org.meanbean.factories.equivalent.EquivalentEnumFactory Maven / Gradle / Ivy
/*-
*
* meanbean
*
* Copyright (C) 2010 - 2020 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 org.meanbean.factories.equivalent;
import org.meanbean.lang.EquivalentFactory;
import org.meanbean.util.ValidationHelper;
/**
* Concrete Factory that always creates the same Enum constant of the specified Enum type.
*
* @author Graham Williamson
*/
public class EquivalentEnumFactory implements EquivalentFactory> {
/** Enum constants of the specified Enum type. */
private final Enum[] enumConstants;
/**
* Construct a new Factory.
*
* @param enumClass
* The type of Enum to create Enum constants of.
*
* @throws IllegalArgumentException
* If enumClass is deemed illegal. For example, if it is null.
*/
public EquivalentEnumFactory(Class enumClass) throws IllegalArgumentException {
ValidationHelper.ensureExists("enumClass", "construct EnumFactory", enumClass);
if (!enumClass.isEnum()) {
throw new IllegalArgumentException("Cannot create EnumFactory for non-Enum class.");
}
this.enumConstants = (Enum[]) enumClass.getEnumConstants();
}
/**
* Create an Enum constant of the specified Enum type.
*
* @return An Enum constant of the specified Enum type.
*/
@Override
public Enum create() {
return enumConstants[0];
}
}