it.unimi.dsi.fastutil.objects.AbstractObject2ObjectFunction Maven / Gradle / Ivy
/*
* 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 it.unimi.dsi.fastutil.objects;
/** An abstract class providing basic methods for functions 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).
*
*
This class handles directly a default return
* value (including {@linkplain #defaultReturnValue() methods to access
* it}). Instances of classes inheriting from this class have just to return
* defRetValue to denote lack of a key in type-specific methods. The value
* is serialized.
*
*
Implementing subclasses have just to provide type-specific get(),
* type-specific containsKey(), and size() methods.
*
*/
public abstract class AbstractObject2ObjectFunction implements Object2ObjectFunction , java.io.Serializable {
private static final long serialVersionUID = -4940583368468432370L;
protected AbstractObject2ObjectFunction() {}
/**
* The default return value for get(), put() and
* remove().
*/
protected V defRetValue;
@Override
public void defaultReturnValue(final V rv) {
defRetValue = rv;
}
@Override
public V defaultReturnValue() {
return defRetValue;
}
/** {@inheritDoc}
*
* This implementation always throws an {@link UnsupportedOperationException}.
*/
public V put(K key, V value) {
throw new UnsupportedOperationException();
}
/** {@inheritDoc}
*
*
This implementation always throws an {@link UnsupportedOperationException}.
*/
public V remove(Object key) {
throw new UnsupportedOperationException();
}
/** {@inheritDoc}
*
*
This implementation always throws an {@link UnsupportedOperationException}.
*/
public void clear() {
throw new UnsupportedOperationException();
}
}