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/*
 * MIT License
 *
 * Copyright (c) 2020 Udo Borkowski, ([email protected])
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

package org.abego.commons.lang;

import org.abego.commons.lang.exception.MustNotInstantiateException;
import org.eclipse.jdt.annotation.NonNull;
import org.eclipse.jdt.annotation.Nullable;

import java.text.MessageFormat;

import static org.abego.commons.lang.ClassUtil.classNameOrNull;

public final class ObjectUtil {

    ObjectUtil() {
        throw new MustNotInstantiateException();
    }

    /**
     * Do nothing, ignore the argument.
     *
     * The method is typically used in test code to avoid
     * "Result of 'foo()' is ignored" warnings.
     *
     * Usage Example:
     *      * assertThrows(Exception.class, () -> ignore(firstChar("")));
     * 
     */
    @SuppressWarnings("EmptyMethod")
    public static void ignore(@Nullable Object ignoredObject) {
        // intentionally empty
    }

    /**
     * Throws an {@link IllegalArgumentException} if the object
     * is not of the expectedType.
     */
    public static  T checkType(@Nullable Object object, Class expectedType) {
        if (!(expectedType.isInstance(object))) {
            throw new IllegalArgumentException(
                    MessageFormat.format(
                            "Object is not of type {0} (but {1})", //NON-NLS
                            expectedType.getName(), classNameOrNull(object)));
        }

        return expectedType.cast(object);
    }

    /**
     * Returns the {@code value} when it is not {@code null}, otherwise return the {@code otherValue}.
     *
     * In some programming languages this operation is performed by an "Elvis" operator ("?:").
     */
    public static  @NonNull T valueOrElse(@Nullable T value, @NonNull T otherValue) {
        return value != null ? value : otherValue;
    }

    /**
     * Returns the {@code value} when it is not {@code null}, otherwise throw a
     * {@link NullPointerException} with the given message.
     */
    public static  @NonNull T valueOrFail(@Nullable T value, @NonNull String message) {
        if (value == null) {
            throw new NullPointerException(message);
        }
        return value;
    }

    /**
     * Returns the {@code value} when it is not {@code null}, otherwise throw a
     * {@link NullPointerException}.
     */
    public static  @NonNull T valueOrFail(@Nullable T value) {
        if (value == null) {
            throw new NullPointerException();
        }
        return value;
    }


}