001/* =================================================== 002 * JFreeSVG : an SVG library for the Java(tm) platform 003 * =================================================== 004 * 005 * (C)opyright 2013-2021, by Object Refinery Limited. All rights reserved. 006 * 007 * Project Info: http://www.jfree.org/jfreesvg/index.html 008 * 009 * This program is free software: you can redistribute it and/or modify 010 * it under the terms of the GNU General Public License as published by 011 * the Free Software Foundation, either version 3 of the License, or 012 * (at your option) any later version. 013 * 014 * This program is distributed in the hope that it will be useful, 015 * but WITHOUT ANY WARRANTY; without even the implied warranty of 016 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 017 * GNU General Public License for more details. 018 * 019 * You should have received a copy of the GNU General Public License 020 * along with this program. If not, see <http://www.gnu.org/licenses/>. 021 * 022 * [Oracle and Java are registered trademarks of Oracle and/or its affiliates. 023 * Other names may be trademarks of their respective owners.] 024 * 025 * If you do not wish to be bound by the terms of the GPL, an alternative 026 * commercial license can be purchased. For details, please see visit the 027 * JFreeSVG home page: 028 * 029 * http://www.jfree.org/jfreesvg 030 * 031 */ 032 033package org.jfree.graphics2d; 034 035/** 036 * A utility class that performs checks for method argument validity. 037 */ 038public class Args { 039 040 private Args() { 041 // no need to instantiate this 042 } 043 044 /** 045 * Checks that an argument is non-{@code null} and throws an 046 * {@code IllegalArgumentException} otherwise. 047 * 048 * @param obj the object to check for {@code null}. 049 * @param ref the text name for the parameter (to include in the exception 050 * message). 051 */ 052 public static void nullNotPermitted(Object obj, String ref) { 053 if (obj == null) { 054 throw new IllegalArgumentException("Null '" + ref + "' argument."); 055 } 056 } 057 058 /** 059 * Checks an array to ensure it has the correct length and throws an 060 * {@code IllegalArgumentException} if it does not. 061 * 062 * @param length the required length. 063 * @param array the array to check. 064 * @param ref the text name of the array parameter (to include in the 065 * exception message). 066 */ 067 public static void arrayMustHaveLength(int length, boolean[] array, 068 String ref) { 069 nullNotPermitted(array, "array"); 070 if (array.length != length) { 071 throw new IllegalArgumentException("Array '" + ref 072 + "' requires length " + length); 073 } 074 } 075 076 /** 077 * Checks an array to ensure it has the correct length and throws an 078 * {@code IllegalArgumentException} if it does not. 079 * 080 * @param length the required length. 081 * @param array the array to check ({@code null} not permitted). 082 * @param ref the text name of the array parameter (to include in the 083 * exception message). 084 */ 085 public static void arrayMustHaveLength(int length, double[] array, 086 String ref) { 087 nullNotPermitted(array, "array"); 088 if (array.length != length) { 089 throw new IllegalArgumentException("Array '" + ref 090 + "' requires length " + length); 091 } 092 } 093}