Converts a String to a Boolean throwing an exception if no match.
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* 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
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*
* http://www.apache.org/licenses/LICENSE-2.0
*
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* distributed under the License is distributed on an "AS IS" BASIS,
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/**
* <p>Operations on boolean primitives and Boolean objects.</p>
*
* <p>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.</p>
*
* @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 {
/**
* <p>Converts a String to a Boolean throwing an exception if no match.</p>
*
* <pre>
* BooleanUtils.toBooleanObject("true", "true", "false", "null") = Boolean.TRUE
* BooleanUtils.toBooleanObject("false", "true", "false", "null") = Boolean.FALSE
* BooleanUtils.toBooleanObject("null", "true", "false", "null") = null
* </pre>
*
* @param str the String to check
* @param trueString the String to match for <code>true</code>
* (case sensitive), may be <code>null</code>
* @param falseString the String to match for <code>false</code>
* (case sensitive), may be <code>null</code>
* @param nullString the String to match for <code>null</code>
* (case sensitive), may be <code>null</code>
* @return the Boolean value of the string,
* <code>null</code> if either the String matches <code>nullString</code>
* or if <code>null</code> input and <code>nullString</code> is
* <code>null</code>
* @throws IllegalArgumentException if the String doesn't match
*/
public static Boolean toBooleanObject(String str, String trueString, String falseString, String nullString) {
if (str == null) {
if (trueString == null) {
return Boolean.TRUE;
} else if (falseString == null) {
return Boolean.FALSE;
} else if (nullString == null) {
return null;
}
} else if (str.equals(trueString)) {
return Boolean.TRUE;
} else if (str.equals(falseString)) {
return Boolean.FALSE;
} else if (str.equals(nullString)) {
return null;
}
// no match
throw new IllegalArgumentException("The String did not match any specified value");
}
}