Java tutorial
//package com.java2s; /* * Copyright (c) 2002-2007 Sun Microsystems, Inc. All rights reserved. * * The Sun Project JXTA(TM) Software License * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * 1. Redistributions of source code must retain the above copyright notice, * this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * 3. The end-user documentation included with the redistribution, if any, must * include the following acknowledgment: "This product includes software * developed by Sun Microsystems, Inc. for JXTA(TM) technology." * Alternately, this acknowledgment may appear in the software itself, if * and wherever such third-party acknowledgments normally appear. * * 4. 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IN NO EVENT SHALL SUN * MICROSYSTEMS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * * JXTA is a registered trademark of Sun Microsystems, Inc. in the United * States and other countries. * * Please see the license information page at : * <http://www.jxta.org/project/www/license.html> for instructions on use of * the license in source files. * * ==================================================================== * * This software consists of voluntary contributions made by many individuals * on behalf of Project JXTA. For more information on Project JXTA, please see * http://www.jxta.org. * * This license is based on the BSD license adopted by the Apache Foundation. */ public class Main { /** Return the result of comparing all significant fields. <P>Both <tt>Object[]</tt> parameters are the same size. Each includes all fields that have been deemed by the caller to contribute to the <tt>equals</tt> method. <em>None of those fields are array fields.</em> The order is the same in both arrays, in the sense that the Nth item in each array corresponds to the same underlying field. The caller controls the order in which fields are compared simply through the iteration order of these two arguments. <P>If a primitive field is significant, then it must be converted to a corresponding wrapper <tt>Object</tt> by the caller. */ static public boolean equalsFor(Object[] aThisSignificantFields, Object[] aThatSignificantFields) { //(varargs can be used for final arg only) if (aThisSignificantFields.length != aThatSignificantFields.length) { throw new IllegalArgumentException( "Array lengths do not match. 'This' length is " + aThisSignificantFields.length + ", while 'That' length is " + aThatSignificantFields.length + "."); } boolean result = true; for (int idx = 0; idx < aThisSignificantFields.length; ++idx) { if (!areEqual(aThisSignificantFields[idx], aThatSignificantFields[idx])) { result = false; break; } } return result; } /** Equals for <tt>boolean</tt> fields. */ static public boolean areEqual(boolean aThis, boolean aThat) { return aThis == aThat; } /** Equals for <tt>char</tt> fields. */ static public boolean areEqual(char aThis, char aThat) { return aThis == aThat; } /** Equals for <tt>long</tt> fields. <P>Note that <tt>byte</tt>, <tt>short</tt>, and <tt>int</tt> are handled by this method, through implicit conversion. */ static public boolean areEqual(long aThis, long aThat) { return aThis == aThat; } /** Equals for <tt>float</tt> fields. */ static public boolean areEqual(float aThis, float aThat) { return Float.floatToIntBits(aThis) == Float.floatToIntBits(aThat); } /** Equals for <tt>double</tt> fields. */ static public boolean areEqual(double aThis, double aThat) { return Double.doubleToLongBits(aThis) == Double.doubleToLongBits(aThat); } /** Equals for possibly-<tt>null</tt> object field. <P><em>Does not include arrays</em>. (This restriction will likely be removed in a future version.) */ static public boolean areEqual(Object aThis, Object aThat) { if (isArray(aThis) || isArray(aThat)) { throw new IllegalArgumentException("This method does not currently support arrays."); } return (aThis == null) ? (aThat == null) : aThis.equals(aThat); } private static boolean isArray(Object aObject) { return (aObject != null) && aObject.getClass().isArray(); } }