/*
* DBeaver - Universal Database Manager
* Copyright (C) 2010-2017 Serge Rider (serge@jkiss.org)
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.jkiss.utils;
import java.util.*;
/**
Map with int key.
*/
@SuppressWarnings("unchecked")
public class IntKeyMap<VALUE> implements Map<Integer, VALUE> {
/**
* The default initial capacity - MUST be a power of two.
*/
static final int DEFAULT_INITIAL_CAPACITY = 16;
/**
* The maximum capacity, used if a higher value is implicitly specified
* by either of the constructors with arguments.
* MUST be a power of two <= 1<<30.
*/
static final int MAXIMUM_CAPACITY = 1 << 30;
/**
* The load fast used when none specified in constructor.
**/
static final float DEFAULT_LOAD_FACTOR = 0.75f;
/**
* The table, resized as necessary. Length MUST Always be a power of two.
*/
transient IntEntry<VALUE>[] table;
/**
* The number of key-value mappings contained in this identity hash map.
*/
transient int size;
/**
* The next size value at which to resize (capacity * load factor).
* @serial
*/
int threshold;
/**
* The load factor for the hash table.
*
* @serial
*/
final float loadFactor;
/**
* The number of times this IntKeyMap has been structurally modified
*/
transient volatile int modCount;
/**
* Constructs an empty <tt>IntKeyMap</tt> with the specified initial
* capacity and load factor.
*
* @param initialCapacity The initial capacity.
* @param loadFactor The load factor.
* @throws IllegalArgumentException if the initial capacity is negative
* or the load factor is nonpositive.
*/
public IntKeyMap(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);
// Find a power of 2 >= initialCapacity
int capacity = 1;
while (capacity < initialCapacity)
capacity <<= 1;
this.loadFactor = loadFactor;
threshold = (int)(capacity * loadFactor);
table = new IntEntry[capacity];
}
/**
* Constructs an empty <tt>IntKeyMap</tt> with the specified initial
* capacity and the default load factor (0.75).
*
* @param initialCapacity the initial capacity.
* @throws IllegalArgumentException if the initial capacity is negative.
*/
public IntKeyMap(int initialCapacity) {
this(initialCapacity, DEFAULT_LOAD_FACTOR);
}
/**
* Constructs an empty <tt>IntKeyMap</tt> with the default initial capacity
* (16) and the default load factor (0.75).
*/
public IntKeyMap() {
this.loadFactor = DEFAULT_LOAD_FACTOR;
threshold = DEFAULT_INITIAL_CAPACITY;
table = new IntEntry[DEFAULT_INITIAL_CAPACITY];
}
static int hash(long x) {
int h = (int)(x ^ (x >>> 32));
h += ~(h << 9);
h ^= (h >>> 14);
h += (h << 4);
h ^= (h >>> 10);
return h;
}
/**
* Returns index for hash code h.
*/
static int indexFor(int h, int length) {
return h & (length-1);
}
/**
* Returns the number of key-value mappings in this map.
*
* @return the number of key-value mappings in this map.
*/
@Override
public int size() {
return size;
}
/**
* Returns <tt>true</tt> if this map contains no key-value mappings.
*
* @return <tt>true</tt> if this map contains no key-value mappings.
*/
@Override
public boolean isEmpty()
{
return size == 0;
}
@Override
public boolean containsKey(Object key)
{
return containsKey(((Number)key).intValue());
}
/**
* Returns the value to which the specified key is mapped in this identity
* hash map, or <tt>null</tt> if the map contains no mapping for this key.
* A return value of <tt>null</tt> does not <i>necessarily</i> indicate
* that the map contains no mapping for the key; it is also possible that
* the map explicitly maps the key to <tt>null</tt>. The
* <tt>containsKey</tt> method may be used to distinguish these two cases.
*
* @param key the key whose associated value is to be returned.
* @return the value to which this map maps the specified key, or
* <tt>null</tt> if the map contains no mapping for this key.
* @see #put(int, Object)
*/
public VALUE get(int key) {
int hash = hash(key);
int i = indexFor(hash, table.length);
IntEntry<VALUE> e = table[i];
while (true) {
if (e == null)
return null;
if (e.hash == hash && key == e.key)
return e.value;
e = e.next;
}
}
/**
* Returns <tt>true</tt> if this map contains a mapping for the
* specified key.
*/
public boolean containsKey(int key)
{
int hash = hash(key);
int i = indexFor(hash, table.length);
IntEntry<VALUE> e = table[i];
while (e != null) {
if (e.hash == hash && key == e.key)
return true;
e = e.next;
}
return false;
}
/**
* Returns the entry associated with the specified key in the
* IntKeyMap. Returns null if the IntKeyMap contains no mapping
* for this key.
*/
IntEntry<VALUE> getEntry(int key) {
int hash = hash(key);
int i = indexFor(hash, table.length);
IntEntry<VALUE> e = table[i];
while (e != null && !(e.hash == hash && key == e.key))
e = e.next;
return e;
}
/**
* Associates the specified value with the specified key in this map.
* If the map previously contained a mapping for this key, the old
* value is replaced.
*
* @param key key with which the specified value is to be associated.
* @param value value to be associated with the specified key.
* @return previous value associated with specified key, or <tt>null</tt>
* if there was no mapping for key. A <tt>null</tt> return can
* also indicate that the IntKeyMap previously associated
* <tt>null</tt> with the specified key.
*/
public VALUE put(int key, VALUE value) {
int hash = hash(key);
int i = indexFor(hash, table.length);
for (IntEntry<VALUE> e = table[i]; e != null; e = e.next) {
if (e.hash == hash && key == e.key) {
VALUE oldValue = e.value;
e.value = value;
return oldValue;
}
}
modCount++;
addEntry(hash, key, value, i);
return null;
}
/**
* This method is used instead of put by constructors and
* pseudoconstructors (clone, readObject). It does not resize the table,
* check for comodification, etc. It calls createEntry rather than
* addEntry.
*/
private void putForCreate(int key, VALUE value) {
int hash = hash(key);
int i = indexFor(hash, table.length);
/**
* Look for preexisting entry for key. This will never happen for
* clone or deserialize. It will only happen for construction if the
* input Map is a sorted map whose ordering is inconsistent w/ equals.
*/
for (IntEntry<VALUE> e = table[i]; e != null; e = e.next) {
if (e.hash == hash && key == e.key) {
e.value = value;
return;
}
}
createEntry(hash, key, value, i);
}
void putAllForCreate(IntKeyMap<VALUE> m) {
for (Iterator i = m.entrySet().iterator(); i.hasNext(); ) {
IntEntry<VALUE> e = (IntEntry<VALUE>) i.next();
putForCreate(e.key, e.value);
}
}
/**
* Rehashes the contents of this map into a new <tt>IntKeyMap</tt> instance
* with a larger capacity. This method is called automatically when the
* number of keys in this map exceeds its capacity and load factor.
*
* @param newCapacity the new capacity, MUST be a power of two.
*/
void resize(int newCapacity) {
// assert (newCapacity & -newCapacity) == newCapacity; // power of 2
IntEntry[] oldTable = table;
int oldCapacity = oldTable.length;
// check if needed
if (size < threshold || oldCapacity > newCapacity)
return;
IntEntry<VALUE>[] newTable = new IntEntry[newCapacity];
transfer(newTable);
table = newTable;
threshold = (int)(newCapacity * loadFactor);
}
/**
* Transfer all entries from current table to newTable.
*/
void transfer(IntEntry[] newTable) {
IntEntry<VALUE>[] src = table;
int newCapacity = newTable.length;
for (int j = 0; j < src.length; j++) {
IntEntry<VALUE> e = src[j];
if (e != null) {
src[j] = null;
do {
IntEntry<VALUE> next = e.next;
int i = indexFor(e.hash, newCapacity);
e.next = newTable[i];
newTable[i] = e;
e = next;
} while (e != null);
}
}
}
/**
* Copies all of the mappings from the specified map to this map
* These mappings will replace any mappings that
* this map had for any of the keys currently in the specified map.
*
* @param t mappings to be stored in this map.
* @throws NullPointerException if the specified map is null.
*/
public void putAll(IntKeyMap<VALUE> t) {
// Expand enough to hold t's elements without resizing.
int n = t.size();
if (n == 0)
return;
if (n >= threshold) {
n = (int)(n / loadFactor + 1);
if (n > MAXIMUM_CAPACITY)
n = MAXIMUM_CAPACITY;
int capacity = table.length;
while (capacity < n)
capacity <<= 1;
resize(capacity);
}
for (Iterator i = t.entrySet().iterator(); i.hasNext(); ) {
IntEntry<VALUE> e = (IntEntry<VALUE>) i.next();
put(e.key, e.value);
}
}
/**
* Removes the mapping for this key from this map if present.
*
* @param key key whose mapping is to be removed from the map.
* @return previous value associated with specified key, or <tt>null</tt>
* if there was no mapping for key. A <tt>null</tt> return can
* also indicate that the map previously associated <tt>null</tt>
* with the specified key.
*/
public VALUE remove(int key) {
IntEntry<VALUE> e = removeEntryForKey(key);
return (e == null ? null : e.value);
}
/**
* Removes and returns the entry associated with the specified key
* in the IntKeyMap. Returns null if the IntKeyMap contains no mapping
* for this key.
*/
IntEntry<VALUE> removeEntryForKey(int key) {
int hash = hash(key);
int i = indexFor(hash, table.length);
IntEntry<VALUE> prev = table[i];
IntEntry<VALUE> e = prev;
while (e != null) {
IntEntry<VALUE> next = e.next;
if (e.hash == hash && key == e.key) {
modCount++;
size--;
if (prev == e)
table[i] = next;
else
prev.next = next;
return e;
}
prev = e;
e = next;
}
return e;
}
/**
* Special version of remove for EntrySet.
*/
IntEntry<VALUE> removeMapping(Object o) {
if (!(o instanceof IntEntry))
return null;
IntEntry<VALUE> entry = (IntEntry<VALUE>)o;
int hash = hash(entry.key);
int i = indexFor(hash, table.length);
IntEntry<VALUE> prev = table[i];
IntEntry<VALUE> e = prev;
while (e != null) {
IntEntry<VALUE> next = e.next;
if (e.hash == hash && e.equals(entry)) {
modCount++;
size--;
if (prev == e)
table[i] = next;
else
prev.next = next;
return e;
}
prev = e;
e = next;
}
return e;
}
/**
* Removes all mappings from this map.
*/
@Override
public void clear() {
modCount++;
IntEntry<VALUE> tab[] = table;
for (int i = 0; i < tab.length; i++)
tab[i] = null;
size = 0;
}
/**
* Returns <tt>true</tt> if this map maps one or more keys to the
* specified value.
*
* @param value value whose presence in this map is to be tested.
* @return <tt>true</tt> if this map maps one or more keys to the
* specified value.
*/
@Override
public boolean containsValue(Object value)
{
if (value == null)
return containsNullValue();
IntEntry<VALUE> tab[] = table;
for (int i = 0; i < tab.length ; i++)
for (IntEntry<VALUE> e = tab[i] ; e != null ; e = e.next)
if (value.equals(e.value))
return true;
return false;
}
@Override
public VALUE get(Object key)
{
return get(((Number)key).intValue());
}
@Override
public VALUE put(Integer key, VALUE value)
{
return put(key.intValue(), value);
}
@Override
public VALUE remove(Object key)
{
return remove(((Number)key).intValue());
}
@Override
public void putAll(Map<? extends Integer, ? extends VALUE> t)
{
throw new UnsupportedOperationException();
}
/**
* Special-case code for containsValue with null argument
**/
private boolean containsNullValue()
{
IntEntry<VALUE> tab[] = table;
for (int i = 0; i < tab.length ; i++)
for (IntEntry<VALUE> e = tab[i] ; e != null ; e = e.next)
if (e.value == null)
return true;
return false;
}
public static class IntEntry<VALUE> implements Entry<Integer, VALUE> {
final int key;
VALUE value;
final int hash;
IntEntry<VALUE> next;
/**
* Create new entry.
*/
IntEntry(int h, int k, VALUE v, IntEntry<VALUE> n) {
value = v;
next = n;
key = k;
hash = h;
}
public int getInt() {
return key;
}
@Override
public Integer getKey()
{
return key;
}
@Override
public VALUE getValue() {
return value;
}
@Override
public VALUE setValue(VALUE newValue) {
VALUE oldValue = value;
value = newValue;
return oldValue;
}
public boolean equals(Object o) {
if (!(o instanceof IntEntry))
return false;
IntEntry<VALUE> e = (IntEntry<VALUE>)o;
if (key == e.key) {
VALUE v1 = getValue();
VALUE v2 = e.getValue();
if (v1 == v2 || (v1 != null && v1.equals(v2)))
return true;
}
return false;
}
public int hashCode() {
return hash(key) ^ (value==null ? 0 : value.hashCode());
}
public String toString() {
return String.valueOf(key) + "=" + getValue();
}
}
/**
* Add a new entry with the specified key, value and hash code to
* the specified bucket. It is the responsibility of this
* method to resize the table if appropriate.
*
* Subclass overrides this to alter the behavior of put method.
*/
void addEntry(int hash, int key, VALUE value, int bucketIndex) {
table[bucketIndex] = new IntEntry<>(hash, key, value, table[bucketIndex]);
if (size++ >= threshold)
resize(2 * table.length);
}
/**
* Like addEntry except that this version is used when creating entries
* as part of Map construction or "pseudo-construction" (cloning,
* deserialization). This version needn't worry about resizing the table.
*
* Subclass overrides this to alter the behavior of IntKeyMap(Map),
* clone, and readObject.
*/
void createEntry(int hash, int key, VALUE value, int bucketIndex) {
table[bucketIndex] = new IntEntry<>(hash, key, value, table[bucketIndex]);
size++;
}
private abstract class HashIterator<T> implements Iterator<T> {
IntEntry<VALUE> next; // next entry to return
int expectedModCount; // For fast-fail
int index; // current slot
IntEntry<VALUE> current; // current entry
HashIterator() {
expectedModCount = modCount;
IntEntry<VALUE>[] t = table;
int i = t.length;
IntEntry<VALUE> n = null;
if (size != 0) { // advance to first entry
while (i > 0 && (n = t[--i]) == null)
;
}
next = n;
index = i;
}
@Override
public boolean hasNext() {
return next != null;
}
IntEntry<VALUE> nextEntry() {
if (modCount != expectedModCount)
throw new ConcurrentModificationException();
IntEntry<VALUE> e = next;
if (e == null)
throw new NoSuchElementException();
IntEntry<VALUE> n = e.next;
IntEntry<VALUE>[] t = table;
int i = index;
while (n == null && i > 0)
n = t[--i];
index = i;
next = n;
return current = e;
}
@Override
public void remove() {
if (current == null)
throw new IllegalStateException();
if (modCount != expectedModCount)
throw new ConcurrentModificationException();
int k = current.key;
current = null;
IntKeyMap.this.removeEntryForKey(k);
expectedModCount = modCount;
}
}
private class ValueIterator extends HashIterator<VALUE> {
@Override
public VALUE next() {
return nextEntry().value;
}
}
private class KeyIterator extends HashIterator<Integer> {
@Override
public Integer next() {
return nextEntry().key;
}
public int nextInt() {
return nextEntry().key;
}
}
private class EntryIterator extends HashIterator<IntEntry<VALUE>> {
@Override
public IntEntry<VALUE> next() {
return nextEntry();
}
}
// Subclass overrides these to alter behavior of views' iterator() method
Iterator<Integer> newKeyIterator()
{
return new KeyIterator();
}
Iterator<VALUE> newValueIterator()
{
return new ValueIterator();
}
Iterator<IntEntry<VALUE>> newEntryIterator()
{
return new EntryIterator();
}
// Views
private transient Set<IntEntry<VALUE>> entrySet = null;
transient volatile Set<Integer> keySet = null;
transient volatile Collection<VALUE> values = null;
/**
* Returns a set view of the keys contained in this map. The set is
* backed by the map, so changes to the map are reflected in the set, and
* vice-versa. The set supports element removal, which removes the
* corresponding mapping from this map, via the <tt>Iterator.remove</tt>,
* <tt>Set.remove</tt>, <tt>removeAll</tt>, <tt>retainAll</tt>, and
* <tt>clear</tt> operations. It does not support the <tt>add</tt> or
* <tt>addAll</tt> operations.
*
* @return a set view of the keys contained in this map.
*/
@Override
public Set<Integer> keySet() {
Set<Integer> ks = keySet;
return (ks != null ? ks : (keySet = new KeySet()));
}
private class KeySet extends AbstractSet<Integer> {
@Override
public Iterator<Integer> iterator() {
return newKeyIterator();
}
@Override
public int size() {
return size;
}
@Override
public boolean contains(Object o) {
if (o instanceof Number) {
return containsKey(((Number)o).intValue());
} else {
return false;
}
}
@Override
public boolean remove(Object o) {
if (o instanceof Number) {
return IntKeyMap.this.removeEntryForKey(((Number)o).intValue()) != null;
} else {
return false;
}
}
@Override
public void clear() {
IntKeyMap.this.clear();
}
}
/**
* Returns a collection view of the values contained in this map. The
* collection is backed by the map, so changes to the map are reflected in
* the collection, and vice-versa. The collection supports element
* removal, which removes the corresponding mapping from this map, via the
* <tt>Iterator.remove</tt>, <tt>Collection.remove</tt>,
* <tt>removeAll</tt>, <tt>retainAll</tt>, and <tt>clear</tt> operations.
* It does not support the <tt>add</tt> or <tt>addAll</tt> operations.
*
* @return a collection view of the values contained in this map.
*/
@Override
public Collection<VALUE> values() {
Collection<VALUE> vs = values;
return (vs != null ? vs : (values = new Values()));
}
private class Values extends AbstractCollection<VALUE> {
@Override
public Iterator<VALUE> iterator() {
return newValueIterator();
}
@Override
public int size() {
return size;
}
@Override
public boolean contains(Object o) {
return containsValue(o);
}
@Override
public void clear() {
IntKeyMap.this.clear();
}
}
@Override
public Set entrySet()
{
Set<IntEntry<VALUE>> es = entrySet;
return (es != null ? es : (entrySet = new EntrySet()));
}
private class EntrySet extends AbstractSet<IntEntry<VALUE>> {
@Override
public Iterator<IntEntry<VALUE>> iterator() {
return newEntryIterator();
}
@Override
public boolean contains(Object o) {
if (!(o instanceof IntEntry))
return false;
IntEntry<VALUE> e = (IntEntry<VALUE>)o;
IntEntry<VALUE> candidate = getEntry(e.key);
return candidate != null && candidate.equals(e);
}
@Override
public boolean remove(Object o) {
return removeMapping(o) != null;
}
@Override
public int size() {
return size;
}
@Override
public void clear() {
IntKeyMap.this.clear();
}
}
// These methods are used when serializing HashSets
int capacity() { return table.length; }
float loadFactor() { return loadFactor; }
}