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Java Simplified. Extensions and Useful Constructs for the Java Platform.
Codeprimate Elements (a.k.a. cp-elements) is a Java library and micro-framework used to simplify
the development of software applications written in Java. Elements packages several APIs into one
library in order to address various application concerns and aspects of software design and development
collectively and conveniently. Elements is a highly simple, yet robust and proven library built on
solid OO principles, software design patterns and best practices to effectively solve common
and reoccurring problems in software development.
/*
* Copyright 2016 Author or Authors.
*
* 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 org.cp.elements.lang;
import java.util.Optional;
import org.cp.elements.lang.annotation.NullSafe;
/**
* The {@link IdentifierSequence} interface defines a contract for implementing objects to generate
* unique identifiers (IDs) to uniquely identify some object or entity.
*
* @author John J. Blum
* @param is a {@link Comparable} class type of the identifying value.
* @see java.lang.Comparable
* @see java.lang.FunctionalInterface
* @see org.cp.elements.lang.Identifiable
* @since 1.0.0
*/
@FunctionalInterface
@SuppressWarnings("unused")
public interface IdentifierSequence> {
/**
* Generates the next unique ID in sequence.
*
* @return the next unique ID of class type T in the sequence.
*/
T nextId();
/**
* Sets the identifier of the given {@link Identifiable} object is not set.
*
* @param {@link Class} type of the {@link Identifiable} object.
* @param identifiable {@link Identifiable} object to identify (set the ID).
* @return the given {@link Identifiable} object.
* @see org.cp.elements.lang.Identifiable
*/
@NullSafe
default > S identify(S identifiable) {
return Optional.ofNullable(identifiable)
.filter(Identifiable::isNew)
.map(it -> it.identifiedBy(nextId()))
.orElse(identifiable);
}
}