drv.Functions.drv Maven / Gradle / Ivy
Show all versions of fastutil Show documentation
/*
* Copyright (C) 2002-2017 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 PACKAGE;
import it.unimi.dsi.fastutil.Function;
/** 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 class FUNCTIONS {
private FUNCTIONS() {}
/** 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.
*/
public static class EmptyFunction KEY_VALUE_GENERIC extends ABSTRACT_FUNCTION KEY_VALUE_GENERIC implements java.io.Serializable, Cloneable {
private static final long serialVersionUID = -7046029254386353129L;
protected EmptyFunction() {}
@Override
public VALUE_GENERIC_TYPE GET_VALUE(final KEY_TYPE k) { return VALUE_NULL; }
@Override
public boolean containsKey(final KEY_TYPE k) { return false; }
@Override
public VALUE_GENERIC_TYPE defaultReturnValue() { return VALUE_NULL; }
@Override
public void defaultReturnValue(final VALUE_GENERIC_TYPE 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. */
SUPPRESS_WARNINGS_KEY_VALUE_RAWTYPES
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.
*/
public static class Singleton KEY_VALUE_GENERIC extends ABSTRACT_FUNCTION KEY_VALUE_GENERIC implements java.io.Serializable, Cloneable {
private static final long serialVersionUID = -7046029254386353129L;
protected final KEY_GENERIC_TYPE key;
protected final VALUE_GENERIC_TYPE value;
protected Singleton(final KEY_GENERIC_TYPE key, final VALUE_GENERIC_TYPE value) {
this.key = key;
this.value = value;
}
@Override
public boolean containsKey(final KEY_TYPE k) { return KEY_EQUALS(key, k); }
@Override
public VALUE_GENERIC_TYPE GET_VALUE(final KEY_TYPE k) { return KEY_EQUALS(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.
*
* @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 <key,value>.
*/
public static KEY_VALUE_GENERIC FUNCTION KEY_VALUE_GENERIC singleton(final KEY_GENERIC_TYPE key, VALUE_GENERIC_TYPE value) {
return new Singleton KEY_VALUE_GENERIC(key, value);
}
#if KEYS_PRIMITIVE || VALUES_PRIMITIVE
/** 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.
*
* @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 <key,value>.
*/
public static KEY_VALUE_GENERIC FUNCTION KEY_VALUE_GENERIC singleton(final KEY_GENERIC_CLASS key, final VALUE_GENERIC_CLASS value) {
return new Singleton KEY_VALUE_GENERIC(KEY_CLASS2TYPE(key), VALUE_CLASS2TYPE(value));
}
#endif
/** A synchronized wrapper class for functions. */
public static class SynchronizedFunction KEY_VALUE_GENERIC extends ABSTRACT_FUNCTION KEY_VALUE_GENERIC implements java.io.Serializable {
private static final long serialVersionUID = -7046029254386353129L;
protected final FUNCTION KEY_VALUE_GENERIC function;
protected final Object sync;
protected SynchronizedFunction(final FUNCTION KEY_VALUE_GENERIC f, final Object sync) {
if (f == null) throw new NullPointerException();
this.function = f;
this.sync = sync;
}
protected SynchronizedFunction(final FUNCTION KEY_VALUE_GENERIC f) {
if (f == null) throw new NullPointerException();
this.function = f;
this.sync = this;
}
@Override
public int size() { synchronized(sync) { return function.size(); } }
@Override
public VALUE_GENERIC_TYPE defaultReturnValue() { synchronized(sync) { return function.defaultReturnValue(); } }
@Override
public void defaultReturnValue(final VALUE_GENERIC_TYPE defRetValue) { synchronized(sync) { function.defaultReturnValue(defRetValue); } }
@Override
public boolean containsKey(final KEY_TYPE k) { synchronized(sync) { return function.containsKey(k); } }
#if KEYS_PRIMITIVE
@Deprecated
@Override
public boolean containsKey(final Object k) { synchronized(sync) { return function.containsKey(k); } }
#endif
@Override
public VALUE_GENERIC_TYPE put(final KEY_GENERIC_TYPE k, final VALUE_GENERIC_TYPE v) { synchronized(sync) { return function.put(k, v); } }
@Override
public VALUE_GENERIC_TYPE GET_VALUE(final KEY_TYPE k) { synchronized(sync) { return function.GET_VALUE(k); } }
@Override
public VALUE_GENERIC_TYPE REMOVE_VALUE(final KEY_TYPE k) { synchronized(sync) { return function.REMOVE_VALUE(k); } }
@Override
public void clear() { synchronized(sync) { function.clear(); } }
#if KEYS_PRIMITIVE || VALUES_PRIMITIVE
/** {@inheritDoc}
* @deprecated Please use the corresponding type-specific method instead. */
@Deprecated
@Override
public VALUE_GENERIC_CLASS put(final KEY_GENERIC_CLASS k, final VALUE_GENERIC_CLASS v) { synchronized(sync) { return function.put(k, v); } }
/** {@inheritDoc}
* @deprecated Please use the corresponding type-specific method instead. */
@Deprecated
@Override
public VALUE_GENERIC_CLASS get(final Object k) { synchronized(sync) { return function.get(k); } }
/** {@inheritDoc}
* @deprecated Please use the corresponding type-specific method instead. */
@Deprecated
@Override
public VALUE_GENERIC_CLASS remove(final Object k) { synchronized(sync) { return function.remove(k); } }
#endif
@Override
public int hashCode() { synchronized(sync) { return function.hashCode(); } }
@Override
public boolean equals(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.
*
* @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 KEY_VALUE_GENERIC FUNCTION KEY_VALUE_GENERIC synchronize(final FUNCTION KEY_VALUE_GENERIC f) { return new SynchronizedFunction KEY_VALUE_GENERIC(f); }
/** 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 KEY_VALUE_GENERIC FUNCTION KEY_VALUE_GENERIC synchronize(final FUNCTION KEY_VALUE_GENERIC f, final Object sync) { return new SynchronizedFunction KEY_VALUE_GENERIC(f, sync); }
/** An unmodifiable wrapper class for functions. */
public static class UnmodifiableFunction KEY_VALUE_GENERIC extends ABSTRACT_FUNCTION KEY_VALUE_GENERIC implements java.io.Serializable {
private static final long serialVersionUID = -7046029254386353129L;
protected final FUNCTION KEY_VALUE_GENERIC function;
protected UnmodifiableFunction(final FUNCTION KEY_VALUE_GENERIC f) {
if (f == null) throw new NullPointerException();
this.function = f;
}
@Override
public int size() { return function.size(); }
@Override
public VALUE_GENERIC_TYPE defaultReturnValue() { return function.defaultReturnValue(); }
@Override
public void defaultReturnValue(final VALUE_GENERIC_TYPE defRetValue) { throw new UnsupportedOperationException(); }
@Override
public boolean containsKey(final KEY_TYPE k) { return function.containsKey(k); }
@Override
public VALUE_GENERIC_TYPE put(final KEY_GENERIC_TYPE k, final VALUE_GENERIC_TYPE v) { throw new UnsupportedOperationException(); }
@Override
public VALUE_GENERIC_TYPE GET_VALUE(final KEY_TYPE k) { return function.GET_VALUE(k); }
@Override
public VALUE_GENERIC_TYPE REMOVE_VALUE(final KEY_TYPE k) { throw new UnsupportedOperationException(); }
@Override
public void clear() { throw new UnsupportedOperationException(); }
#if KEYS_PRIMITIVE || VALUES_PRIMITIVE
/** {@inheritDoc}
* @deprecated Please use the corresponding type-specific method instead. */
@Deprecated
@Override
public VALUE_GENERIC_CLASS put(final KEY_GENERIC_CLASS k, final VALUE_GENERIC_CLASS v) { throw new UnsupportedOperationException(); }
/** {@inheritDoc}
* @deprecated Please use the corresponding type-specific method instead. */
@Deprecated
@Override
public VALUE_GENERIC_CLASS get(final Object k) { return function.get(k); }
/** {@inheritDoc}
* @deprecated Please use the corresponding type-specific method instead. */
@Deprecated
@Override
public VALUE_GENERIC_CLASS remove(final Object k) { throw new UnsupportedOperationException(); }
#endif
@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.
*
* @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 KEY_VALUE_GENERIC FUNCTION KEY_VALUE_GENERIC unmodifiable(final FUNCTION KEY_VALUE_GENERIC f) { return new UnmodifiableFunction KEY_VALUE_GENERIC(f); }
}