By the way, I promised some time ago to make a Validate class. Well, here is a first cut at it.
Improvements, disapprovements etc are welcome as usual. /O
package org.apache.commons.lang; /* ==================================================================== * The Apache Software License, Version 1.1 * * Copyright (c) 2002 The Apache Software Foundation. All rights * reserved. * * 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 acknowlegement: * "This product includes software developed by the * Apache Software Foundation (http://www.apache.org/)." * Alternately, this acknowlegement may appear in the software itself, * if and wherever such third-party acknowlegements normally appear. * * 4. The names "The Jakarta Project", "Commons", and "Apache Software * Foundation" must not be used to endorse or promote products derived * from this software without prior written permission. For written * permission, please contact [EMAIL PROTECTED] * * 5. Products derived from this software may not be called "Apache" * nor may "Apache" appear in their names without prior written * permission of the Apache Software Foundation. * * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION 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. * ==================================================================== * * This software consists of voluntary contributions made by many * individuals on behalf of the Apache Software Foundation. For more * information on the Apache Software Foundation, please see * <http://www.apache.org/>. */ import java.util.Collection; import java.util.Iterator; /** This class contains static utility methods for validating arguments. If a argument value is deemed invalid, an IllegalArgumentException is thrown. @author <a href="mailto:[EMAIL PROTECTED]";>Ola Berg</a> @version $Id$ */ public class Validate { /** Throws the exception if the argument is false. This is used when validating according to an arbitrary boolean expression, such as validating a primitive number or using your own custom validation expression. <pre> Validate.isTrue( (i > 0), "The number i is not positive, it is " + i); Validate.isTrue( (myObject.isOk()), "The object " + myObject.toString() + " is not OK"); </pre> @param expression A boolean expression. @param message The exception message you would like to see if the expression is false. @exception IllegalArgumentException Thrown if expression is false, or if the message is null. */ public static void isTrue( boolean expression, String message){ notNull( message, "The provided exception message for isTrue() is null"); if (!expression){ throw new IllegalArgumentException( message); } } /** A version of the {@link #isTrue(boolean,String)} method without the possibility to supply a custom exception message. */ public static void isTrue( boolean expression){ isTrue( expression, "The expression is false"); } /** Throws the exception if the argument is null. @param object An object. @param message The exception message you would like to see if the object is null. @exception IllegalArgumentException Thrown if the object is null, or if the message is null. */ public static void notNull( Object object, String message){ notNull( message, "The provided exception message for notNull() is null"); if (object == null){ throw new IllegalArgumentException( message); } } /** A version of the {@link #notNull(Object,String)} method without the possibility to supply a custom exception message. */ public static void notNull( Object object){ if (object == null){ throw new IllegalArgumentException( "The object is null"); } } /** Throws the exception if the supplied array is empty, after it has been validated using {@link #notNull(Object)}. @param array An array. @param message The exception message you would like to see if the array is empty. @exception IllegalArgumentException Thrown if the array is empty or null, or if the message is null. */ public static void notEmpty( Object [] array, String message){ notNull( array, "The provided array is null"); notNull( message, "The provided exception message for notEmpty() is null"); if (array.length == 0){ throw new IllegalArgumentException( message); } } /** A version of the {@link #notEmpty(Object[],String)} method without the possibility to supply a custom exception message. */ public static void notEmpty( Object [] array){ notEmpty( array, "The provided array is empty"); } /** Throws the exception if the supplied Collection is empty, after it has been validated using {@link #notNull(Object)}. @param collection A collection object. @param message The exception message you would like to see if the collection is empty. @exception IllegalArgumentException Thrown if the collection is empty or null, or if the message is null. */ public static void notEmpty( Collection collection, String message){ notNull( collection, "The provided collection is null"); notNull( message, "The provided exception message for notEmpty() is null"); if (collection.isEmpty()){ throw new IllegalArgumentException( message); } } /** A version of the {@link #notEmpty(Collection,String)} method without the possibility to supply a custom exception message. */ public static void notEmpty( Collection collection){ notEmpty( collection, "The provided collection is empty"); } /** Throws the exception if the supplied String is empty, after it has been validated using {@link #notNull(Object)}. @param string A string. @param message The exception message you would like to see if the string is empty. @exception IllegalArgumentException Thrown if the string is empty or null, or if the message is null. */ public static void notEmpty( String string, String message){ notNull( string, "The provided string is null"); notNull( message, "The provided exception message for notEmpty() is null"); if (string.length() == 0){ throw new IllegalArgumentException( message); } } /** A version of the {@link #notEmpty(String,String)} method without the possibility to supply a custom exception message. */ public static void notEmpty( String string){ notEmpty( string, "The provided string is empty"); } /** Throws the exception if the supplied array contains null elements, after it has been validated using {@link #notNull(Object)}. @param array An array. @param message The exception message you would like to see if the array contains null elements. @exception IllegalArgumentException Thrown if the array is null or contains null elements, or if the message is null. */ public static void noNullElements( Object [] array, String message){ notNull( array, "The provided array is null"); notNull( message, "The provided exception message for noNullElements() is null"); for( int i=0; i<array.length; i++){ if (array[i] == null){ throw new IllegalArgumentException( message); } } } /** A version of the {@link #noNullElements(Object[],String)} method without the possibility to supply a custom exception message. */ public static void noNullElements( Object[] array){ noNullElements( array, "The provided array contains null elements"); } /** Throws the exception if the supplied collection contains null elements, after it has been validated using {@link #notNull(Object)}. @param array An array. @param message The exception message you would like to see if the array contains null elements. @exception IllegalArgumentException Thrown if the array is null or contains null elements, or if the message is null. */ public static void noNullElements( Collection collection, String message){ notNull( collection, "The provided collection is null"); notNull( message, "The provided exception message for noNullElements() is null"); Iterator i = collection.iterator(); while( i.hasNext()){ if (i.next() == null){ throw new IllegalArgumentException( message); } } } /** A version of the {@link #noNullElements(Collection,String)} method without the possibility to supply a custom exception message. */ public static void noNullElements( Collection collection){ noNullElements( collection, "The provided collection contains null elements"); } }
-- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]>
