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/*
* Copyright 2014-2024 Real Logic Limited.
*
* 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
*
* https://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.agrona.collections;
import org.agrona.generation.DoNotSub;
import java.util.AbstractCollection;
import java.util.AbstractSet;
import java.util.Arrays;
import java.util.Iterator;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.Objects;
import java.util.function.BiConsumer;
import java.util.function.BiFunction;
import java.util.function.IntPredicate;
import java.util.function.ToIntFunction;
import static java.util.Objects.requireNonNull;
import static org.agrona.BitUtil.findNextPositivePowerOfTwo;
import static org.agrona.collections.CollectionUtil.validateLoadFactor;
/**
* {@link java.util.Map} implementation specialised for int values using open addressing and
* linear probing for cache efficient access. The implementation is mirror copy of {@link Int2ObjectHashMap}
* and it also relies on missing value concept from {@link Int2IntHashMap}
*
* @param type of keys stored in the {@link java.util.Map}
*/
public class Object2IntHashMap implements Map
{
@DoNotSub static final int MIN_CAPACITY = 8;
private final float loadFactor;
private final int missingValue;
@DoNotSub private int resizeThreshold;
@DoNotSub private int size;
private final boolean shouldAvoidAllocation;
private K[] keys;
private int[] values;
private ValueCollection valueCollection;
private KeySet keySet;
private EntrySet entrySet;
/**
* Construct a map with default capacity and load factor.
*
* @param missingValue value to be used as a null maker in the map
*/
public Object2IntHashMap(final int missingValue)
{
this(MIN_CAPACITY, Hashing.DEFAULT_LOAD_FACTOR, missingValue);
}
/**
* Construct a new map allowing a configuration for initial capacity and load factor.
*
* @param initialCapacity for the backing array
* @param loadFactor limit for resizing on puts
* @param missingValue value to be used as a null marker in the map
*/
public Object2IntHashMap(
@DoNotSub final int initialCapacity,
final float loadFactor,
final int missingValue)
{
this(initialCapacity, loadFactor, missingValue, true);
}
/**
* Construct a new map allowing a configuration for initial capacity and load factor.
*
* @param initialCapacity for the backing array
* @param loadFactor limit for resizing on puts
* @param missingValue value to be used as a null marker in the map
* @param shouldAvoidAllocation should allocation be avoided by caching iterators and map entries.
*/
@SuppressWarnings("unchecked")
public Object2IntHashMap(
@DoNotSub final int initialCapacity,
final float loadFactor,
final int missingValue,
final boolean shouldAvoidAllocation)
{
validateLoadFactor(loadFactor);
this.loadFactor = loadFactor;
/* @DoNotSub */ final int capacity = findNextPositivePowerOfTwo(Math.max(MIN_CAPACITY, initialCapacity));
/* @DoNotSub */ resizeThreshold = (int)(capacity * loadFactor);
this.missingValue = missingValue;
this.shouldAvoidAllocation = shouldAvoidAllocation;
keys = (K[])new Object[capacity];
values = new int[capacity];
Arrays.fill(values, missingValue);
}
/**
* Copy construct a new map from an existing one.
*
* @param mapToCopy for construction.
*/
public Object2IntHashMap(final Object2IntHashMap mapToCopy)
{
this.loadFactor = mapToCopy.loadFactor;
this.resizeThreshold = mapToCopy.resizeThreshold;
this.size = mapToCopy.size;
this.missingValue = mapToCopy.missingValue;
this.shouldAvoidAllocation = mapToCopy.shouldAvoidAllocation;
keys = mapToCopy.keys.clone();
values = mapToCopy.values.clone();
}
/**
* The value to be used as a null marker in the map.
*
* @return value to be used as a null marker in the map.
*/
public int missingValue()
{
return missingValue;
}
/**
* Get the load factor beyond which the map will increase size.
*
* @return load factor for when the map should increase size.
*/
public float loadFactor()
{
return loadFactor;
}
/**
* Get the total capacity for the map to which the load factor will be a fraction of.
*
* @return the total capacity for the map.
*/
@DoNotSub public int capacity()
{
return values.length;
}
/**
* Get the actual threshold which when reached the map will resize.
* This is a function of the current capacity and load factor.
*
* @return the threshold when the map will resize.
*/
@DoNotSub public int resizeThreshold()
{
return resizeThreshold;
}
/**
* {@inheritDoc}
*/
@DoNotSub public int size()
{
return size;
}
/**
* {@inheritDoc}
*/
public boolean isEmpty()
{
return 0 == size;
}
/**
* {@inheritDoc}
* Overloaded version of {@link Map#containsKey(Object)} that takes a primitive int key.
*
* @param key for indexing the {@link Map}
* @return true if the key is found otherwise false.
*/
@SuppressWarnings("unchecked")
public boolean containsKey(final Object key)
{
return missingValue != getValue((K)key);
}
/**
* {@inheritDoc}
*/
public boolean containsValue(final Object value)
{
return containsValue((int)value);
}
/**
* Overloaded version to avoid boxing.
*
* @param value to check.
* @return true if the collection contains the value.
*/
public boolean containsValue(final int value)
{
if (missingValue == value)
{
return false;
}
boolean found = false;
final int[] values = this.values;
for (final int v : values)
{
if (value == v)
{
found = true;
break;
}
}
return found;
}
/**
* Returns the value to which the specified key is mapped, or {@code defaultValue} if this map contains no mapping
* for the key.
*
* @param key whose associated value is to be returned.
* @param defaultValue the default mapping of the key
* @return the value to which the specified key is mapped, or {@code defaultValue} if this map contains no mapping
* for the key.
*/
@SuppressWarnings("unchecked")
public int getOrDefault(final Object key, final int defaultValue)
{
final int value = getValue((K)key);
return missingValue != value ? value : defaultValue;
}
/**
* {@inheritDoc}
*/
@SuppressWarnings("unchecked")
public Integer get(final Object key)
{
return valueOrNull(getValue((K)key));
}
/**
* Overloaded version of {@link Map#get(Object)} that takes a primitive int key.
* Due to type erasure have to rename the method
*
* @param key for indexing the {@link Map}
* @return the value if found otherwise missingValue
*/
public int getValue(final K key)
{
requireNonNull(key);
final int missingValue = this.missingValue;
final K[] keys = this.keys;
final int[] values = this.values;
@DoNotSub final int mask = values.length - 1;
@DoNotSub int index = Hashing.hash(key, mask);
int value;
while (missingValue != (value = values[index]))
{
if (Objects.equals(keys[index], key))
{
break;
}
index = ++index & mask;
}
return value;
}
/**
* Get a value for a given key, or if it does not exist then default the value via a
* {@link java.util.function.IntFunction} and put it in the map.
*
* Primitive specialized version of {@link java.util.Map#computeIfAbsent}.
*
* @param key to search on.
* @param mappingFunction to provide a value if the get returns missingValue.
* @return old value if found otherwise the newly computed value.
*/
@SuppressWarnings("overloads")
public int computeIfAbsent(final K key, final ToIntFunction mappingFunction)
{
requireNonNull(key);
final int missingValue = this.missingValue;
final K[] keys = this.keys;
final int[] values = this.values;
@DoNotSub final int mask = values.length - 1;
@DoNotSub int index = Hashing.hash(key, mask);
int value;
while (missingValue != (value = values[index]))
{
if (Objects.equals(keys[index], key))
{
return value;
}
index = ++index & mask;
}
final int newValue = mappingFunction.applyAsInt(key);
if (missingValue != newValue)
{
keys[index] = key;
values[index] = newValue;
if (++size > resizeThreshold)
{
increaseCapacity();
}
}
return newValue;
}
/**
* If the value for the specified key is present, attempts to compute a new
* mapping given the key and its current mapped value.
*
* If the function returns missingValue, the mapping is removed
*
* Primitive specialized version of {@link java.util.Map#computeIfPresent(Object, BiFunction)}.
*
* @param key to search on.
* @param remappingFunction to provide a value if the get returns missingValue.
* @return the new value associated with the specified key, or missingValue if none
*/
@SuppressWarnings("overloads")
public int computeIfPresent(final K key, final ObjectIntToIntFunction remappingFunction)
{
requireNonNull(key);
final int missingValue = this.missingValue;
final K[] keys = this.keys;
final int[] values = this.values;
@DoNotSub final int mask = values.length - 1;
@DoNotSub int index = Hashing.hash(key, mask);
int value;
while (missingValue != (value = values[index]))
{
if (Objects.equals(keys[index], key))
{
final int newValue = remappingFunction.apply(key, value);
values[index] = newValue;
if (missingValue == newValue)
{
keys[index] = null;
size--;
compactChain(index);
}
return newValue;
}
index = ++index & mask;
}
return missingValue;
}
/**
* Attempts to compute a mapping for the specified key and its current mapped
* value (or missingValue if there is no current mapping).
*
* If the function returns missingValue, the mapping is removed (or remains
* absent if initially absent).
*
* Primitive specialized version of {@link java.util.Map#compute(Object, BiFunction)}.
*
* @param key to search on.
* @param remappingFunction to provide a value if the get returns missingValue.
* @return the new value associated with the specified key, or missingValue if none
*/
@SuppressWarnings("overloads")
public int compute(final K key, final ObjectIntToIntFunction remappingFunction)
{
requireNonNull(key);
final int missingValue = this.missingValue;
final K[] keys = this.keys;
final int[] values = this.values;
@DoNotSub final int mask = values.length - 1;
@DoNotSub int index = Hashing.hash(key, mask);
int oldValue;
while (missingValue != (oldValue = values[index]))
{
if (Objects.equals(keys[index], key))
{
break;
}
index = ++index & mask;
}
final int newValue = remappingFunction.apply(key, oldValue);
if (missingValue != newValue)
{
values[index] = newValue;
if (missingValue == oldValue)
{
keys[index] = key;
if (++size > resizeThreshold)
{
increaseCapacity();
}
}
}
else if (missingValue != oldValue)
{
keys[index] = null;
values[index] = missingValue;
--size;
compactChain(index);
}
return newValue;
}
/**
* If the specified key is not already associated with a value associates it with the given value. Otherwise,
* replaces the associated value with the results of the given remapping function, or removes if the result is
* {@link #missingValue()}. This method may be of use when combining multiple mapped values for a key. If the
* function returns {@link #missingValue()} the mapping is removed.
*
* Primitive specialized version of {@link java.util.Map#merge(Object, Object, BiFunction)}.
*
* @param key with which the resulting value is to be associated.
* @param value to be merged with the existing value associated with the key or, if no existing value
* is associated with the key, to be associated with the key.
* @param remappingFunction the function to recompute a value if present.
* @return the new value associated with the specified key, or {@link #missingValue()} if no value is associated
* with the key.
*/
public int merge(final K key, final int value, final IntIntFunction remappingFunction)
{
requireNonNull(key);
requireNonNull(remappingFunction);
final int missingValue = this.missingValue;
if (missingValue == value)
{
throw new IllegalArgumentException("cannot accept missingValue");
}
final K[] keys = this.keys;
final int[] values = this.values;
@DoNotSub final int mask = values.length - 1;
@DoNotSub int index = Hashing.hash(key, mask);
int oldValue;
while (missingValue != (oldValue = values[index]))
{
if (Objects.equals(keys[index], key))
{
break;
}
index = ++index & mask;
}
final int newValue = missingValue == oldValue ? value : remappingFunction.apply(oldValue, value);
if (missingValue != newValue)
{
keys[index] = key;
values[index] = newValue;
if (++size > resizeThreshold)
{
increaseCapacity();
}
}
else
{
keys[index] = null;
values[index] = missingValue;
--size;
compactChain(index);
}
return newValue;
}
/**
* {@inheritDoc}
*/
public Integer put(final K key, final Integer value)
{
return valueOrNull(put(key, (int)value));
}
/**
* Overloaded version of {@link Map#put(Object, Object)} that takes a primitive int key.
*
* @param key for indexing the {@link Map}
* @param value to be inserted in the {@link Map}
* @return the previous value if found otherwise missingValue
*/
public int put(final K key, final int value)
{
requireNonNull(key);
final int missingValue = this.missingValue;
if (missingValue == value)
{
throw new IllegalArgumentException("cannot accept missingValue");
}
final K[] keys = this.keys;
final int[] values = this.values;
@DoNotSub final int mask = values.length - 1;
@DoNotSub int index = Hashing.hash(key, mask);
int oldValue;
while (missingValue != (oldValue = values[index]))
{
if (Objects.equals(keys[index], key))
{
break;
}
index = ++index & mask;
}
if (missingValue == oldValue)
{
++size;
keys[index] = key;
}
values[index] = value;
if (size > resizeThreshold)
{
increaseCapacity();
}
return oldValue;
}
/**
* {@inheritDoc}
*/
public Integer putIfAbsent(final K key, final Integer value)
{
return valueOrNull(putIfAbsent(key, (int)value));
}
/**
* If the specified key is not already associated with a value associates it with the given value and returns
* {@link #missingValue()}, else returns the current value.
*
* @param key with which the specified value is to be associated.
* @param value to be associated with the specified key.
* @return the existing value associated with the specified key, or {@link #missingValue()} if there was no mapping
* for the key.
* @throws IllegalArgumentException if {@code value == missingValue()}
*/
public int putIfAbsent(final K key, final int value)
{
requireNonNull(key);
final int missingValue = this.missingValue;
if (missingValue == value)
{
throw new IllegalArgumentException("cannot accept missingValue");
}
final K[] keys = this.keys;
final int[] values = this.values;
@DoNotSub final int mask = values.length - 1;
@DoNotSub int index = Hashing.hash(key, mask);
int oldValue;
while (missingValue != (oldValue = values[index]))
{
if (Objects.equals(keys[index], key))
{
return oldValue;
}
index = ++index & mask;
}
keys[index] = key;
values[index] = value;
if (++size > resizeThreshold)
{
increaseCapacity();
}
return missingValue;
}
/**
* {@inheritDoc}
*/
public boolean remove(final Object key, final Object value)
{
return remove(key, (int)value);
}
/**
* Primitive overload of the {@link Map#remove(Object, Object)} that avoids boxing on the value.
*
* @param key with which the specified value is associated.
* @param value expected to be associated with the specified key.
* @return {@code true} if the value was removed.
*/
public boolean remove(final Object key, final int value)
{
final int missingValue = this.missingValue;
final K[] keys = this.keys;
final int[] values = this.values;
@DoNotSub final int mask = values.length - 1;
@DoNotSub int index = Hashing.hash(key, mask);
int existingValue;
while (missingValue != (existingValue = values[index]))
{
if (Objects.equals(keys[index], key))
{
if (value == existingValue)
{
keys[index] = null;
values[index] = missingValue;
--size;
compactChain(index);
return true;
}
break;
}
index = ++index & mask;
}
return false;
}
/**
* {@inheritDoc}
*/
@SuppressWarnings("unchecked")
public Integer remove(final Object key)
{
return valueOrNull(removeKey(((K)key)));
}
/**
* Overloaded version of {@link Map#remove(Object)} that takes a key and returns a primitive int value.
* Due to type erasure have to rename the method
*
* @param key for indexing the {@link Map}
* @return the value if found otherwise missingValue
*/
public int removeKey(final K key)
{
requireNonNull(key);
final int missingValue = this.missingValue;
final K[] keys = this.keys;
final int[] values = this.values;
@DoNotSub final int mask = values.length - 1;
@DoNotSub int index = Hashing.hash(key, mask);
int value;
while (missingValue != (value = values[index]))
{
if (Objects.equals(keys[index], key))
{
keys[index] = null;
values[index] = missingValue;
--size;
compactChain(index);
break;
}
index = ++index & mask;
}
return value;
}
/**
* {@inheritDoc}
*/
public void clear()
{
if (size > 0)
{
Arrays.fill(keys, null);
Arrays.fill(values, missingValue);
size = 0;
}
}
/**
* Compact the {@link Map} backing arrays by rehashing with a capacity just larger than current size
* and giving consideration to the load factor.
*/
public void compact()
{
@DoNotSub final int idealCapacity = (int)Math.round(size() * (1.0d / loadFactor));
rehash(findNextPositivePowerOfTwo(Math.max(MIN_CAPACITY, idealCapacity)));
}
/**
* {@inheritDoc}
*/
public void putAll(final Map map)
{
for (final Entry entry : map.entrySet())
{
put(entry.getKey(), entry.getValue());
}
}
/**
* Puts all values from the given map to this map.
*
* @param map whose values to be added to this map.
*/
public void putAll(final Object2IntHashMap map)
{
final int missingValue = map.missingValue;
final K[] keys = map.keys;
final int[] values = map.values;
@DoNotSub final int length = values.length;
for (@DoNotSub int index = 0, remaining = map.size; remaining > 0 && index < length; index++)
{
final int value = values[index];
if (missingValue != value)
{
put(keys[index], value);
remaining--;
}
}
}
/**
* {@inheritDoc}
*/
public KeySet keySet()
{
if (null == keySet)
{
keySet = new KeySet();
}
return keySet;
}
/**
* {@inheritDoc}
*/
public ValueCollection values()
{
if (null == valueCollection)
{
valueCollection = new ValueCollection();
}
return valueCollection;
}
/**
* {@inheritDoc}
*/
public EntrySet entrySet()
{
if (null == entrySet)
{
entrySet = new EntrySet();
}
return entrySet;
}
/**
* {@inheritDoc}
*/
public String toString()
{
if (isEmpty())
{
return "{}";
}
final EntryIterator entryIterator = new EntryIterator();
entryIterator.reset();
final StringBuilder sb = new StringBuilder().append('{');
while (true)
{
entryIterator.next();
sb.append(entryIterator.getKey()).append('=').append(entryIterator.getIntValue());
if (!entryIterator.hasNext())
{
return sb.append('}').toString();
}
sb.append(',').append(' ');
}
}
/**
* {@inheritDoc}
*/
public boolean equals(final Object o)
{
if (this == o)
{
return true;
}
if (!(o instanceof Map))
{
return false;
}
final Map that = (Map)o;
if (size != that.size())
{
return false;
}
final K[] keys = this.keys;
final int[] values = this.values;
final int missingValue = this.missingValue;
final int thatMissingValue =
o instanceof Object2IntHashMap ? ((Object2IntHashMap)o).missingValue : missingValue;
for (@DoNotSub int i = 0, length = values.length; i < length; i++)
{
final int thisValue = values[i];
if (missingValue != thisValue)
{
final Object thatValueObject = that.get(keys[i]);
if (!(thatValueObject instanceof Integer))
{
return false;
}
final int thatValue = (Integer)thatValueObject;
if (thatMissingValue == thatValue || thisValue != thatValue)
{
return false;
}
}
}
return true;
}
/**
* {@inheritDoc}
*/
@DoNotSub public int hashCode()
{
@DoNotSub int result = 0;
final K[] keys = this.keys;
final int[] values = this.values;
for (@DoNotSub int i = 0, length = values.length; i < length; i++)
{
final int value = values[i];
if (missingValue != value)
{
result += (keys[i].hashCode() ^ Integer.hashCode(value));
}
}
return result;
}
/**
* Primitive specialised version of {@link Map#replace(Object, Object)}
*
* @param key with which the specified value is associated.
* @param value to be associated with the specified key.
* @return the previous value associated with the specified key, or {@link #missingValue()} if there was no mapping
* for the key.
*/
public int replace(final K key, final int value)
{
requireNonNull(key);
final int missingValue = this.missingValue;
if (missingValue == value)
{
throw new IllegalArgumentException("cannot accept missingValue");
}
final K[] keys = this.keys;
final int[] values = this.values;
@DoNotSub final int mask = values.length - 1;
@DoNotSub int index = Hashing.hash(key, mask);
int existingValue;
while (missingValue != (existingValue = values[index]))
{
if (Objects.equals(keys[index], key))
{
values[index] = value;
return existingValue;
}
index = ++index & mask;
}
return missingValue;
}
/**
* Primitive specialised version of {@link Map#replace(Object, Object, Object)}
*
* @param key key with which the specified value is associated.
* @param oldValue value expected to be associated with the specified key.
* @param newValue value to be associated with the specified key.
* @return {@code true} if the value was replaced.
*/
public boolean replace(final K key, final int oldValue, final int newValue)
{
requireNonNull(key);
final int missingValue = this.missingValue;
if (missingValue == newValue)
{
throw new IllegalArgumentException("cannot accept missingValue");
}
final K[] keys = this.keys;
final int[] values = this.values;
@DoNotSub final int mask = values.length - 1;
@DoNotSub int index = Hashing.hash(key, mask);
int existingValue;
while (missingValue != (existingValue = values[index]))
{
if (Objects.equals(keys[index], key))
{
if (oldValue == existingValue)
{
values[index] = newValue;
return true;
}
break;
}
index = ++index & mask;
}
return false;
}
/**
* Primitive specialised version of {@link Map#replaceAll(BiFunction)}.
*
* NB: Renamed from replaceAll to avoid overloading on parameter types of lambda
* expression, which doesn't play well with type inference in lambda expressions.
*
* @param function the function to apply to each entry.
*/
public void replaceAllInt(final ObjectIntToIntFunction function)
{
requireNonNull(function);
final int missingValue = this.missingValue;
final K[] keys = this.keys;
final int[] values = this.values;
@DoNotSub final int length = values.length;
for (@DoNotSub int index = 0, remaining = size; remaining > 0 && index < length; index++)
{
final int oldValue = values[index];
if (missingValue != oldValue)
{
final int newVal = function.apply(keys[index], oldValue);
if (missingValue == newVal)
{
throw new IllegalArgumentException("cannot accept missingValue");
}
values[index] = newVal;
--remaining;
}
}
}
/**
* {@inheritDoc}
*/
public void forEach(final BiConsumer action)
{
forEachInt(action::accept);
}
/**
* Performs the given action for each entry in this map until all entries have been processed or the action throws
* an exception.
*
* @param action to be performed for each entry.
*/
public void forEachInt(final ObjIntConsumer action)
{
requireNonNull(action);
final int missingValue = this.missingValue;
final K[] keys = this.keys;
final int[] values = this.values;
@DoNotSub final int length = values.length;
for (@DoNotSub int index = 0, remaining = size; remaining > 0 && index < length; index++)
{
final int oldValue = values[index];
if (missingValue != oldValue)
{
action.accept(keys[index], oldValue);
--remaining;
}
}
}
private void increaseCapacity()
{
@DoNotSub final int newCapacity = values.length << 1;
if (newCapacity < 0)
{
throw new IllegalStateException("max capacity reached at size=" + size);
}
rehash(newCapacity);
}
private void rehash(@DoNotSub final int newCapacity)
{
@DoNotSub final int mask = newCapacity - 1;
/* @DoNotSub */ resizeThreshold = (int)(newCapacity * loadFactor);
@SuppressWarnings("unchecked")
final K[] tempKeys = (K[])new Object[newCapacity];
final int[] tempValues = new int[newCapacity];
Arrays.fill(tempValues, missingValue);
final K[] keys = this.keys;
final int[] values = this.values;
for (@DoNotSub int i = 0, size = values.length; i < size; i++)
{
final int value = values[i];
if (missingValue != value)
{
final K key = keys[i];
@DoNotSub int index = Hashing.hash(key, mask);
while (missingValue != tempValues[index])
{
index = ++index & mask;
}
tempKeys[index] = key;
tempValues[index] = value;
}
}
this.keys = tempKeys;
this.values = tempValues;
}
@SuppressWarnings("FinalParameters")
private void compactChain(@DoNotSub int deleteIndex)
{
final K[] keys = this.keys;
final int[] values = this.values;
@DoNotSub final int mask = values.length - 1;
@DoNotSub int index = deleteIndex;
while (true)
{
index = ++index & mask;
final int value = values[index];
if (missingValue == value)
{
break;
}
final K key = keys[index];
@DoNotSub final int hash = Hashing.hash(key, mask);
if ((index < hash && (hash <= deleteIndex || deleteIndex <= index)) ||
(hash <= deleteIndex && deleteIndex <= index))
{
keys[deleteIndex] = key;
values[deleteIndex] = value;
keys[index] = null;
values[index] = missingValue;
deleteIndex = index;
}
}
}
private Integer valueOrNull(final int value)
{
return value == missingValue ? null : value;
}
/**
* Set of keys that can optionally cache iterators to avoid allocation.
*/
public final class KeySet extends AbstractSet
{
private final KeyIterator keyIterator = shouldAvoidAllocation ? new KeyIterator() : null;
/**
* {@inheritDoc}
*/
public KeyIterator iterator()
{
KeyIterator keyIterator = this.keyIterator;
if (null == keyIterator)
{
keyIterator = new KeyIterator();
}
keyIterator.reset();
return keyIterator;
}
/**
* {@inheritDoc}
*/
@DoNotSub public int size()
{
return Object2IntHashMap.this.size();
}
/**
* {@inheritDoc}
*/
public boolean contains(final Object o)
{
return Object2IntHashMap.this.containsKey(o);
}
/**
* {@inheritDoc}
*/
@SuppressWarnings("unchecked")
public boolean remove(final Object o)
{
return missingValue != Object2IntHashMap.this.removeKey((K)o);
}
/**
* {@inheritDoc}
*/
public void clear()
{
Object2IntHashMap.this.clear();
}
}
/**
* Collection of values which can optionally cache iterators to avoid allocation.
*/
public final class ValueCollection extends AbstractCollection
{
private final ValueIterator valueIterator = shouldAvoidAllocation ? new ValueIterator() : null;
/**
* {@inheritDoc}
*/
public ValueIterator iterator()
{
ValueIterator valueIterator = this.valueIterator;
if (null == valueIterator)
{
valueIterator = new ValueIterator();
}
valueIterator.reset();
return valueIterator;
}
/**
* {@inheritDoc}
*/
@DoNotSub public int size()
{
return Object2IntHashMap.this.size();
}
/**
* {@inheritDoc}
*/
public boolean contains(final Object o)
{
return containsValue(o);
}
/**
* Checks if the value is contained in the map.
*
* @param value to be checked.
* @return {@code true} if value is contained in this map.
*/
public boolean contains(final int value)
{
return containsValue(value);
}
/**
* {@inheritDoc}
*/
public void clear()
{
Object2IntHashMap.this.clear();
}
/**
* Removes all the elements of this collection that satisfy the given predicate.
*
* @param filter a predicate which returns {@code true} for elements to be removed.
* @return {@code true} if any elements were removed.
*/
public boolean removeIfInt(final IntPredicate filter)
{
boolean removed = false;
final ValueIterator iterator = iterator();
while (iterator.hasNext())
{
if (filter.test(iterator.nextInt()))
{
iterator.remove();
removed = true;
}
}
return removed;
}
}
/**
* Set of entries which can optionally cache iterators to avoid allocation.
*/
public final class EntrySet extends AbstractSet>
{
private final EntryIterator entryIterator = shouldAvoidAllocation ? new EntryIterator() : null;
/**
* {@inheritDoc}
*/
public EntryIterator iterator()
{
EntryIterator entryIterator = this.entryIterator;
if (null == entryIterator)
{
entryIterator = new EntryIterator();
}
entryIterator.reset();
return entryIterator;
}
/**
* {@inheritDoc}
*/
@DoNotSub public int size()
{
return Object2IntHashMap.this.size();
}
/**
* {@inheritDoc}
*/
public void clear()
{
Object2IntHashMap.this.clear();
}
/**
* {@inheritDoc}
*/
public boolean contains(final Object o)
{
if (!(o instanceof Entry))
{
return false;
}
@SuppressWarnings("rawtypes") final Entry entry = (Entry)o;
final Integer value = get(entry.getKey());
return value != null && value.equals(entry.getValue());
}
/**
* Removes all the elements of this collection that satisfy the given predicate.
*
* @param filter a predicate which returns {@code true} for elements to be removed.
* @return {@code true} if any elements were removed.
*/
public boolean removeIfInt(final ObjIntPredicate filter)
{
boolean removed = false;
final EntryIterator iterator = iterator();
while (iterator.hasNext())
{
iterator.findNext();
if (filter.test(iterator.getKey(), iterator.getIntValue()))
{
iterator.remove();
removed = true;
}
}
return removed;
}
/**
* {@inheritDoc}
*/
public Object[] toArray()
{
return toArray(new Object[size()]);
}
/**
* {@inheritDoc}
*/
@SuppressWarnings("unchecked")
public T[] toArray(final T[] a)
{
final T[] array = a.length >= size ?
a : (T[])java.lang.reflect.Array.newInstance(a.getClass().getComponentType(), size);
final EntryIterator it = iterator();
for (@DoNotSub int i = 0; i < array.length; i++)
{
if (it.hasNext())
{
it.next();
array[i] = (T)it.allocateDuplicateEntry();
}
else
{
array[i] = null;
break;
}
}
return array;
}
}
/**
* Base iterator implementation that contains basic logic of traversing the element in the backing array.
*
* @param type of elements.
*/
abstract class AbstractIterator implements Iterator
{
@DoNotSub private int posCounter;
@DoNotSub private int stopCounter;
@DoNotSub private int remaining;
private boolean isPositionValid = false;
/**
* Position of the current element.
*
* @return position of the element in the array.
*/
@DoNotSub protected final int position()
{
return posCounter & (values.length - 1);
}
/**
* {@inheritDoc}
*/
public boolean hasNext()
{
return remaining > 0;
}
/**
* Find next element.
*
* @throws NoSuchElementException if no more elements.
*/
protected final void findNext()
{
if (!hasNext())
{
throw new NoSuchElementException();
}
final int missingValue = Object2IntHashMap.this.missingValue;
final int[] values = Object2IntHashMap.this.values;
@DoNotSub final int mask = values.length - 1;
for (@DoNotSub int i = posCounter - 1; i >= stopCounter; i--)
{
@DoNotSub final int index = i & mask;
if (missingValue != values[index])
{
posCounter = i;
isPositionValid = true;
--remaining;
return;
}
}
isPositionValid = false;
throw new IllegalStateException();
}
/**
* {@inheritDoc}
*/
public abstract T next();
/**
* {@inheritDoc}
*/
public void remove()
{
if (isPositionValid)
{
@DoNotSub final int position = position();
values[position] = missingValue;
keys[position] = null;
--size;
compactChain(position);
isPositionValid = false;
}
else
{
throw new IllegalStateException();
}
}
final void reset()
{
remaining = Object2IntHashMap.this.size;
final int[] values = Object2IntHashMap.this.values;
@DoNotSub final int capacity = values.length;
@DoNotSub int i = capacity;
if (missingValue != values[capacity - 1])
{
for (i = 0; i < capacity; i++)
{
if (missingValue == values[i])
{
break;
}
}
}
stopCounter = i;
posCounter = i + capacity;
isPositionValid = false;
}
}
/**
* Iterator over values providing unboxed access via {@link #nextInt()}.
*/
public final class ValueIterator extends AbstractIterator
{
/**
* {@inheritDoc}
*/
public Integer next()
{
return nextInt();
}
/**
* Get next value without boxing.
*
* @return next value.
*/
public int nextInt()
{
findNext();
return values[position()];
}
}
/**
* Iterator over keys.
*/
public final class KeyIterator extends AbstractIterator
{
/**
* {@inheritDoc}
*/
public K next()
{
findNext();
return keys[position()];
}
}
/**
* Iterator over entries which can provide unboxed access and optionally avoid allocation.
*/
public final class EntryIterator
extends AbstractIterator>
implements Entry
{
/**
* {@inheritDoc}
*/
public Entry next()
{
findNext();
if (shouldAvoidAllocation)
{
return this;
}
return allocateDuplicateEntry();
}
private Entry allocateDuplicateEntry()
{
return new MapEntry(getKey(), getIntValue());
}
/**
* {@inheritDoc}
*/
public K getKey()
{
return keys[position()];
}
/**
* Get int value without boxing.
*
* @return value.
*/
public int getIntValue()
{
return values[position()];
}
/**
* {@inheritDoc}
*/
public Integer getValue()
{
return getIntValue();
}
/**
* {@inheritDoc}
*/
public Integer setValue(final Integer value)
{
return setValue((int)value);
}
/**
* Set value at current position without boxing.
*
* @param value to be set.
* @return old value.
* @throws IllegalArgumentException if {@code missingValue == value}.
*/
public int setValue(final int value)
{
if (missingValue == value)
{
throw new IllegalArgumentException("cannot accept missingValue");
}
@DoNotSub final int pos = position();
final int oldValue = values[pos];
values[pos] = value;
return oldValue;
}
/**
* {@inheritDoc}
*/
@DoNotSub public int hashCode()
{
return getKey().hashCode() ^ Integer.hashCode(getIntValue());
}
/**
* {@inheritDoc}
*/
public boolean equals(final Object o)
{
if (this == o)
{
return true;
}
if (!(o instanceof Entry))
{
return false;
}
final Entry e = (Entry)o;
return Objects.equals(getKey(), e.getKey()) && e.getValue() instanceof Integer &&
getIntValue() == (Integer)e.getValue();
}
/**
* An {@link java.util.Map.Entry} implementation.
*/
public final class MapEntry implements Entry
{
private final K k;
private int v;
/**
* @param k key.
* @param v value.
*/
public MapEntry(final K k, final int v)
{
this.k = k;
this.v = v;
}
/**
* {@inheritDoc}
*/
public K getKey()
{
return k;
}
/**
* {@inheritDoc}
*/
public Integer getValue()
{
return v;
}
/**
* {@inheritDoc}
*/
public Integer setValue(final Integer value)
{
final Integer oldValue = Object2IntHashMap.this.put(k, value);
v = value;
return oldValue;
}
/**
* {@inheritDoc}
*/
@DoNotSub public int hashCode()
{
return getKey().hashCode() ^ Integer.hashCode(v);
}
/**
* {@inheritDoc}
*/
public boolean equals(final Object o)
{
if (this == o)
{
return true;
}
if (!(o instanceof Entry))
{
return false;
}
final Entry e = (Entry)o;
return Objects.equals(getKey(), e.getKey()) && e.getValue() instanceof Integer &&
v == (Integer)e.getValue();
}
/**
* {@inheritDoc}
*/
public String toString()
{
return k + "=" + v;
}
}
}
}