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/*
 * JavaBean Tester (https://github.com/hazendaz/javabean-tester)
 *
 * Copyright 2012-2023 Hazendaz.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of The Apache Software License,
 * Version 2.0 which accompanies this distribution, and is available at
 * http://www.apache.org/licenses/LICENSE-2.0.txt
 *
 * Contributors:
 *     CodeBox (Rob Dawson).
 *     Hazendaz (Jeremy Landis).
 */
package com.codebox.instance;

import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;

import org.junit.jupiter.api.Assertions;

/**
 * The Constructor Instance.
 */
public final class ConstructorInstance {

    /**
     * Prevent Instantiation of a new constructor instance.
     */
    private ConstructorInstance() {
        // Prevent Instantiation
    }

    /**
     * New instance.
     *
     * @param constructor
     *            the instance
     *
     * @return the Object
     */
    public static Object newInstance(final Constructor constructor) {
        try {
            return constructor.newInstance();
        } catch (final InstantiationException | IllegalAccessException | InvocationTargetException e) {
            Assertions.fail(
                    String.format("An exception was thrown while testing the constructor (new instance) '%s': '%s'",
                            constructor.getName(), e.toString()));
        }
        return null;
    }

    /**
     * Constructor inaccessibility test.
     *
     * @param clazz
     *            the clazz
     */
    public static void inaccessible(final Class clazz) {
        final Constructor[] ctors = clazz.getDeclaredConstructors();
        Assertions.assertEquals(1, ctors.length, "Utility class should only have one constructor");
        final Constructor ctor = ctors[0];
        Assertions.assertFalse(ctor.canAccess(null), "Utility class constructor should be inaccessible");
        // Make accessible 'true' in order to test following assert.
        ctor.setAccessible(true);
        final Object object = ConstructorInstance.newInstance(ctor);
        Assertions.assertEquals(clazz, object == null ? "null" : object.getClass(),
                "You would expect the constructor to return the expected type");
        // Set accessible back to 'false'
        ctor.setAccessible(false);
    }
}