Java tutorial
/* * 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. */ /** * Operations on boolean primitives and Boolean objects. * * This class tries to handle <code>null</code> input gracefully. * An exception will not be thrown for a <code>null</code> input. * Each method documents its behaviour in more detail. * * @author Stephen Colebourne * @author Matthew Hawthorne * @author Gary Gregory * @since 2.0 * @version $Id: BooleanUtils.java 589050 2007-10-27 05:07:45Z bayard $ */ public class Main { /** * Converts a String to a Boolean. * * <code>'true'</code>, <code>'on'</code> or <code>'yes'</code> * (case insensitive) will return <code>true</code>. * <code>'false'</code>, <code>'off'</code> or <code>'no'</code> * (case insensitive) will return <code>false</code>. * Otherwise, <code>null</code> is returned.</p> * * <pre> * BooleanUtils.toBooleanObject(null) = null * BooleanUtils.toBooleanObject("true") = Boolean.TRUE * BooleanUtils.toBooleanObject("false") = Boolean.FALSE * BooleanUtils.toBooleanObject("on") = Boolean.TRUE * BooleanUtils.toBooleanObject("ON") = Boolean.TRUE * BooleanUtils.toBooleanObject("off") = Boolean.FALSE * BooleanUtils.toBooleanObject("oFf") = Boolean.FALSE * BooleanUtils.toBooleanObject("blue") = null * </pre> * * @param str the String to check * @return the Boolean value of the string, * <code>null</code> if no match or <code>null</code> input */ public static Boolean toBooleanObject(String str) { if ("true".equalsIgnoreCase(str)) { return Boolean.TRUE; } else if ("false".equalsIgnoreCase(str)) { return Boolean.FALSE; } else if ("on".equalsIgnoreCase(str)) { return Boolean.TRUE; } else if ("off".equalsIgnoreCase(str)) { return Boolean.FALSE; } else if ("yes".equalsIgnoreCase(str)) { return Boolean.TRUE; } else if ("no".equalsIgnoreCase(str)) { return Boolean.FALSE; } // no match return null; } }