ObjectUtils.java

/**
 * The MIT License (MIT)
 * Copyright (c) 2013 Signavio, OMG BPMN Model Interchange Working Group
 *
 * 
 * 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.omg.bpmn.miwg.xmlCompare.util;

public class ObjectUtils {

	/**
	 * Checks whether any of the given parameters is null. If one is found, then an exception is thrown.
	 * 
	 * @param parameters an arbitrary number of objects to be checked for null-safety
	 * @throws NullPointerException is any given parameter is null
	 */
	public static void checkNonNull(final Object... parameters) throws NullPointerException {
		if (parameters == null || parameters.length == 0) {
			return;
		}

		for (int i = 0; i < parameters.length; i++) {
			if (parameters[i] == null) {
				throw new NullPointerException("Parameter " + (i + 1));
			}
		}
	}

	/**
	 * <p>
	 * Compares two objects for equality, where either one or both objects may be {@code null}.
	 * </p>
	 * 
	 * <pre>
	 * ObjectUtils.equals(null, null)                  = true
	 * ObjectUtils.equals(null, "")                    = false
	 * ObjectUtils.equals("", null)                    = false
	 * ObjectUtils.equals("", "")                      = true
	 * ObjectUtils.equals(Boolean.TRUE, null)          = false
	 * ObjectUtils.equals(Boolean.TRUE, "true")        = false
	 * ObjectUtils.equals(Boolean.TRUE, Boolean.TRUE)  = true
	 * ObjectUtils.equals(Boolean.TRUE, Boolean.FALSE) = false
	 * </pre>
	 * 
	 * @param object1 the first object, may be {@code null}
	 * @param object2 the second object, may be {@code null}
	 * @return {@code true} if the values of both objects are the same
	 */
	public static boolean equals(final Object object1, final Object object2) {
		if (object1 == object2) {
			return true;
		}
		if ((object1 == null) || (object2 == null)) {
			return false;
		}
		return object1.equals(object2);
	}
}