com.foreach.common.spring.enums.CodeLookup Maven / Gradle / Ivy
/*
* Copyright 2014 the original 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 com.foreach.common.spring.enums;
/**
* CodeLookup is an interface to facilitate finding elements in small sets of enumerated Objects,
* usually a java Enum.
*
* getCode returns a value that can be used to retrieve the Object.
* The actual lookup is not part of this interface,
* because it will be in most cases implemented by either a static method or a service.
*
* In order for this interface to be of use, getCode must return unique codes across all instances
* of a given implementation, so when
*
* class Foo implements CodeLookup<Integer>
*
* then if
*
* foo1.getCode().equals(foo2.getCode())
*
* is true, so should.
*
* foo1.equals(foo2)
*
*
* Typical usecases are web requests or database persistence.
*/
public interface CodeLookup
{
/**
* Returns the unique code of type <S> for this instance.
*/
S getCode();
}