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/*
* Copyright (C) 2002-2021 Sebastiano Vigna
*
* 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 it.unimi.dsi.fastutil.ints;
import static it.unimi.dsi.fastutil.Size64.sizeOf;
import it.unimi.dsi.fastutil.objects.ObjectIterator;
import it.unimi.dsi.fastutil.objects.ObjectSpliterator;
import it.unimi.dsi.fastutil.objects.ObjectSpliterators;
import it.unimi.dsi.fastutil.objects.AbstractObjectSet;
import java.util.Iterator;
import java.util.Map;
/**
* An abstract class providing basic methods for maps implementing a
* type-specific interface.
*
*
* Optional operations just throw an {@link UnsupportedOperationException}.
* Generic versions of accessors delegate to the corresponding type-specific
* counterparts following the interface rules (they take care of returning
* {@code null} on a missing key).
*
*
* As a further help, this class provides a {@link BasicEntry BasicEntry} inner
* class that implements a type-specific version of {@link java.util.Map.Entry};
* it is particularly useful for those classes that do not implement their own
* entries (e.g., most immutable maps).
*/
public abstract class AbstractInt2IntMap extends AbstractInt2IntFunction implements Int2IntMap, java.io.Serializable {
private static final long serialVersionUID = -4940583368468432370L;
protected AbstractInt2IntMap() {
}
/**
* {@inheritDoc}
*
* @implSpec This implementation does a linear search over the entry set,
* finding an entry that has the key specified.
*
* If you override {@link #keySet()}, you should probably override
* this method too to take advantage of the (presumably) faster
* {@linkplain java.util.Set#contains key membership test} your
* {@link #keySet()} provides.
*
* If you override this method but not {@link #keySet()}, then the
* returned key set will take advantage of this method.
*/
@Override
public boolean containsKey(final int k) {
final ObjectIterator i = int2IntEntrySet().iterator();
while (i.hasNext())
if (i.next().getIntKey() == k)
return true;
return false;
}
/**
* {@inheritDoc}
*
* @implSpec This implementation does a linear search over the entry set,
* finding an entry that has the value specified.
*
* If you override {@link #values()}, you should probably override
* this method too to take advantage of the (presumably) faster
* {@linkplain java.util.Collection#contains value membership test}
* your {@link #values()} provides.
*
* If you override this method but not {@link #values()}, then the
* returned values collection will take advantage of this method.
*/
@Override
public boolean containsValue(final int v) {
final ObjectIterator i = int2IntEntrySet().iterator();
while (i.hasNext())
if (i.next().getIntValue() == v)
return true;
return false;
}
@Override
public boolean isEmpty() {
return size() == 0;
}
/**
* {@inheritDoc}
*
* @implSpec This method just delegates to the interface default method, as the
* default method, but it is final, so it cannot be overridden.
*/
@Override
public final int mergeInt(final int key, final int value,
final it.unimi.dsi.fastutil.ints.IntBinaryOperator remappingFunction) {
return mergeInt(key, value, (java.util.function.IntBinaryOperator) remappingFunction);
}
/**
* This class provides a basic but complete type-specific entry class for all
* those maps implementations that do not have entries on their own (e.g., most
* immutable maps).
*
*
* This class does not implement {@link java.util.Map.Entry#setValue(Object)
* setValue()}, as the modification would not be reflected in the base map.
*/
public static class BasicEntry implements Int2IntMap.Entry {
protected int key;
protected int value;
public BasicEntry() {
}
public BasicEntry(final Integer key, final Integer value) {
this.key = (key).intValue();
this.value = (value).intValue();
}
public BasicEntry(final int key, final int value) {
this.key = key;
this.value = value;
}
@Override
public int getIntKey() {
return key;
}
@Override
public int getIntValue() {
return value;
}
@Override
public int setValue(final int value) {
throw new UnsupportedOperationException();
}
@Override
public boolean equals(final Object o) {
if (!(o instanceof Map.Entry))
return false;
if (o instanceof Int2IntMap.Entry) {
final Int2IntMap.Entry e = (Int2IntMap.Entry) o;
return ((key) == (e.getIntKey())) && ((value) == (e.getIntValue()));
}
final Map.Entry e = (Map.Entry) o;
final Object key = e.getKey();
if (key == null || !(key instanceof Integer))
return false;
final Object value = e.getValue();
if (value == null || !(value instanceof Integer))
return false;
return ((this.key) == (((Integer) (key)).intValue())) && ((this.value) == (((Integer) (value)).intValue()));
}
@Override
public int hashCode() {
return (key) ^ (value);
}
@Override
public String toString() {
return key + "->" + value;
}
}
/**
* This class provides a basic implementation for an Entry set which forwards
* some queries to the map.
*/
public abstract static class BasicEntrySet extends AbstractObjectSet {
protected final Int2IntMap map;
public BasicEntrySet(final Int2IntMap map) {
this.map = map;
}
@Override
public boolean contains(final Object o) {
if (!(o instanceof Map.Entry))
return false;
if (o instanceof Int2IntMap.Entry) {
final Int2IntMap.Entry e = (Int2IntMap.Entry) o;
final int k = e.getIntKey();
return map.containsKey(k) && ((map.get(k)) == (e.getIntValue()));
}
final Map.Entry e = (Map.Entry) o;
final Object key = e.getKey();
if (key == null || !(key instanceof Integer))
return false;
final int k = ((Integer) (key)).intValue();
final Object value = e.getValue();
if (value == null || !(value instanceof Integer))
return false;
return map.containsKey(k) && ((map.get(k)) == (((Integer) (value)).intValue()));
}
@Override
public boolean remove(final Object o) {
if (!(o instanceof Map.Entry))
return false;
if (o instanceof Int2IntMap.Entry) {
final Int2IntMap.Entry e = (Int2IntMap.Entry) o;
return map.remove(e.getIntKey(), e.getIntValue());
}
Map.Entry e = (Map.Entry) o;
final Object key = e.getKey();
if (key == null || !(key instanceof Integer))
return false;
final int k = ((Integer) (key)).intValue();
final Object value = e.getValue();
if (value == null || !(value instanceof Integer))
return false;
final int v = ((Integer) (value)).intValue();
return map.remove(k, v);
}
@Override
public int size() {
return map.size();
}
@Override
public ObjectSpliterator spliterator() {
return ObjectSpliterators.asSpliterator(iterator(), sizeOf(map),
ObjectSpliterators.SET_SPLITERATOR_CHARACTERISTICS);
}
}
/**
* Returns a type-specific-set view of the keys of this map.
*
*
* The view is backed by the set returned by {@link Map#entrySet()}. Note that
* no attempt is made at caching the result of this method, as this
* would require adding some attributes that lightweight implementations would
* not need. Subclasses may easily override this policy by calling this method
* and caching the result, but implementors are encouraged to write more
* efficient ad-hoc implementations.
*
* @return a set view of the keys of this map; it may be safely cast to a
* type-specific interface.
*/
@Override
public IntSet keySet() {
return new AbstractIntSet() {
@Override
public boolean contains(final int k) {
return containsKey(k);
}
@Override
public int size() {
return AbstractInt2IntMap.this.size();
}
@Override
public void clear() {
AbstractInt2IntMap.this.clear();
}
@Override
public IntIterator iterator() {
return new IntIterator() {
private final ObjectIterator i = Int2IntMaps
.fastIterator(AbstractInt2IntMap.this);
@Override
public int nextInt() {
return i.next().getIntKey();
}
@Override
public boolean hasNext() {
return i.hasNext();
}
@Override
public void remove() {
i.remove();
}
@Override
public void forEachRemaining(final java.util.function.IntConsumer action) {
i.forEachRemaining(entry -> action.accept(entry.getIntKey()));
}
};
}
@Override
public IntSpliterator spliterator() {
return IntSpliterators.asSpliterator(iterator(), sizeOf(AbstractInt2IntMap.this),
IntSpliterators.SET_SPLITERATOR_CHARACTERISTICS);
}
};
}
/**
* Returns a type-specific-set view of the values of this map.
*
*
* The view is backed by the set returned by {@link Map#entrySet()}. Note that
* no attempt is made at caching the result of this method, as this
* would require adding some attributes that lightweight implementations would
* not need. Subclasses may easily override this policy by calling this method
* and caching the result, but implementors are encouraged to write more
* efficient ad-hoc implementations.
*
* @return a set view of the values of this map; it may be safely cast to a
* type-specific interface.
*/
@Override
public IntCollection values() {
return new AbstractIntCollection() {
@Override
public boolean contains(final int k) {
return containsValue(k);
}
@Override
public int size() {
return AbstractInt2IntMap.this.size();
}
@Override
public void clear() {
AbstractInt2IntMap.this.clear();
}
@Override
public IntIterator iterator() {
return new IntIterator() {
private final ObjectIterator i = Int2IntMaps
.fastIterator(AbstractInt2IntMap.this);
@Override
public int nextInt() {
return i.next().getIntValue();
}
@Override
public boolean hasNext() {
return i.hasNext();
}
@Override
public void remove() {
i.remove();
}
@Override
public void forEachRemaining(final java.util.function.IntConsumer action) {
i.forEachRemaining(entry -> action.accept(entry.getIntValue()));
}
};
}
@Override
public IntSpliterator spliterator() {
return IntSpliterators.asSpliterator(iterator(), sizeOf(AbstractInt2IntMap.this),
IntSpliterators.COLLECTION_SPLITERATOR_CHARACTERISTICS);
}
};
}
/** {@inheritDoc} */
@SuppressWarnings({"unchecked", "deprecation"})
@Override
public void putAll(final Map m) {
if (m instanceof Int2IntMap) {
ObjectIterator i = Int2IntMaps.fastIterator((Int2IntMap) m);
while (i.hasNext()) {
final Int2IntMap.Entry e = i.next();
put(e.getIntKey(), e.getIntValue());
}
} else {
int n = m.size();
final Iterator> i = m.entrySet().iterator();
Map.Entry e;
while (n-- != 0) {
e = i.next();
put(e.getKey(), e.getValue());
}
}
}
/**
* Returns a hash code for this map.
*
* The hash code of a map is computed by summing the hash codes of its entries.
*
* @return a hash code for this map.
*/
@Override
public int hashCode() {
int h = 0, n = size();
final ObjectIterator i = Int2IntMaps.fastIterator(this);
while (n-- != 0)
h += i.next().hashCode();
return h;
}
@Override
public boolean equals(Object o) {
if (o == this)
return true;
if (!(o instanceof Map))
return false;
final Map m = (Map) o;
if (m.size() != size())
return false;
return int2IntEntrySet().containsAll(m.entrySet());
}
@Override
public String toString() {
final StringBuilder s = new StringBuilder();
final ObjectIterator i = Int2IntMaps.fastIterator(this);
int n = size();
Int2IntMap.Entry e;
boolean first = true;
s.append("{");
while (n-- != 0) {
if (first)
first = false;
else
s.append(", ");
e = i.next();
s.append(String.valueOf(e.getIntKey()));
s.append("=>");
s.append(String.valueOf(e.getIntValue()));
}
s.append("}");
return s.toString();
}
}