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/*
* Copyright (c) 2015, Haiyang Li.
*
* 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 com.landawn.abacus.util;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Comparator;
import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.Set;
import com.landawn.abacus.annotation.Internal;
import com.landawn.abacus.util.Fn.Suppliers;
import com.landawn.abacus.util.If.OrElse;
import com.landawn.abacus.util.u.Optional;
import com.landawn.abacus.util.u.OptionalDouble;
import com.landawn.abacus.util.function.Function;
import com.landawn.abacus.util.function.IntFunction;
import com.landawn.abacus.util.function.Supplier;
import com.landawn.abacus.util.stream.EntryStream;
import com.landawn.abacus.util.stream.Stream;
/**
* A collection that supports order-independent equality, like {@link Set}, but
* may have duplicate elements.
*
* Elements of a Multiset that are equal to one another are referred to as
* occurrences of the same single element. The total number of
* occurrences of an element in a Multiset is called the count of that
* element (the terms "frequency" and "multiplicity" are equivalent, but not
* used in this API). Since the count of an element is represented as an {@code
* int}, a Multiset may never contain more than {@link MutableInt#MAX_VALUE}
* occurrences of any one element.
*
* @author Haiyang Li
* @param
* @since 0.8
*/
public final class Multiset implements Iterable {
private static final Comparator> cmpByCount = (a, b) -> N.compare(a.getValue().value(), b.getValue().value());
final Supplier> mapSupplier;
final Map valueMap;
public Multiset() {
this(HashMap.class);
}
public Multiset(int initialCapacity) {
this.mapSupplier = Suppliers.ofMap();
this.valueMap = N.newHashMap(initialCapacity);
}
public Multiset(final Collection c) {
this((c == null || c instanceof Set) ? N.size(c) : N.size(c) / 2);
addAll(c);
}
@SuppressWarnings("rawtypes")
public Multiset(final Class valueMapType) {
this(Maps.mapType2Supplier(valueMapType));
}
@SuppressWarnings("rawtypes")
public Multiset(final Supplier> mapSupplier) {
this.mapSupplier = (Supplier) mapSupplier;
this.valueMap = this.mapSupplier.get();
}
@Internal
Multiset(final Map valueMap) {
this.mapSupplier = Maps.mapType2Supplier(valueMap.getClass());
this.valueMap = valueMap;
}
/**
*
* @param
* @param a
* @return
*/
@SafeVarargs
public static Multiset of(final T... a) {
if (N.isNullOrEmpty(a)) {
return new Multiset<>();
}
final Multiset multiset = new Multiset<>(N. newHashMap(a.length));
for (T e : a) {
multiset.add(e);
}
return multiset;
}
/**
*
* @param
* @param coll
* @return
*/
public static Multiset from(final Collection coll) {
return new Multiset<>(coll);
}
/**
*
* @param
* @param iter
* @return
*/
public static Multiset from(final Iterator iter) {
final Multiset result = new Multiset<>();
if (iter != null) {
T e = null;
MutableInt count = null;
while (iter.hasNext()) {
e = iter.next();
count = result.valueMap.get(e);
if (count == null) {
result.valueMap.put(e, MutableInt.of(1));
} else {
if (count.value() == Integer.MAX_VALUE) {
throw new IllegalArgumentException("The total count is out of the bound of int");
}
count.add(1);
}
}
}
return result;
}
/**
*
* @param
* @param m
* @return
*/
public static Multiset from(final Map m) {
if (N.isNullOrEmpty(m)) {
return new Multiset<>();
}
final Multiset multiset = new Multiset<>(Maps.newTargetMap(m));
multiset.setAll(m);
return multiset;
}
/**
*
* @param e
* @return
*/
public int get(final Object e) {
final MutableInt count = valueMap.get(e);
return count == null ? 0 : count.value();
}
/**
* Gets the or default.
*
* @param e
* @param defaultValue
* @return
*/
public int getOrDefault(final Object e, int defaultValue) {
final MutableInt count = valueMap.get(e);
return count == null ? defaultValue : count.value();
}
/**
* The element will be removed if the specified count is 0.
*
* @param e
* @param occurrences
* @return
*/
public int getAndSet(final T e, final int occurrences) {
checkOccurrences(occurrences);
final MutableInt count = valueMap.get(e);
int result = count == null ? 0 : count.value();
if (occurrences == 0) {
if (count != null) {
valueMap.remove(e);
}
} else {
if (count == null) {
valueMap.put(e, MutableInt.of(occurrences));
} else {
count.setValue(occurrences);
}
}
return result;
}
/**
* The element will be removed if the specified count is 0.
*
* @param e
* @param occurrences
* @return
*/
public int setAndGet(final T e, final int occurrences) {
checkOccurrences(occurrences);
final MutableInt count = valueMap.get(e);
if (occurrences == 0) {
if (count != null) {
valueMap.remove(e);
}
} else {
if (count == null) {
valueMap.put(e, MutableInt.of(occurrences));
} else {
count.setValue(occurrences);
}
}
return occurrences;
}
/**
* The element will be removed if the specified count is 0.
*
* @param e
* @param occurrences
* @return this Multiset.
* @throws IllegalArgumentException if the occurrences of element is less than 0
*/
public Multiset set(final T e, final int occurrences) {
checkOccurrences(occurrences);
if (occurrences == 0) {
valueMap.remove(e);
} else {
final MutableInt count = valueMap.get(e);
if (count == null) {
valueMap.put(e, MutableInt.of(occurrences));
} else {
count.setValue(occurrences);
}
}
return this;
}
/**
* Sets the all.
*
* @param c
* @param occurrences
* @return
*/
public Multiset setAll(final Collection c, final int occurrences) {
checkOccurrences(occurrences);
if (N.notNullOrEmpty(c)) {
for (T e : c) {
set(e, occurrences);
}
}
return this;
}
/**
* Sets the all.
*
* @param m
* @return this Multiset.
* @throws IllegalArgumentException if the occurrences of element is less than 0.
*/
public Multiset setAll(final Map m) throws IllegalArgumentException {
if (N.notNullOrEmpty(m)) {
for (Map.Entry entry : m.entrySet()) {
checkOccurrences(entry.getValue());
}
for (Map.Entry entry : m.entrySet()) {
set(entry.getKey(), entry.getValue().intValue());
}
}
return this;
}
/**
* Sets the all.
*
* @param multiset
* @return this Multiset.
* @throws IllegalArgumentException if the occurrences of element is less than 0.
*/
public Multiset setAll(final Multiset multiset) throws IllegalArgumentException {
if (N.notNullOrEmpty(multiset)) {
for (Map.Entry entry : multiset.valueMap.entrySet()) {
set(entry.getKey(), entry.getValue().value());
}
}
return this;
}
/**
*
* @param e
* @return
*/
public int occurrencesOf(final Object e) {
return get(e);
}
public Optional> minOccurrences() {
if (size() == 0) {
return Optional.empty();
}
final Iterator> it = valueMap.entrySet().iterator();
Map.Entry entry = it.next();
T minCountElement = entry.getKey();
int minCount = entry.getValue().value();
while (it.hasNext()) {
entry = it.next();
if (entry.getValue().value() < minCount) {
minCountElement = entry.getKey();
minCount = entry.getValue().value();
}
}
return Optional.of(Pair.of(minCountElement, minCount));
}
public Optional> maxOccurrences() {
if (size() == 0) {
return Optional.empty();
}
final Iterator> it = valueMap.entrySet().iterator();
Map.Entry entry = it.next();
T maxCountElement = entry.getKey();
int maxCount = entry.getValue().value();
while (it.hasNext()) {
entry = it.next();
if (entry.getValue().value() > maxCount) {
maxCountElement = entry.getKey();
maxCount = entry.getValue().value();
}
}
return Optional.of(Pair.of(maxCountElement, maxCount));
}
/**
* All min occurrences.
*
* @return
*/
public Optional, Integer>> allMinOccurrences() {
if (size() == 0) {
return Optional.empty();
}
int min = Integer.MAX_VALUE;
for (MutableInt e : valueMap.values()) {
if (e.value() < min) {
min = e.value();
}
}
final List res = new ArrayList<>();
for (Map.Entry entry : valueMap.entrySet()) {
if (entry.getValue().value() == min) {
res.add(entry.getKey());
}
}
return Optional.of(Pair.of(res, min));
}
/**
* All max occurrences.
*
* @return
*/
public Optional, Integer>> allMaxOccurrences() {
if (size() == 0) {
return Optional.empty();
}
int max = Integer.MIN_VALUE;
for (MutableInt e : valueMap.values()) {
if (e.value() > max) {
max = e.value();
}
}
final List res = new ArrayList<>();
for (Map.Entry entry : valueMap.entrySet()) {
if (entry.getValue().value() == max) {
res.add(entry.getKey());
}
}
return Optional.of(Pair.of(res, max));
}
/**
* Sum of occurrences.
*
* @return
* @throws ArithmeticException if total occurrences overflows the maximum value of int.
*/
public long sumOfOccurrences() {
long sum = 0;
for (MutableInt count : valueMap.values()) {
sum = Numbers.addExact(sum, count.value());
}
return sum;
}
/**
* Average of occurrences.
*
* @return
*/
public OptionalDouble averageOfOccurrences() {
if (size() == 0) {
return OptionalDouble.empty();
}
final double sum = sumOfOccurrences();
return OptionalDouble.of(sum / size());
}
/**
*
* @param e
* @return always true
* @throws IllegalArgumentException if the occurrences of element after this operation is bigger than Integer.MAX_VALUE.
*/
public boolean add(final T e) throws IllegalArgumentException {
return add(e, 1);
}
/**
*
* @param e
* @param occurrencesToAdd
* @return true if the specified occurrences is bigger than 0.
* @throws IllegalArgumentException if the occurrences of element after this operation is bigger than Integer.MAX_VALUE.
*/
public boolean add(final T e, final int occurrencesToAdd) throws IllegalArgumentException {
checkOccurrences(occurrencesToAdd);
MutableInt count = valueMap.get(e);
if (count != null && occurrencesToAdd > (Integer.MAX_VALUE - count.value())) {
throw new IllegalArgumentException("The total count is out of the bound of int");
}
if (count == null) {
if (occurrencesToAdd > 0) {
count = MutableInt.of(occurrencesToAdd);
valueMap.put(e, count);
}
} else {
count.add(occurrencesToAdd);
}
return occurrencesToAdd > 0;
}
/**
* Adds the if absent.
*
* @param e
* @return true if the specified element is absent.
* @throws IllegalArgumentException the illegal argument exception
*/
public boolean addIfAbsent(final T e) throws IllegalArgumentException {
return addIfAbsent(e, 1);
}
/**
* Adds the if absent.
*
* @param e
* @param occurrencesToAdd
* @return true if the specified element is absent and occurrences is bigger than 0.
* @throws IllegalArgumentException the illegal argument exception
*/
public boolean addIfAbsent(final T e, final int occurrencesToAdd) throws IllegalArgumentException {
checkOccurrences(occurrencesToAdd);
MutableInt count = valueMap.get(e);
if (count == null && occurrencesToAdd > 0) {
count = MutableInt.of(occurrencesToAdd);
valueMap.put(e, count);
return true;
}
return false;
}
/**
* Adds the and get.
*
* @param e
* @return
*/
public int addAndGet(final T e) {
return addAndGet(e, 1);
}
/**
* Adds the and get.
*
* @param e
* @param occurrencesToAdd
* @return
*/
public int addAndGet(final T e, final int occurrencesToAdd) {
checkOccurrences(occurrencesToAdd);
MutableInt count = valueMap.get(e);
if (count != null && occurrencesToAdd > (Integer.MAX_VALUE - count.value())) {
throw new IllegalArgumentException("The total count is out of the bound of int");
}
if (count == null) {
if (occurrencesToAdd > 0) {
count = MutableInt.of(occurrencesToAdd);
valueMap.put(e, count);
}
} else {
count.add(occurrencesToAdd);
}
return count == null ? 0 : count.value();
}
/**
* Gets the and add.
*
* @param e
* @return
*/
public int getAndAdd(final T e) {
return getAndAdd(e, 1);
}
/**
* Gets the and add.
*
* @param e
* @param occurrencesToAdd
* @return
*/
public int getAndAdd(final T e, final int occurrencesToAdd) {
checkOccurrences(occurrencesToAdd);
MutableInt count = valueMap.get(e);
if (count != null && occurrencesToAdd > (Integer.MAX_VALUE - count.value())) {
throw new IllegalArgumentException("The total count is out of the bound of int");
}
final int result = count == null ? 0 : count.value();
if (count == null) {
if (occurrencesToAdd > 0) {
count = MutableInt.of(occurrencesToAdd);
valueMap.put(e, count);
}
} else {
count.add(occurrencesToAdd);
}
return result;
}
/**
* Adds the all.
*
* @param c
* @return
* @throws IllegalArgumentException if the occurrences of element after this operation is bigger than Integer.MAX_VALUE.
*/
public boolean addAll(final Collection c) throws IllegalArgumentException {
if (N.isNullOrEmpty(c)) {
return false;
}
return addAll(c, 1);
}
/**
* Adds the all.
*
* @param c
* @param occurrencesToAdd
* @return
* @throws IllegalArgumentException if the occurrences of element after this operation is bigger than Integer.MAX_VALUE.
*/
public boolean addAll(final Collection c, final int occurrencesToAdd) throws IllegalArgumentException {
checkOccurrences(occurrencesToAdd);
if (N.isNullOrEmpty(c) || occurrencesToAdd == 0) {
return false;
}
for (T e : c) {
add(e, occurrencesToAdd);
}
return occurrencesToAdd > 0;
}
/**
* Adds the all.
*
* @param m
* @return
* @throws IllegalArgumentException if the occurrences of element after this operation is bigger than Integer.MAX_VALUE.
*/
public boolean addAll(final Map m) throws IllegalArgumentException {
if (N.isNullOrEmpty(m)) {
return false;
}
for (Map.Entry entry : m.entrySet()) {
checkOccurrences(entry.getValue());
}
boolean result = false;
for (Map.Entry entry : m.entrySet()) {
if (!result) {
result = add(entry.getKey(), entry.getValue().intValue());
} else {
add(entry.getKey(), entry.getValue().intValue());
}
}
return result;
}
/**
* Adds the all.
*
* @param multiset
* @return
* @throws IllegalArgumentException if the occurrences of element is less than 0.
*/
public boolean addAll(final Multiset multiset) throws IllegalArgumentException {
if (N.isNullOrEmpty(multiset)) {
return false;
}
for (Map.Entry entry : multiset.valueMap.entrySet()) {
add(entry.getKey(), entry.getValue().value());
}
return true;
}
/**
*
* @param o
* @return
*/
public boolean contains(final Object o) {
return valueMap.containsKey(o);
}
/**
*
* @param c
* @return
*/
public boolean containsAll(final Collection c) {
return valueMap.keySet().containsAll(c);
}
/**
* Remove one occurrence from the specified elements.
* The element will be removed from this Multiset if the occurrences equals to or less than 0 after the operation.
*
* @param e
* @return
*/
public boolean remove(final Object e) {
return remove(e, 1);
}
/**
* Remove the specified occurrences from the specified element.
* The element will be removed from this Multiset if the occurrences equals to or less than 0 after the operation.
*
* @param e
* @param occurrencesToRemove
* @return
*/
public boolean remove(final Object e, final int occurrencesToRemove) {
checkOccurrences(occurrencesToRemove);
final MutableInt count = valueMap.get(e);
if (count == null) {
return false;
} else {
count.subtract(occurrencesToRemove);
if (count.value() <= 0) {
valueMap.remove(e);
}
return occurrencesToRemove > 0;
}
}
/**
* Removes the and get.
*
* @param e
* @return
*/
public int removeAndGet(final Object e) {
return removeAndGet(e, 1);
}
/**
* Removes the and get.
*
* @param e
* @param occurrencesToRemove
* @return
*/
public int removeAndGet(final Object e, final int occurrencesToRemove) {
checkOccurrences(occurrencesToRemove);
final MutableInt count = valueMap.get(e);
if (count == null) {
return 0;
} else {
count.subtract(occurrencesToRemove);
if (count.value() <= 0) {
valueMap.remove(e);
}
return count.value() > 0 ? count.value() : 0;
}
}
/**
* Gets the and remove.
*
* @param e
* @return
*/
public int getAndRemove(final Object e) {
return getAndRemove(e, 1);
}
/**
* Gets the and remove.
*
* @param e
* @param occurrencesToRemove
* @return
*/
public int getAndRemove(final Object e, final int occurrencesToRemove) {
checkOccurrences(occurrencesToRemove);
final MutableInt count = valueMap.get(e);
final int result = count == null ? 0 : count.value();
if (count != null) {
count.subtract(occurrencesToRemove);
if (count.value() <= 0) {
valueMap.remove(e);
}
}
return result;
}
/**
* Removes the all occurrences.
*
* @param e
* @return
*/
public int removeAllOccurrences(final Object e) {
final MutableInt count = valueMap.remove(e);
return count == null ? 0 : count.value();
}
/**
* Removes the all occurrences if.
*
* @param
* @param predicate
* @return
* @throws E the e
*/
public boolean removeAllOccurrencesIf(Throwables.Predicate predicate) throws E {
Set removingKeys = null;
for (T key : this.valueMap.keySet()) {
if (predicate.test(key)) {
if (removingKeys == null) {
removingKeys = N.newHashSet();
}
removingKeys.add(key);
}
}
if (N.isNullOrEmpty(removingKeys)) {
return false;
}
removeAll(removingKeys);
return true;
}
/**
* Removes the all occurrences if.
*
* @param
* @param predicate
* @return
* @throws E the e
*/
public boolean removeAllOccurrencesIf(Throwables.BiPredicate predicate) throws E {
Set removingKeys = null;
for (Map.Entry entry : this.valueMap.entrySet()) {
if (predicate.test(entry.getKey(), entry.getValue().value())) {
if (removingKeys == null) {
removingKeys = N.newHashSet();
}
removingKeys.add(entry.getKey());
}
}
if (N.isNullOrEmpty(removingKeys)) {
return false;
}
removeAll(removingKeys);
return true;
}
/**
* Removes the if.
*
* @param
* @param occurrencesToRemove
* @param predicate
* @return
* @throws E the e
*/
public boolean removeIf(final int occurrencesToRemove, Throwables.Predicate predicate) throws E {
checkOccurrences(occurrencesToRemove);
Set removingKeys = null;
for (T key : this.valueMap.keySet()) {
if (predicate.test(key)) {
if (removingKeys == null) {
removingKeys = N.newHashSet();
}
removingKeys.add(key);
}
}
if (N.isNullOrEmpty(removingKeys)) {
return false;
}
removeAll(removingKeys, occurrencesToRemove);
return true;
}
/**
* Removes the if.
*
* @param
* @param occurrencesToRemove
* @param predicate
* @return
* @throws E the e
*/
public boolean removeIf(final int occurrencesToRemove, Throwables.BiPredicate predicate) throws E {
checkOccurrences(occurrencesToRemove);
Set removingKeys = null;
for (Map.Entry entry : this.valueMap.entrySet()) {
if (predicate.test(entry.getKey(), entry.getValue().value())) {
if (removingKeys == null) {
removingKeys = N.newHashSet();
}
removingKeys.add(entry.getKey());
}
}
if (N.isNullOrEmpty(removingKeys)) {
return false;
}
removeAll(removingKeys, occurrencesToRemove);
return true;
}
/**
* Removes all of this Multiset's elements that are also contained in the
* specified collection (optional operation). After this call returns,
* this Multiset will contain no elements in common with the specified
* collection. This method ignores how often any element might appear in
* {@code c}, and only cares whether or not an element appears at all.
*
* @param c
* @return true if this set changed as a result of the call
* @see Collection#removeAll(Collection)
*/
public boolean removeAll(final Collection c) {
if (N.isNullOrEmpty(c)) {
return false;
}
boolean result = false;
for (Object e : c) {
if (!result) {
result = valueMap.remove(e) != null;
} else {
valueMap.remove(e);
}
}
return result;
}
/**
* Remove the specified occurrences from the specified elements.
* The elements will be removed from this set if the occurrences equals to or less than 0 after the operation.
*
* @param c
* @param occurrencesToRemove the occurrences to remove if the element is in the specified collection c.
* @return true if this set changed as a result of the call
* @deprecated
*/
@Deprecated
public boolean removeAll(final Collection c, final int occurrencesToRemove) {
checkOccurrences(occurrencesToRemove);
if (N.isNullOrEmpty(c) || occurrencesToRemove == 0) {
return false;
}
boolean result = false;
for (Object e : c) {
if (!result) {
result = remove(e, occurrencesToRemove);
} else {
remove(e, occurrencesToRemove);
}
}
return result;
}
/**
* Removes the all.
*
* @param m
* @return
*/
public boolean removeAll(final Map m) {
if (N.isNullOrEmpty(m)) {
return false;
}
for (Map.Entry entry : m.entrySet()) {
checkOccurrences(entry.getValue());
}
boolean result = false;
for (Map.Entry entry : m.entrySet()) {
if (!result) {
result = remove(entry.getKey(), entry.getValue().intValue());
} else {
remove(entry.getKey(), entry.getValue().intValue());
}
}
return result;
}
/**
* Removes the all.
*
* @param multiset
* @return
* @throws IllegalArgumentException the illegal argument exception
*/
public boolean removeAll(final Multiset multiset) throws IllegalArgumentException {
if (N.isNullOrEmpty(multiset)) {
return false;
}
for (Map.Entry entry : multiset.valueMap.entrySet()) {
remove(entry.getKey(), entry.getValue().value());
}
return true;
}
/**
*
* @param
* @param predicate
* @param newOccurrences
* @return
* @throws E the e
*/
public boolean replaceIf(Throwables.Predicate predicate, final int newOccurrences) throws E {
checkOccurrences(newOccurrences);
boolean modified = false;
if (newOccurrences == 0) {
final List keysToRemove = new ArrayList<>();
for (T key : valueMap.keySet()) {
if (predicate.test(key)) {
keysToRemove.add(key);
}
}
if (keysToRemove.size() > 0) {
for (T key : keysToRemove) {
valueMap.remove(key);
}
modified = true;
}
} else {
for (Map.Entry entry : valueMap.entrySet()) {
if (predicate.test(entry.getKey())) {
entry.getValue().setValue(newOccurrences);
modified = true;
}
}
}
return modified;
}
/**
*
* @param
* @param predicate
* @param newOccurrences
* @return
* @throws E the e
*/
public boolean replaceIf(Throwables.BiPredicate predicate, final int newOccurrences) throws E {
checkOccurrences(newOccurrences);
boolean modified = false;
if (newOccurrences == 0) {
final List keysToRemove = new ArrayList<>();
for (Map.Entry entry : valueMap.entrySet()) {
if (predicate.test(entry.getKey(), entry.getValue().value())) {
keysToRemove.add(entry.getKey());
}
}
if (keysToRemove.size() > 0) {
for (T key : keysToRemove) {
valueMap.remove(key);
}
modified = true;
}
} else {
for (Map.Entry entry : valueMap.entrySet()) {
if (predicate.test(entry.getKey(), entry.getValue().value())) {
entry.getValue().setValue(newOccurrences);
modified = true;
}
}
}
return modified;
}
/**
* The associated elements will be removed if zero or negative occurrences are returned by the specified function.
*
* @param
* @param function
* @throws E the e
*/
public void replaceAll(Throwables.BiFunction function) throws E {
List keyToRemove = null;
Integer newVal = null;
for (Map.Entry entry : this.valueMap.entrySet()) {
newVal = function.apply(entry.getKey(), entry.getValue().value());
if (newVal == null || newVal.intValue() <= 0) {
if (keyToRemove == null) {
keyToRemove = new ArrayList<>();
}
keyToRemove.add(entry.getKey());
} else {
entry.getValue().setValue(newVal);
}
}
if (N.notNullOrEmpty(keyToRemove)) {
for (T key : keyToRemove) {
valueMap.remove(key);
}
}
}
/**
* Retains only the elements in this collection that are contained in the
* specified collection (optional operation). In other words, removes from
* this collection all of its elements that are not contained in the
* specified collection.
*
* @param c
* @return true if this set changed as a result of the call
* @see Collection#retainAll(Collection)
*/
public boolean retainAll(final Collection c) {
if (N.isNullOrEmpty(c)) {
boolean result = size() > 0;
clear();
return result;
}
Set others = null;
for (T e : valueMap.keySet()) {
if (!c.contains(e)) {
if (others == null) {
others = N.newHashSet(valueMap.size());
}
others.add(e);
}
}
return N.isNullOrEmpty(others) ? false : removeAll(others, Integer.MAX_VALUE);
}
public Multiset copy() {
final Multiset copy = new Multiset<>(mapSupplier);
copy.addAll(this);
return copy;
}
public ImmutableSet elements() {
return ImmutableSet.of(valueMap.keySet());
}
public int size() {
return valueMap.size();
}
/**
* Checks if is empty.
*
* @return true, if is empty
*/
public boolean isEmpty() {
return valueMap.isEmpty();
}
/**
* Clear.
*/
public void clear() {
valueMap.clear();
}
@Override
public Iterator iterator() {
return valueMap.keySet().iterator();
}
public Iterator flatIterator() {
final Iterator> entryIter = valueMap.entrySet().iterator();
return new ObjIterator<>() {
private Map.Entry entry = null;
private T element = null;
private int count = 0;
private int cnt = 0;
@Override
public boolean hasNext() {
if (cnt >= count) {
while (cnt >= count && entryIter.hasNext()) {
entry = entryIter.next();
element = entry.getKey();
count = entry.getValue().value();
cnt = 0;
}
}
return cnt < count;
}
@Override
public T next() {
if (!hasNext()) {
throw new NoSuchElementException();
}
cnt++;
return element;
}
};
}
// public Set> entrySet() {
// return valueMap.entrySet();
// }
public Object[] toArray() {
return valueMap.keySet().toArray();
}
/**
*
* @param
* @param a
* @return
*/
public A[] toArray(final A[] a) {
return valueMap.keySet().toArray(a);
}
public Map toMap() {
final Map result = Maps.newOrderingMap(valueMap);
for (Map.Entry entry : valueMap.entrySet()) {
result.put(entry.getKey(), entry.getValue().value());
}
return result;
}
/**
*
* @param
* @param supplier
* @return
*/
public > M toMap(final IntFunction supplier) {
final M result = supplier.apply(size());
for (Map.Entry entry : valueMap.entrySet()) {
result.put(entry.getKey(), entry.getValue().value());
}
return result;
}
/**
* To map sorted by occurrences.
*
* @return
*/
@SuppressWarnings("rawtypes")
public Map toMapSortedByOccurrences() {
return toMapSortedBy((Comparator) cmpByCount);
}
/**
* To map sorted by occurrences.
*
* @param cmp
* @return
*/
public Map toMapSortedByOccurrences(final Comparator cmp) {
return toMapSortedBy((o1, o2) -> cmp.compare(o1.getValue().value(), o2.getValue().value()));
}
/**
* To map sorted by key.
*
* @param cmp
* @return
*/
public Map toMapSortedByKey(final Comparator cmp) {
return toMapSortedBy(Comparators. comparingByKey(cmp));
}
/**
* To map sorted by.
*
* @param cmp
* @return
*/
Map toMapSortedBy(final Comparator> cmp) {
if (N.isNullOrEmpty(valueMap)) {
return new LinkedHashMap<>();
}
final Map.Entry[] entries = valueMap.entrySet().toArray(new Map.Entry[size()]);
Arrays.sort(entries, cmp);
final Map sortedValues = N.newLinkedHashMap(size());
for (Map.Entry entry : entries) {
sortedValues.put(entry.getKey(), entry.getValue().value());
}
return sortedValues;
}
/**
* To immutable map.
*
* @return
*/
public ImmutableMap toImmutableMap() {
return ImmutableMap.of(toMap());
}
/**
* To immutable map.
*
* @param mapSupplier
* @return
*/
public ImmutableMap toImmutableMap(final IntFunction> mapSupplier) {
return ImmutableMap.of(toMap(mapSupplier));
}
// It won't work.
// public Multiset synchronizedd() {
// return new Multiset<>(Collections.synchronizedMap(valueMap));
// }
/**
*
* @return a list with all elements, each of them is repeated with the occurrences in this Multiset
*/
public List flatten() {
final long totalOccurrences = sumOfOccurrences();
if (totalOccurrences > Integer.MAX_VALUE) {
throw new RuntimeException("The total occurrences(" + totalOccurrences + ") is bigger than the max value of int.");
}
final Object[] a = new Object[(int) totalOccurrences];
int fromIndex = 0;
int toIndex = 0;
for (Map.Entry entry : valueMap.entrySet()) {
toIndex = fromIndex + entry.getValue().value();
Arrays.fill(a, fromIndex, toIndex, entry.getKey());
fromIndex = toIndex;
}
return N.asList((T[]) a);
}
/**
*
* @param
* @param filter
* @return
* @throws E the e
*/
public Multiset filter(Throwables.Predicate filter) throws E {
final Multiset result = new Multiset<>(mapSupplier.get());
for (Map.Entry entry : valueMap.entrySet()) {
if (filter.test(entry.getKey())) {
result.set(entry.getKey(), entry.getValue().intValue());
}
}
return result;
}
/**
*
* @param
* @param filter
* @return
* @throws E the e
*/
public Multiset filter(Throwables.BiPredicate filter) throws E {
final Multiset result = new Multiset<>(mapSupplier.get());
for (Map.Entry entry : valueMap.entrySet()) {
if (filter.test(entry.getKey(), entry.getValue().intValue())) {
result.set(entry.getKey(), entry.getValue().intValue());
}
}
return result;
}
/**
*
* @param
* @param action
* @throws E the e
*/
public void forEach(final Throwables.Consumer action) throws E {
N.checkArgNotNull(action);
for (T e : valueMap.keySet()) {
action.accept(e);
}
}
/**
*
* @param
* @param action
* @throws E the e
*/
public void forEach(final Throwables.ObjIntConsumer action) throws E {
N.checkArgNotNull(action);
for (Map.Entry entry : valueMap.entrySet()) {
action.accept(entry.getKey(), entry.getValue().value());
}
}
/**
* The implementation is equivalent to performing the following steps for this Multiset:
*
*
* final int oldValue = get(e);
*
* if (oldValue > 0) {
* return oldValue;
* }
*
* final int newValue = mappingFunction.apply(e);
*
* if (newValue > 0) {
* set(e, newValue);
* }
*
* return newValue;
*
*
* @param
* @param e
* @param mappingFunction
* @return
* @throws E the e
*/
public int computeIfAbsent(T e, Throwables.Function mappingFunction) throws E {
N.checkArgNotNull(mappingFunction);
final int oldValue = get(e);
if (oldValue > 0) {
return oldValue;
}
final int newValue = mappingFunction.apply(e);
if (newValue > 0) {
set(e, newValue);
}
return newValue;
}
/**
* The implementation is equivalent to performing the following steps for this Multiset:
*
*
* final int oldValue = get(e);
*
* if (oldValue == 0) {
* return oldValue;
* }
*
* final int newValue = remappingFunction.apply(e, oldValue);
*
* if (newValue > 0) {
* set(e, newValue);
* } else {
* remove(e);
* }
*
* return newValue;
*
*
* @param
* @param e
* @param remappingFunction
* @return
* @throws E the e
*/
public int computeIfPresent(T e, Throwables.BiFunction remappingFunction) throws E {
N.checkArgNotNull(remappingFunction);
final int oldValue = get(e);
if (oldValue == 0) {
return oldValue;
}
final int newValue = remappingFunction.apply(e, oldValue);
if (newValue > 0) {
set(e, newValue);
} else {
remove(e);
}
return newValue;
}
/**
* The implementation is equivalent to performing the following steps for this Multiset:
*
*
* final int oldValue = get(key);
* final int newValue = remappingFunction.apply(key, oldValue);
*
* if (newValue > 0) {
* set(key, newValue);
* } else {
* if (oldValue > 0) {
* remove(key);
* }
* }
*
* return newValue;
*
*
* @param
* @param key
* @param remappingFunction
* @return
* @throws E the e
*/
public int compute(T key, Throwables.BiFunction remappingFunction) throws E {
N.checkArgNotNull(remappingFunction);
final int oldValue = get(key);
final int newValue = remappingFunction.apply(key, oldValue);
if (newValue > 0) {
set(key, newValue);
} else {
if (oldValue > 0) {
remove(key);
}
}
return newValue;
}
/**
* The implementation is equivalent to performing the following steps for this Multiset:
*
*
* int oldValue = get(key);
* int newValue = (oldValue == 0) ? value : remappingFunction.apply(oldValue, value);
*
* if (newValue > 0) {
* set(key, newValue);
* } else {
* if (oldValue > 0) {
* remove(key);
* }
* }
*
* return newValue;
*
*
* @param
* @param key
* @param value
* @param remappingFunction
* @return
* @throws E the e
*/
public int merge(T key, int value, Throwables.BiFunction remappingFunction) throws E {
N.checkArgNotNull(remappingFunction);
N.checkArgNotNull(value);
int oldValue = get(key);
int newValue = (oldValue == 0) ? value : remappingFunction.apply(oldValue, value);
if (newValue > 0) {
set(key, newValue);
} else {
if (oldValue > 0) {
remove(key);
}
}
return newValue;
}
public Stream stream() {
return Stream.of(valueMap.keySet());
}
public Stream flatStream() {
return Stream.of(flatIterator());
}
private static final Function TO_INT = t -> t.value();
public EntryStream entryStream() {
return EntryStream.of(valueMap).mapValue(TO_INT);
}
/**
*
* @param
* @param
* @param func
* @return
* @throws E the e
*/
public R apply(Throwables.Function, R, E> func) throws E {
return func.apply(this);
}
/**
* Apply if not empty.
*
* @param
* @param
* @param func
* @return
* @throws E the e
*/
public Optional applyIfNotEmpty(Throwables.Function, R, E> func) throws E {
return isEmpty() ? Optional. empty() : Optional.ofNullable(func.apply(this));
}
/**
*
* @param
* @param action
* @throws E the e
*/
public void accept(Throwables.Consumer, E> action) throws E {
action.accept(this);
}
/**
* Accept if not empty.
*
* @param
* @param action
* @throws E the e
*/
public OrElse acceptIfNotEmpty(Throwables.Consumer, E> action) throws E {
return If.is(size() > 0).then(this, action);
}
@Override
public int hashCode() {
return valueMap.hashCode();
}
/**
*
* @param obj
* @return
*/
@Override
public boolean equals(final Object obj) {
return obj == this || (obj instanceof Multiset && valueMap.equals(((Multiset) obj).valueMap));
}
@Override
public String toString() {
return valueMap.toString();
}
/**
*
* @param occurrences
*/
private static void checkOccurrences(final int occurrences) {
if (occurrences < 0) {
throw new IllegalArgumentException("The specified 'occurrences' can not be negative");
}
}
}