it.unimi.dsi.fastutil.bytes.AbstractByte2CharMap Maven / Gradle / Ivy
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/*
* Copyright (C) 2002-2022 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.bytes;
import static it.unimi.dsi.fastutil.Size64.sizeOf;
import it.unimi.dsi.fastutil.chars.CharCollection;
import it.unimi.dsi.fastutil.chars.AbstractCharCollection;
import it.unimi.dsi.fastutil.chars.CharIterator;
import it.unimi.dsi.fastutil.chars.CharSpliterator;
import it.unimi.dsi.fastutil.chars.CharSpliterators;
import it.unimi.dsi.fastutil.chars.CharConsumer;
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 AbstractByte2CharMap extends AbstractByte2CharFunction implements Byte2CharMap, java.io.Serializable {
private static final long serialVersionUID = -4940583368468432370L;
protected AbstractByte2CharMap() {
}
/**
* {@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 byte k) {
final ObjectIterator i = byte2CharEntrySet().iterator();
while (i.hasNext()) if (i.next().getByteKey() == 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 char v) {
final ObjectIterator i = byte2CharEntrySet().iterator();
while (i.hasNext()) if (i.next().getCharValue() == v) return true;
return false;
}
@Override
public boolean isEmpty() {
return size() == 0;
}
/**
* 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 Byte2CharMap.Entry {
protected byte key;
protected char value;
public BasicEntry() {
}
public BasicEntry(final Byte key, final Character value) {
this.key = (key).byteValue();
this.value = (value).charValue();
}
public BasicEntry(final byte key, final char value) {
this.key = key;
this.value = value;
}
@Override
public byte getByteKey() {
return key;
}
@Override
public char getCharValue() {
return value;
}
@Override
public char setValue(final char value) {
throw new UnsupportedOperationException();
}
@Override
public boolean equals(final Object o) {
if (!(o instanceof Map.Entry)) return false;
if (o instanceof Byte2CharMap.Entry) {
final Byte2CharMap.Entry e = (Byte2CharMap.Entry)o;
return ((key) == (e.getByteKey())) && ((value) == (e.getCharValue()));
}
final Map.Entry e = (Map.Entry)o;
final Object key = e.getKey();
if (key == null || !(key instanceof Byte)) return false;
final Object value = e.getValue();
if (value == null || !(value instanceof Character)) return false;
return ((this.key) == (((Byte)(key)).byteValue())) && ((this.value) == (((Character)(value)).charValue()));
}
@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 Byte2CharMap map;
public BasicEntrySet(final Byte2CharMap map) {
this.map = map;
}
@Override
public boolean contains(final Object o) {
if (!(o instanceof Map.Entry)) return false;
if (o instanceof Byte2CharMap.Entry) {
final Byte2CharMap.Entry e = (Byte2CharMap.Entry)o;
final byte k = e.getByteKey();
return map.containsKey(k) && ((map.get(k)) == (e.getCharValue()));
}
final Map.Entry e = (Map.Entry)o;
final Object key = e.getKey();
if (key == null || !(key instanceof Byte)) return false;
final byte k = ((Byte)(key)).byteValue();
final Object value = e.getValue();
if (value == null || !(value instanceof Character)) return false;
return map.containsKey(k) && ((map.get(k)) == (((Character)(value)).charValue()));
}
@Override
public boolean remove(final Object o) {
if (!(o instanceof Map.Entry)) return false;
if (o instanceof Byte2CharMap.Entry) {
final Byte2CharMap.Entry e = (Byte2CharMap.Entry)o;
return map.remove(e.getByteKey(), e.getCharValue());
}
Map.Entry e = (Map.Entry)o;
final Object key = e.getKey();
if (key == null || !(key instanceof Byte)) return false;
final byte k = ((Byte)(key)).byteValue();
final Object value = e.getValue();
if (value == null || !(value instanceof Character)) return false;
final char v = ((Character)(value)).charValue();
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 ByteSet keySet() {
return new AbstractByteSet() {
@Override
public boolean contains(final byte k) {
return containsKey(k);
}
@Override
public int size() {
return AbstractByte2CharMap.this.size();
}
@Override
public void clear() {
AbstractByte2CharMap.this.clear();
}
@Override
public ByteIterator iterator() {
return new ByteIterator() {
private final ObjectIterator i = Byte2CharMaps.fastIterator(AbstractByte2CharMap.this);
@Override
public byte nextByte() {
return i.next().getByteKey();
}
@Override
public boolean hasNext() {
return i.hasNext();
}
@Override
public void remove() {
i.remove();
}
@Override
public void forEachRemaining(final ByteConsumer action) {
i.forEachRemaining(entry -> action.accept(entry.getByteKey()));
}
};
}
@Override
public ByteSpliterator spliterator() {
return ByteSpliterators.asSpliterator(iterator(), sizeOf(AbstractByte2CharMap.this), ByteSpliterators.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 CharCollection values() {
return new AbstractCharCollection() {
@Override
public boolean contains(final char k) {
return containsValue(k);
}
@Override
public int size() {
return AbstractByte2CharMap.this.size();
}
@Override
public void clear() {
AbstractByte2CharMap.this.clear();
}
@Override
public CharIterator iterator() {
return new CharIterator() {
private final ObjectIterator i = Byte2CharMaps.fastIterator(AbstractByte2CharMap.this);
@Override
public char nextChar() {
return i.next().getCharValue();
}
@Override
public boolean hasNext() {
return i.hasNext();
}
@Override
public void remove() {
i.remove();
}
@Override
public void forEachRemaining(final CharConsumer action) {
i.forEachRemaining(entry -> action.accept(entry.getCharValue()));
}
};
}
@Override
public CharSpliterator spliterator() {
return CharSpliterators.asSpliterator(iterator(), sizeOf(AbstractByte2CharMap.this), CharSpliterators.COLLECTION_SPLITERATOR_CHARACTERISTICS);
}
};
}
/** {@inheritDoc} */
@SuppressWarnings({ "unchecked", "deprecation" })
@Override
public void putAll(final Map m) {
if (m instanceof Byte2CharMap) {
ObjectIterator i = Byte2CharMaps.fastIterator((Byte2CharMap)m);
while (i.hasNext()) {
final Byte2CharMap.Entry e = i.next();
put(e.getByteKey(), e.getCharValue());
}
} 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 = Byte2CharMaps.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 byte2CharEntrySet().containsAll(m.entrySet());
}
@Override
public String toString() {
final StringBuilder s = new StringBuilder();
final ObjectIterator i = Byte2CharMaps.fastIterator(this);
int n = size();
Byte2CharMap.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.getByteKey()));
s.append("=>");
s.append(String.valueOf(e.getCharValue()));
}
s.append("}");
return s.toString();
}
}