Converts a String to a Boolean. : Boolean « Data Type « Java Tutorial






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 * 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;
  }
}








2.2.Boolean
2.2.1.java.lang.Boolean
2.2.2.Java boolean value
2.2.3.Boolean Data Type
2.2.4.Boolean Literals
2.2.5.Boolean Variables
2.2.6.Using the boolean type
2.2.7.valueOf(): parse a String to a Boolean object
2.2.8.toString(): return the string representation of a boolean
2.2.9.Convert String to Boolean
2.2.10.Convert Boolean to String
2.2.11.Convert Java boolean Primitive to Boolean object
2.2.12.Convert Java String Object to Boolean Object
2.2.13.Create an Boolean object from boolean value
2.2.14.Compare Two Java boolean Arrays Example
2.2.15.Convert integer to boolean
2.2.16.Convert boolean to integer
2.2.17.Convert boolean value to Boolean
2.2.18.Create a boolean variable from string
2.2.19.Autoboxing/unboxing a Boolean and Character.
2.2.20.Converts a String to a Boolean.
2.2.21.Converts a boolean to a String returning 'yes' or 'no'
2.2.22.Converts an Integer to a boolean specifying the conversion values.
2.2.23.Converts an int to a boolean specifying the conversion values.
2.2.24.Performs an xor on a set of booleans.