Objects.java

/*****************************************************************************
 * Copyright (C) Codehaus.org                                                *
 * ------------------------------------------------------------------------- *
 * 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 net.ion.rosetta.util;

/**
 * Utility functions for any object.
 * 
 * @author Ben Yu
 */
public final class Objects {
	/** Gets the has hcode for {@code obj}. 0 is returned if obj is null. */
	public static int hashCode(Object obj) {
		return obj == null ? 0 : obj.hashCode();
	}

	/**
	 * Compares {@code o1} and {@code o2} for equality. Returns true if both are
	 * {@code null} or {@code o1.equals(o2)}.
	 */
	public static boolean equals(Object o1, Object o2) {
		return o1 == null ? o2 == null : o1.equals(o2);
	}

	/** Checks whether {@code obj} is one of the elements of {@code array}. */
	public static boolean in(Object obj, Object... array) {
		for (Object expected : array) {
			if (obj == expected) {
				return true;
			}
		}
		return false;
	}
}