTable[index1] = value;
if (size++ >= threshold) {
resize(capacity << 1);
}
return null;
}
if (key2 == EMPTY) {
keyTable[index2] = key;
valueTable[index2] = value;
if (size++ >= threshold) {
resize(capacity << 1);
}
return null;
}
if (key3 == EMPTY) {
keyTable[index3] = key;
valueTable[index3] = value;
if (size++ >= threshold) {
resize(capacity << 1);
}
return null;
}
if (isBigTable && key4 == EMPTY) {
keyTable[index4] = key;
valueTable[index4] = value;
if (size++ >= threshold) {
resize(capacity << 1);
}
return null;
}
push(key, value, index1, key1, index2, key2, index3, key3, index4, key4);
;
return null;
}
public void putAll(IntMap map) {
for (Entry entry : map.entries()) {
put(entry.key, entry.value);
}
}
/**
* Skips checks for existing keys.
*/
private void putResize(int key, V value) {
if (key == 0) {
zeroValue = value;
hasZeroValue = true;
return;
}
// Check for empty buckets.
int index1 = key & mask;
int key1 = keyTable[index1];
if (key1 == EMPTY) {
keyTable[index1] = key;
valueTable[index1] = value;
if (size++ >= threshold) {
resize(capacity << 1);
}
return;
}
int index2 = hash2(key);
int key2 = keyTable[index2];
if (key2 == EMPTY) {
keyTable[index2] = key;
valueTable[index2] = value;
if (size++ >= threshold) {
resize(capacity << 1);
}
return;
}
int index3 = hash3(key);
int key3 = keyTable[index3];
if (key3 == EMPTY) {
keyTable[index3] = key;
valueTable[index3] = value;
if (size++ >= threshold) {
resize(capacity << 1);
}
return;
}
int index4 = -1;
int key4 = -1;
if (isBigTable) {
index4 = hash4(key);
key4 = keyTable[index4];
if (key4 == EMPTY) {
keyTable[index4] = key;
valueTable[index4] = value;
if (size++ >= threshold) {
resize(capacity << 1);
}
return;
}
}
push(key, value, index1, key1, index2, key2, index3, key3, index4, key4);
}
private void push(int insertKey, V insertValue, int index1, int key1, int index2, int key2, int index3, int key3, int index4,
int key4) {
// avoid getfield opcode
int[] keyTable = this.keyTable;
V[] valueTable = this.valueTable;
int mask = this.mask;
boolean isBigTable = this.isBigTable;
// Push keys until an empty bucket is found.
int evictedKey;
V evictedValue;
int i = 0, pushIterations = this.pushIterations;
int n = isBigTable ? 4 : 3;
do {
// Replace the key and value for one of the hashes.
switch (random.nextInt(n)) {
case 0:
evictedKey = key1;
evictedValue = valueTable[index1];
keyTable[index1] = insertKey;
valueTable[index1] = insertValue;
break;
case 1:
evictedKey = key2;
evictedValue = valueTable[index2];
keyTable[index2] = insertKey;
valueTable[index2] = insertValue;
break;
case 2:
evictedKey = key3;
evictedValue = valueTable[index3];
keyTable[index3] = insertKey;
valueTable[index3] = insertValue;
break;
default:
evictedKey = key4;
evictedValue = valueTable[index4];
keyTable[index4] = insertKey;
valueTable[index4] = insertValue;
break;
}
// If the evicted key hashes to an empty bucket, put it there and stop.
index1 = evictedKey & mask;
key1 = keyTable[index1];
if (key1 == EMPTY) {
keyTable[index1] = evictedKey;
valueTable[index1] = evictedValue;
if (size++ >= threshold) {
resize(capacity << 1);
}
return;
}
index2 = hash2(evictedKey);
key2 = keyTable[index2];
if (key2 == EMPTY) {
keyTable[index2] = evictedKey;
valueTable[index2] = evictedValue;
if (size++ >= threshold) {
resize(capacity << 1);
}
return;
}
index3 = hash3(evictedKey);
key3 = keyTable[index3];
if (key3 == EMPTY) {
keyTable[index3] = evictedKey;
valueTable[index3] = evictedValue;
if (size++ >= threshold) {
resize(capacity << 1);
}
return;
}
if (isBigTable) {
index4 = hash4(evictedKey);
key4 = keyTable[index4];
if (key4 == EMPTY) {
keyTable[index4] = evictedKey;
valueTable[index4] = evictedValue;
if (size++ >= threshold) {
resize(capacity << 1);
}
return;
}
}
if (++i == pushIterations) {
break;
}
insertKey = evictedKey;
insertValue = evictedValue;
} while (true);
putStash(evictedKey, evictedValue);
}
private void putStash(int key, V value) {
if (stashSize == stashCapacity) {
// Too many pushes occurred and the stash is full, increase the table size.
resize(capacity << 1);
put(key, value);
return;
}
// Store key in the stash.
int index = capacity + stashSize;
keyTable[index] = key;
valueTable[index] = value;
stashSize++;
size++;
}
public V get(int key) {
if (key == 0) {
if (!hasZeroValue) {
return null;
}
return zeroValue;
}
int index = key & mask;
if (keyTable[index] != key) {
index = hash2(key);
if (keyTable[index] != key) {
index = hash3(key);
if (keyTable[index] != key) {
if (isBigTable) {
index = hash4(key);
if (keyTable[index] != key) {
return getStash(key, null);
}
} else {
return getStash(key, null);
}
}
}
}
return valueTable[index];
}
public V get(int key, V defaultValue) {
if (key == 0) {
if (!hasZeroValue) {
return defaultValue;
}
return zeroValue;
}
int index = key & mask;
if (keyTable[index] != key) {
index = hash2(key);
if (keyTable[index] != key) {
index = hash3(key);
if (keyTable[index] != key) {
if (isBigTable) {
index = hash4(key);
if (keyTable[index] != key) {
return getStash(key, defaultValue);
}
} else {
return getStash(key, defaultValue);
}
}
}
}
return valueTable[index];
}
private V getStash(int key, V defaultValue) {
int[] keyTable = this.keyTable;
for (int i = capacity, n = i + stashSize; i < n; i++) {
if (keyTable[i] == key) {
return valueTable[i];
}
}
return defaultValue;
}
public V remove(int key) {
if (key == 0) {
if (!hasZeroValue) {
return null;
}
V oldValue = zeroValue;
zeroValue = null;
hasZeroValue = false;
size--;
return oldValue;
}
int index = key & mask;
if (keyTable[index] == key) {
keyTable[index] = EMPTY;
V oldValue = valueTable[index];
valueTable[index] = null;
size--;
return oldValue;
}
index = hash2(key);
if (keyTable[index] == key) {
keyTable[index] = EMPTY;
V oldValue = valueTable[index];
valueTable[index] = null;
size--;
return oldValue;
}
index = hash3(key);
if (keyTable[index] == key) {
keyTable[index] = EMPTY;
V oldValue = valueTable[index];
valueTable[index] = null;
size--;
return oldValue;
}
if (isBigTable) {
index = hash4(key);
if (keyTable[index] == key) {
keyTable[index] = EMPTY;
V oldValue = valueTable[index];
valueTable[index] = null;
size--;
return oldValue;
}
}
return removeStash(key);
}
V removeStash(int key) {
int[] keyTable = this.keyTable;
for (int i = capacity, n = i + stashSize; i < n; i++) {
if (keyTable[i] == key) {
V oldValue = valueTable[i];
removeStashIndex(i);
size--;
return oldValue;
}
}
return null;
}
void removeStashIndex(int index) {
// If the removed location was not last, move the last tuple to the removed location.
stashSize--;
int lastIndex = capacity + stashSize;
if (index < lastIndex) {
keyTable[index] = keyTable[lastIndex];
valueTable[index] = valueTable[lastIndex];
valueTable[lastIndex] = null;
} else {
valueTable[index] = null;
}
}
/**
* Reduces the size of the backing arrays to be the specified capacity or
* less. If the capacity is already less, nothing is done. If the map
* contains more items than the specified capacity, the next highest power
* of two capacity is used instead.
*/
public void shrink(int maximumCapacity) {
if (maximumCapacity < 0) {
throw new IllegalArgumentException("maximumCapacity must be >= 0: " + maximumCapacity);
}
if (size > maximumCapacity) {
maximumCapacity = size;
}
if (capacity <= maximumCapacity) {
return;
}
maximumCapacity = nextPowerOfTwo(maximumCapacity);
resize(maximumCapacity);
}
public int size() {
return size;
}
/**
* Clears the map and reduces the size of the backing arrays to be the
* specified capacity if they are larger.
*/
public void clear(int maximumCapacity) {
if (capacity <= maximumCapacity) {
clear();
return;
}
zeroValue = null;
hasZeroValue = false;
size = 0;
resize(maximumCapacity);
}
public void clear() {
int[] keyTable = this.keyTable;
V[] valueTable = this.valueTable;
for (int i = capacity + stashSize; i-- > 0; ) {
keyTable[i] = EMPTY;
valueTable[i] = null;
}
size = 0;
stashSize = 0;
zeroValue = null;
hasZeroValue = false;
}
/**
* Returns true if the specified value is in the map. Note this traverses
* the entire map and compares every value, which may be an expensive
* operation.
*
* @param identity If true, uses == to compare the specified value with
* values in the map. If false, uses {@link #equals(Object)}.
*/
public boolean containsValue(Object value, boolean identity) {
V[] valueTable = this.valueTable;
if (value == null) {
if (hasZeroValue && zeroValue == null) {
return true;
}
int[] keyTable = this.keyTable;
for (int i = capacity + stashSize; i-- > 0; ) {
if (keyTable[i] != EMPTY && valueTable[i] == null) {
return true;
}
}
} else if (identity) {
if (value == zeroValue) {
return true;
}
for (int i = capacity + stashSize; i-- > 0; ) {
if (valueTable[i] == value) {
return true;
}
}
} else {
if (hasZeroValue && value.equals(zeroValue)) {
return true;
}
for (int i = capacity + stashSize; i-- > 0; ) {
if (value.equals(valueTable[i])) {
return true;
}
}
}
return false;
}
public boolean containsKey(int key) {
if (key == 0) {
return hasZeroValue;
}
int index = key & mask;
if (keyTable[index] != key) {
index = hash2(key);
if (keyTable[index] != key) {
index = hash3(key);
if (keyTable[index] != key) {
if (isBigTable) {
index = hash4(key);
if (keyTable[index] != key) {
return containsKeyStash(key);
}
} else {
return containsKeyStash(key);
}
}
}
}
return true;
}
private boolean containsKeyStash(int key) {
int[] keyTable = this.keyTable;
for (int i = capacity, n = i + stashSize; i < n; i++) {
if (keyTable[i] == key) {
return true;
}
}
return false;
}
/**
* Returns the key for the specified value, or notFound if it is
* not in the map. Note this traverses the entire map and compares every
* value, which may be an expensive operation.
*
* @param identity If true, uses == to compare the specified value with
* values in the map. If false, uses {@link #equals(Object)}.
*/
public int findKey(Object value, boolean identity, int notFound) {
V[] valueTable = this.valueTable;
if (value == null) {
if (hasZeroValue && zeroValue == null) {
return 0;
}
int[] keyTable = this.keyTable;
for (int i = capacity + stashSize; i-- > 0; ) {
if (keyTable[i] != EMPTY && valueTable[i] == null) {
return keyTable[i];
}
}
} else if (identity) {
if (value == zeroValue) {
return 0;
}
for (int i = capacity + stashSize; i-- > 0; ) {
if (valueTable[i] == value) {
return keyTable[i];
}
}
} else {
if (hasZeroValue && value.equals(zeroValue)) {
return 0;
}
for (int i = capacity + stashSize; i-- > 0; ) {
if (value.equals(valueTable[i])) {
return keyTable[i];
}
}
}
return notFound;
}
/**
* Increases the size of the backing array to acommodate the specified
* number of additional items. Useful before adding many items to avoid
* multiple backing array resizes.
*/
public void ensureCapacity(int additionalCapacity) {
int sizeNeeded = size + additionalCapacity;
if (sizeNeeded >= threshold) {
resize(nextPowerOfTwo((int) (sizeNeeded / loadFactor)));
}
}
private void resize(int newSize) {
int oldEndIndex = capacity + stashSize;
capacity = newSize;
threshold = (int) (newSize * loadFactor);
mask = newSize - 1;
hashShift = 31 - Integer.numberOfTrailingZeros(newSize);
stashCapacity = Math.max(3, (int) Math.ceil(Math.log(newSize)) * 2);
pushIterations = Math.max(Math.min(newSize, 8), (int) Math.sqrt(newSize) / 8);
// big table is when capacity >= 2^16
isBigTable = (capacity >>> 16) != 0 ? true : false;
int[] oldKeyTable = keyTable;
V[] oldValueTable = valueTable;
keyTable = new int[newSize + stashCapacity];
valueTable = (V[]) new Object[newSize + stashCapacity];
int oldSize = size;
size = hasZeroValue ? 1 : 0;
stashSize = 0;
if (oldSize > 0) {
for (int i = 0; i < oldEndIndex; i++) {
int key = oldKeyTable[i];
if (key != EMPTY) {
putResize(key, oldValueTable[i]);
}
}
}
}
private int hash2(int h) {
h *= PRIME2;
return (h ^ h >>> hashShift) & mask;
}
private int hash3(int h) {
h *= PRIME3;
return (h ^ h >>> hashShift) & mask;
}
private int hash4(int h) {
h *= PRIME4;
return (h ^ h >>> hashShift) & mask;
}
public String toString() {
if (size == 0) {
return "[]";
}
StringBuilder buffer = new StringBuilder(32);
buffer.append('[');
int[] keyTable = this.keyTable;
V[] valueTable = this.valueTable;
int i = keyTable.length;
if (hasZeroValue) {
buffer.append("0=");
buffer.append(zeroValue);
} else {
while (i-- > 0) {
int key = keyTable[i];
if (key == EMPTY) {
continue;
}
buffer.append(key);
buffer.append('=');
buffer.append(valueTable[i]);
break;
}
}
while (i-- > 0) {
int key = keyTable[i];
if (key == EMPTY) {
continue;
}
buffer.append(", ");
buffer.append(key);
buffer.append('=');
buffer.append(valueTable[i]);
}
buffer.append(']');
return buffer.toString();
}
/**
* Returns an iterator for the entries in the map. Remove is supported. Note
* that the same iterator instance is returned each time this method is
* called. Use the {@link Entries} constructor for nested or multithreaded
* iteration.
*/
public Entries entries() {
return new Entries(this);
}
/**
* Returns an iterator for the values in the map. Remove is supported. Note
* that the same iterator instance is returned each time this method is
* called. Use the {@link Entries} constructor for nested or multithreaded
* iteration.
*/
public Values values() {
return new Values(this);
}
/**
* Returns an iterator for the keys in the map. Remove is supported. Note
* that the same iterator instance is returned each time this method is
* called. Use the {@link Entries} constructor for nested or multithreaded
* iteration.
*/
public Keys keys() {
return new Keys(this);
}
static public class Entry {
public int key;
public V value;
public String toString() {
return key + "=" + value;
}
}
static private class MapIterator {
static final int INDEX_ILLEGAL = -2;
static final int INDEX_ZERO = -1;
public boolean hasNext;
final IntMap map;
int nextIndex, currentIndex;
public MapIterator(IntMap map) {
this.map = map;
reset();
}
public void reset() {
currentIndex = INDEX_ILLEGAL;
nextIndex = INDEX_ZERO;
if (map.hasZeroValue) {
hasNext = true;
} else {
findNextIndex();
}
}
void findNextIndex() {
hasNext = false;
int[] keyTable = map.keyTable;
for (int n = map.capacity + map.stashSize; ++nextIndex < n; ) {
if (keyTable[nextIndex] != EMPTY) {
hasNext = true;
break;
}
}
}
public void remove() {
if (currentIndex == INDEX_ZERO && map.hasZeroValue) {
map.zeroValue = null;
map.hasZeroValue = false;
} else if (currentIndex < 0) {
throw new IllegalStateException("next must be called before remove.");
} else if (currentIndex >= map.capacity) {
map.removeStashIndex(currentIndex);
nextIndex = currentIndex - 1;
findNextIndex();
} else {
map.keyTable[currentIndex] = EMPTY;
map.valueTable[currentIndex] = null;
}
currentIndex = INDEX_ILLEGAL;
map.size--;
}
}
static public class Entries extends MapIterator implements Iterable>, Iterator> {
private Entry entry = new Entry();
public Entries(IntMap map) {
super(map);
}
/**
* Note the same entry instance is returned each time this method is
* called.
*/
public Entry next() {
if (!hasNext) {
throw new NoSuchElementException();
}
int[] keyTable = map.keyTable;
if (nextIndex == INDEX_ZERO) {
entry.key = 0;
entry.value = map.zeroValue;
} else {
entry.key = keyTable[nextIndex];
entry.value = map.valueTable[nextIndex];
}
currentIndex = nextIndex;
findNextIndex();
return entry;
}
public boolean hasNext() {
return hasNext;
}
public Iterator> iterator() {
return this;
}
}
static public class Values extends MapIterator implements Iterable, Iterator {
public Values(IntMap map) {
super(map);
}
public boolean hasNext() {
return hasNext;
}
public V next() {
if (!hasNext) {
throw new NoSuchElementException();
}
V value;
if (nextIndex == INDEX_ZERO) {
value = map.zeroValue;
} else {
value = map.valueTable[nextIndex];
}
currentIndex = nextIndex;
findNextIndex();
return value;
}
public Iterator iterator() {
return this;
}
/**
* Returns a new array containing the remaining values.
*/
public ArrayList toArray() {
ArrayList array = new ArrayList<>(map.size);
while (hasNext) {
array.add(next());
}
return array;
}
}
static public class Keys extends MapIterator {
public Keys(IntMap map) {
super(map);
}
public int next() {
if (!hasNext) {
throw new NoSuchElementException();
}
int key = nextIndex == INDEX_ZERO ? 0 : map.keyTable[nextIndex];
currentIndex = nextIndex;
findNextIndex();
return key;
}
/**
* Returns a new array containing the remaining keys.
*/
public IntArray toArray() {
IntArray array = new IntArray(true, map.size);
while (hasNext) {
array.add(next());
}
return array;
}
}
}