/*
* Copyright (C) 2002-2019 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.chars;
import it.unimi.dsi.fastutil.Function;
A class providing static methods and objects that do useful things with
type-specific functions.
See Also: - Function
- Collections
/**
* A class providing static methods and objects that do useful things with
* type-specific functions.
*
* @see it.unimi.dsi.fastutil.Function
* @see java.util.Collections
*/
public final class Char2CharFunctions {
private Char2CharFunctions() {
}
An immutable class representing an empty type-specific function.
This class may be useful to implement your own in case you subclass a
type-specific function.
/**
* An immutable class representing an empty type-specific function.
*
* <p>
* This class may be useful to implement your own in case you subclass a
* type-specific function.
*/
public static class EmptyFunction extends AbstractChar2CharFunction implements java.io.Serializable, Cloneable {
private static final long serialVersionUID = -7046029254386353129L;
protected EmptyFunction() {
}
@Override
public char get(final char k) {
return ((char) 0);
}
@Override
public boolean containsKey(final char k) {
return false;
}
@Override
public char defaultReturnValue() {
return ((char) 0);
}
@Override
public void defaultReturnValue(final char defRetValue) {
throw new UnsupportedOperationException();
}
@Override
public int size() {
return 0;
}
@Override
public void clear() {
}
@Override
public Object clone() {
return EMPTY_FUNCTION;
}
@Override
public int hashCode() {
return 0;
}
@Override
public boolean equals(final Object o) {
if (!(o instanceof Function))
return false;
return ((Function<?, ?>) o).size() == 0;
}
@Override
public String toString() {
return "{}";
}
private Object readResolve() {
return EMPTY_FUNCTION;
}
}
An empty type-specific function (immutable). It is serializable and
cloneable.
/**
* An empty type-specific function (immutable). It is serializable and
* cloneable.
*/
public static final EmptyFunction EMPTY_FUNCTION = new EmptyFunction();
An immutable class representing a type-specific singleton function. Note that
the default return value is still settable.
Note that albeit the function is immutable, its default return value may be
changed.
This class may be useful to implement your own in case you subclass a
type-specific function.
/**
* An immutable class representing a type-specific singleton function. Note that
* the default return value is still settable.
*
* <p>
* Note that albeit the function is immutable, its default return value may be
* changed.
*
* <p>
* This class may be useful to implement your own in case you subclass a
* type-specific function.
*/
public static class Singleton extends AbstractChar2CharFunction implements java.io.Serializable, Cloneable {
private static final long serialVersionUID = -7046029254386353129L;
protected final char key;
protected final char value;
protected Singleton(final char key, final char value) {
this.key = key;
this.value = value;
}
@Override
public boolean containsKey(final char k) {
return ((key) == (k));
}
@Override
public char get(final char k) {
return ((key) == (k)) ? value : defRetValue;
}
@Override
public int size() {
return 1;
}
@Override
public Object clone() {
return this;
}
}
Returns a type-specific immutable function containing only the specified
pair. The returned function is serializable and cloneable.
Note that albeit the returned function is immutable, its default return value
may be changed.
Params: - key –
the only key of the returned function.
- value –
the only value of the returned function.
Returns: a type-specific immutable function containing just the pair <key,value>
.
/**
* Returns a type-specific immutable function containing only the specified
* pair. The returned function is serializable and cloneable.
*
* <p>
* Note that albeit the returned function is immutable, its default return value
* may be changed.
*
* @param key
* the only key of the returned function.
* @param value
* the only value of the returned function.
* @return a type-specific immutable function containing just the pair
* {@code <key,value>}.
*/
public static Char2CharFunction singleton(final char key, char value) {
return new Singleton(key, value);
}
Returns a type-specific immutable function containing only the specified
pair. The returned function is serializable and cloneable.
Note that albeit the returned function is immutable, its default return value
may be changed.
Params: - key –
the only key of the returned function.
- value –
the only value of the returned function.
Returns: a type-specific immutable function containing just the pair <key,value>
.
/**
* Returns a type-specific immutable function containing only the specified
* pair. The returned function is serializable and cloneable.
*
* <p>
* Note that albeit the returned function is immutable, its default return value
* may be changed.
*
* @param key
* the only key of the returned function.
* @param value
* the only value of the returned function.
* @return a type-specific immutable function containing just the pair
* {@code <key,value>}.
*/
public static Char2CharFunction singleton(final Character key, final Character value) {
return new Singleton((key).charValue(), (value).charValue());
}
A synchronized wrapper class for functions. /** A synchronized wrapper class for functions. */
public static class SynchronizedFunction implements Char2CharFunction, java.io.Serializable {
private static final long serialVersionUID = -7046029254386353129L;
protected final Char2CharFunction function;
protected final Object sync;
protected SynchronizedFunction(final Char2CharFunction f, final Object sync) {
if (f == null)
throw new NullPointerException();
this.function = f;
this.sync = sync;
}
protected SynchronizedFunction(final Char2CharFunction f) {
if (f == null)
throw new NullPointerException();
this.function = f;
this.sync = this;
}
{@inheritDoc}
Deprecated: Please use the corresponding type-specific method instead.
/**
* {@inheritDoc}
*
* @deprecated Please use the corresponding type-specific method instead.
*/
@Deprecated
@Override
public int applyAsInt(int operand) {
synchronized (sync) {
return function.applyAsInt(operand);
}
}
{@inheritDoc}
Deprecated: Please use the corresponding type-specific method instead.
/**
* {@inheritDoc}
*
* @deprecated Please use the corresponding type-specific method instead.
*/
@Deprecated
@Override
public Character apply(final Character key) {
synchronized (sync) {
return function.apply(key);
}
}
@Override
public int size() {
synchronized (sync) {
return function.size();
}
}
@Override
public char defaultReturnValue() {
synchronized (sync) {
return function.defaultReturnValue();
}
}
@Override
public void defaultReturnValue(final char defRetValue) {
synchronized (sync) {
function.defaultReturnValue(defRetValue);
}
}
@Override
public boolean containsKey(final char k) {
synchronized (sync) {
return function.containsKey(k);
}
}
@Deprecated
@Override
public boolean containsKey(final Object k) {
synchronized (sync) {
return function.containsKey(k);
}
}
@Override
public char put(final char k, final char v) {
synchronized (sync) {
return function.put(k, v);
}
}
@Override
public char get(final char k) {
synchronized (sync) {
return function.get(k);
}
}
@Override
public char remove(final char k) {
synchronized (sync) {
return function.remove(k);
}
}
@Override
public void clear() {
synchronized (sync) {
function.clear();
}
}
{@inheritDoc}
Deprecated: Please use the corresponding type-specific method instead.
/**
* {@inheritDoc}
*
* @deprecated Please use the corresponding type-specific method instead.
*/
@Deprecated
@Override
public Character put(final Character k, final Character v) {
synchronized (sync) {
return function.put(k, v);
}
}
{@inheritDoc}
Deprecated: Please use the corresponding type-specific method instead.
/**
* {@inheritDoc}
*
* @deprecated Please use the corresponding type-specific method instead.
*/
@Deprecated
@Override
public Character get(final Object k) {
synchronized (sync) {
return function.get(k);
}
}
{@inheritDoc}
Deprecated: Please use the corresponding type-specific method instead.
/**
* {@inheritDoc}
*
* @deprecated Please use the corresponding type-specific method instead.
*/
@Deprecated
@Override
public Character remove(final Object k) {
synchronized (sync) {
return function.remove(k);
}
}
@Override
public int hashCode() {
synchronized (sync) {
return function.hashCode();
}
}
@Override
public boolean equals(final Object o) {
if (o == this)
return true;
synchronized (sync) {
return function.equals(o);
}
}
@Override
public String toString() {
synchronized (sync) {
return function.toString();
}
}
private void writeObject(java.io.ObjectOutputStream s) throws java.io.IOException {
synchronized (sync) {
s.defaultWriteObject();
}
}
}
Returns a synchronized type-specific function backed by the given
type-specific function.
Params: - f –
the function to be wrapped in a synchronized function.
See Also: Returns: a synchronized view of the specified function.
/**
* Returns a synchronized type-specific function backed by the given
* type-specific function.
*
* @param f
* the function to be wrapped in a synchronized function.
* @return a synchronized view of the specified function.
* @see java.util.Collections#synchronizedMap(java.util.Map)
*/
public static Char2CharFunction synchronize(final Char2CharFunction f) {
return new SynchronizedFunction(f);
}
Returns a synchronized type-specific function backed by the given
type-specific function, using an assigned object to synchronize.
Params: - f –
the function to be wrapped in a synchronized function.
- sync –
an object that will be used to synchronize the access to the
function.
See Also: Returns: a synchronized view of the specified function.
/**
* Returns a synchronized type-specific function backed by the given
* type-specific function, using an assigned object to synchronize.
*
* @param f
* the function to be wrapped in a synchronized function.
* @param sync
* an object that will be used to synchronize the access to the
* function.
* @return a synchronized view of the specified function.
* @see java.util.Collections#synchronizedMap(java.util.Map)
*/
public static Char2CharFunction synchronize(final Char2CharFunction f, final Object sync) {
return new SynchronizedFunction(f, sync);
}
An unmodifiable wrapper class for functions. /** An unmodifiable wrapper class for functions. */
public static class UnmodifiableFunction extends AbstractChar2CharFunction implements java.io.Serializable {
private static final long serialVersionUID = -7046029254386353129L;
protected final Char2CharFunction function;
protected UnmodifiableFunction(final Char2CharFunction f) {
if (f == null)
throw new NullPointerException();
this.function = f;
}
@Override
public int size() {
return function.size();
}
@Override
public char defaultReturnValue() {
return function.defaultReturnValue();
}
@Override
public void defaultReturnValue(final char defRetValue) {
throw new UnsupportedOperationException();
}
@Override
public boolean containsKey(final char k) {
return function.containsKey(k);
}
@Override
public char put(final char k, final char v) {
throw new UnsupportedOperationException();
}
@Override
public char get(final char k) {
return function.get(k);
}
@Override
public char remove(final char k) {
throw new UnsupportedOperationException();
}
@Override
public void clear() {
throw new UnsupportedOperationException();
}
{@inheritDoc}
Deprecated: Please use the corresponding type-specific method instead.
/**
* {@inheritDoc}
*
* @deprecated Please use the corresponding type-specific method instead.
*/
@Deprecated
@Override
public Character put(final Character k, final Character v) {
throw new UnsupportedOperationException();
}
{@inheritDoc}
Deprecated: Please use the corresponding type-specific method instead.
/**
* {@inheritDoc}
*
* @deprecated Please use the corresponding type-specific method instead.
*/
@Deprecated
@Override
public Character get(final Object k) {
return function.get(k);
}
{@inheritDoc}
Deprecated: Please use the corresponding type-specific method instead.
/**
* {@inheritDoc}
*
* @deprecated Please use the corresponding type-specific method instead.
*/
@Deprecated
@Override
public Character remove(final Object k) {
throw new UnsupportedOperationException();
}
@Override
public int hashCode() {
return function.hashCode();
}
@Override
public boolean equals(Object o) {
return o == this || function.equals(o);
}
@Override
public String toString() {
return function.toString();
}
}
Returns an unmodifiable type-specific function backed by the given
type-specific function.
Params: - f –
the function to be wrapped in an unmodifiable function.
See Also: Returns: an unmodifiable view of the specified function.
/**
* Returns an unmodifiable type-specific function backed by the given
* type-specific function.
*
* @param f
* the function to be wrapped in an unmodifiable function.
* @return an unmodifiable view of the specified function.
* @see java.util.Collections#unmodifiableMap(java.util.Map)
*/
public static Char2CharFunction unmodifiable(final Char2CharFunction f) {
return new UnmodifiableFunction(f);
}
An adapter for mapping generic total functions to partial primitive
functions.
/**
* An adapter for mapping generic total functions to partial primitive
* functions.
*/
public static class PrimitiveFunction implements Char2CharFunction {
protected final java.util.function.Function<? super Character, ? extends Character> function;
protected PrimitiveFunction(java.util.function.Function<? super Character, ? extends Character> function) {
this.function = function;
}
@Override
public boolean containsKey(char key) {
return function.apply(Character.valueOf(key)) != null;
}
@Deprecated
@Override
public boolean containsKey(Object key) {
if (key == null)
return false;
return function.apply((Character) (key)) != null;
}
@Override
public char get(char key) {
Character v = function.apply(Character.valueOf(key));
if (v == null)
return defaultReturnValue();
return (v).charValue();
}
@Deprecated
@Override
public Character get(Object key) {
if (key == null)
return null;
return function.apply((Character) key);
}
@Deprecated
@Override
public Character put(final Character key, final Character value) {
throw new UnsupportedOperationException();
}
}
Returns a (partial) type-specific function based on the given total generic
function.
The returned function contains all keys which are not mapped to null
. If the function already is a primitive function, it is returned without changes.
Warning: If the given function is a “widened” primitive function (e.g. an Int2IntFunction
given to Short2ShortFunctions
), it still is wrapped into a proxy, decreasing performance.
Params: - f –
the function to be converted to a type-specific function.
Throws: - NullPointerException – if
f
is null.
See Also: Returns: a primitive view of the specified function. Since: 8.1.0
/**
* Returns a (partial) type-specific function based on the given total generic
* function.
* <p>
* The returned function contains all keys which are not mapped to {@code null}.
* If the function already is a primitive function, it is returned without
* changes.
* <p>
* <strong>Warning</strong>: If the given function is a “widened”
* primitive function (e.g. an {@code Int2IntFunction} given to
* {@code Short2ShortFunctions}), it still is wrapped into a proxy, decreasing
* performance.
*
* @param f
* the function to be converted to a type-specific function.
* @return a primitive view of the specified function.
* @throws NullPointerException
* if {@code f} is null.
* @see PrimitiveFunction
* @since 8.1.0
*/
public static Char2CharFunction primitive(
final java.util.function.Function<? super Character, ? extends Character> f) {
java.util.Objects.requireNonNull(f);
if (f instanceof Char2CharFunction)
return (Char2CharFunction) f;
if (f instanceof java.util.function.IntUnaryOperator)
return key -> it.unimi.dsi.fastutil.SafeMath
.safeIntToChar(((java.util.function.IntUnaryOperator) f).applyAsInt(key));
return new PrimitiveFunction(f);
}
}