Checks that the String does not contain certain characters.
/** * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You 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. */ /** * <p>Operations on {@link java.lang.String} that are * <code>null</code> safe.</p> * * @see java.lang.String * @author <a href="http://jakarta.apache.org/turbine/">Apache Jakarta Turbine</a> * @author <a href="mailto:jon@latchkey.com">Jon S. Stevens</a> * @author Daniel L. Rall * @author <a href="mailto:gcoladonato@yahoo.com">Greg Coladonato</a> * @author <a href="mailto:ed@apache.org">Ed Korthof</a> * @author <a href="mailto:rand_mcneely@yahoo.com">Rand McNeely</a> * @author Stephen Colebourne * @author <a href="mailto:fredrik@westermarck.com">Fredrik Westermarck</a> * @author Holger Krauth * @author <a href="mailto:alex@purpletech.com">Alexander Day Chaffee</a> * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a> * @author Arun Mammen Thomas * @author Gary Gregory * @author Phil Steitz * @author Al Chou * @author Michael Davey * @author Reuben Sivan * @author Chris Hyzer * @author Scott Johnson * @since 1.0 * @version $Id: StringUtils.java 635447 2008-03-10 06:27:09Z bayard $ */ public class Main { /** * <p>Checks that the String does not contain certain characters.</p> * * <p>A <code>null</code> String will return <code>true</code>. * A <code>null</code> invalid character array will return <code>true</code>. * An empty String ("") always returns true.</p> * * <pre> * StringUtils.containsNone(null, *) = true * StringUtils.containsNone(*, null) = true * StringUtils.containsNone("", *) = true * StringUtils.containsNone("ab", "") = true * StringUtils.containsNone("abab", "xyz") = true * StringUtils.containsNone("ab1", "xyz") = true * StringUtils.containsNone("abz", "xyz") = false * </pre> * * @param str the String to check, may be null * @param invalidChars a String of invalid chars, may be null * @return true if it contains none of the invalid chars, or is null * @since 2.0 */ public static boolean containsNone(String str, String invalidChars) { if (str == null || invalidChars == null) { return true; } return containsNone(str, invalidChars.toCharArray()); } // ContainsNone //----------------------------------------------------------------------- /** * <p>Checks that the String does not contain certain characters.</p> * * <p>A <code>null</code> String will return <code>true</code>. * A <code>null</code> invalid character array will return <code>true</code>. * An empty String ("") always returns true.</p> * * <pre> * StringUtils.containsNone(null, *) = true * StringUtils.containsNone(*, null) = true * StringUtils.containsNone("", *) = true * StringUtils.containsNone("ab", '') = true * StringUtils.containsNone("abab", 'xyz') = true * StringUtils.containsNone("ab1", 'xyz') = true * StringUtils.containsNone("abz", 'xyz') = false * </pre> * * @param str the String to check, may be null * @param invalidChars an array of invalid chars, may be null * @return true if it contains none of the invalid chars, or is null * @since 2.0 */ public static boolean containsNone(String str, char[] invalidChars) { if (str == null || invalidChars == null) { return true; } int strSize = str.length(); int validSize = invalidChars.length; for (int i = 0; i < strSize; i++) { char ch = str.charAt(i); for (int j = 0; j < validSize; j++) { if (invalidChars[j] == ch) { return false; } } } return true; } // ---------------------------------------------------------------------- /** * <p>Checks if an array of Objects is empty or <code>null</code>.</p> * * @param array the array to test * @return <code>true</code> if the array is empty or <code>null</code> * @since 2.1 */ public static boolean isEmpty(char[] array) { if (array == null || array.length == 0) { return true; } return false; } // Empty checks //----------------------------------------------------------------------- /** * <p>Checks if a String is empty ("") or null.</p> * * <pre> * StringUtils.isEmpty(null) = true * StringUtils.isEmpty("") = true * StringUtils.isEmpty(" ") = false * StringUtils.isEmpty("bob") = false * StringUtils.isEmpty(" bob ") = false * </pre> * * <p>NOTE: This method changed in Lang version 2.0. * It no longer trims the String. * That functionality is available in isBlank().</p> * * @param str the String to check, may be null * @return <code>true</code> if the String is empty or null */ public static boolean isEmpty(String str) { return str == null || str.length() == 0; } }