All Downloads are FREE. Search and download functionalities are using the official Maven repository.

net.hasor.utils.BooleanUtils Maven / Gradle / Ivy

There is a newer version: 4.2.5
Show newest version
/*
 * 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.
 */
package net.hasor.utils;
/**
 * 

Operations on boolean primitives and Boolean objects.

* *

This class tries to handle null input gracefully. * An exception will not be thrown for a null input. * Each method documents its behaviour in more detail.

* *

#ThreadSafe#

* @author Apache Software Foundation * @author Matthew Hawthorne * @author Gary Gregory * @since 2.0 * @version $Id: BooleanUtils.java 1057037 2011-01-09 21:35:32Z niallp $ */ public class BooleanUtils { /** *

BooleanUtils instances should NOT be constructed in standard programming. * Instead, the class should be used as BooleanUtils.toBooleanObject(true);.

* *

This constructor is public to permit tools that require a JavaBean instance * to operate.

*/ public BooleanUtils() { super(); } // Boolean utilities //-------------------------------------------------------------------------- /** *

Negates the specified boolean.

* *

If null is passed in, null will be returned.

* *
     *   BooleanUtils.negate(Boolean.TRUE)  = Boolean.FALSE;
     *   BooleanUtils.negate(Boolean.FALSE) = Boolean.TRUE;
     *   BooleanUtils.negate(null)          = null;
     * 
* * @param bool the Boolean to negate, may be null * @return the negated Boolean, or null if null input */ public static Boolean negate(Boolean bool) { if (bool == null) { return null; } return (bool.booleanValue() ? Boolean.FALSE : Boolean.TRUE); } // boolean Boolean methods //----------------------------------------------------------------------- /** *

Checks if a Boolean value is true, * handling null by returning false.

* *
     *   BooleanUtils.isTrue(Boolean.TRUE)  = true
     *   BooleanUtils.isTrue(Boolean.FALSE) = false
     *   BooleanUtils.isTrue(null)          = false
     * 
* * @param bool the boolean to check, null returns false * @return true only if the input is non-null and true * @since 2.1 */ public static boolean isTrue(Boolean bool) { if (bool == null) { return false; } return bool.booleanValue() ? true : false; } /** *

Checks if a Boolean value is not true, * handling null by returning true.

* *
     *   BooleanUtils.isNotTrue(Boolean.TRUE)  = false
     *   BooleanUtils.isNotTrue(Boolean.FALSE) = true
     *   BooleanUtils.isNotTrue(null)          = true
     * 
* * @param bool the boolean to check, null returns true * @return true if the input is null or false * @since 2.3 */ public static boolean isNotTrue(Boolean bool) { return !isTrue(bool); } /** *

Checks if a Boolean value is false, * handling null by returning false.

* *
     *   BooleanUtils.isFalse(Boolean.TRUE)  = false
     *   BooleanUtils.isFalse(Boolean.FALSE) = true
     *   BooleanUtils.isFalse(null)          = false
     * 
* * @param bool the boolean to check, null returns false * @return true only if the input is non-null and false * @since 2.1 */ public static boolean isFalse(Boolean bool) { if (bool == null) { return false; } return bool.booleanValue() ? false : true; } /** *

Checks if a Boolean value is not false, * handling null by returning true.

* *
     *   BooleanUtils.isNotFalse(Boolean.TRUE)  = true
     *   BooleanUtils.isNotFalse(Boolean.FALSE) = false
     *   BooleanUtils.isNotFalse(null)          = true
     * 
* * @param bool the boolean to check, null returns true * @return true if the input is null or true * @since 2.3 */ public static boolean isNotFalse(Boolean bool) { return !isFalse(bool); } //----------------------------------------------------------------------- /** *

Boolean factory that avoids creating new Boolean objecs all the time.

* *

This method was added to JDK1.4 but is available here for earlier JDKs.

* *
     *   BooleanUtils.toBooleanObject(false) = Boolean.FALSE
     *   BooleanUtils.toBooleanObject(true)  = Boolean.TRUE
     * 
* * @param bool the boolean to convert * @return Boolean.TRUE or Boolean.FALSE as appropriate */ public static Boolean toBooleanObject(boolean bool) { return bool ? Boolean.TRUE : Boolean.FALSE; } /** *

Converts a Boolean to a boolean handling null * by returning false.

* *
     *   BooleanUtils.toBoolean(Boolean.TRUE)  = true
     *   BooleanUtils.toBoolean(Boolean.FALSE) = false
     *   BooleanUtils.toBoolean(null)          = false
     * 
* * @param bool the boolean to convert * @return true or false, * null returns false */ public static boolean toBoolean(Boolean bool) { if (bool == null) { return false; } return bool.booleanValue() ? true : false; } /** *

Converts a Boolean to a boolean handling null.

* *
     *   BooleanUtils.toBooleanDefaultIfNull(Boolean.TRUE, false) = true
     *   BooleanUtils.toBooleanDefaultIfNull(Boolean.FALSE, true) = false
     *   BooleanUtils.toBooleanDefaultIfNull(null, true)          = true
     * 
* * @param bool the boolean to convert * @param valueIfNull the boolean value to return if null * @return true or false */ public static boolean toBooleanDefaultIfNull(Boolean bool, boolean valueIfNull) { if (bool == null) { return valueIfNull; } return bool.booleanValue() ? true : false; } // Integer to Boolean methods //----------------------------------------------------------------------- /** *

Converts an int to a boolean using the convention that zero * is false.

* *
     *   BooleanUtils.toBoolean(0) = false
     *   BooleanUtils.toBoolean(1) = true
     *   BooleanUtils.toBoolean(2) = true
     * 
* * @param value the int to convert * @return true if non-zero, false * if zero */ public static boolean toBoolean(int value) { return value == 0 ? false : true; } /** *

Converts an int to a Boolean using the convention that zero * is false.

* *
     *   BooleanUtils.toBoolean(0) = Boolean.FALSE
     *   BooleanUtils.toBoolean(1) = Boolean.TRUE
     *   BooleanUtils.toBoolean(2) = Boolean.TRUE
     * 
* * @param value the int to convert * @return Boolean.TRUE if non-zero, Boolean.FALSE if zero, * null if null */ public static Boolean toBooleanObject(int value) { return value == 0 ? Boolean.FALSE : Boolean.TRUE; } /** *

Converts an Integer to a Boolean using the convention that zero * is false.

* *

null will be converted to null.

* *
     *   BooleanUtils.toBoolean(new Integer(0))    = Boolean.FALSE
     *   BooleanUtils.toBoolean(new Integer(1))    = Boolean.TRUE
     *   BooleanUtils.toBoolean(new Integer(null)) = null
     * 
* * @param value the Integer to convert * @return Boolean.TRUE if non-zero, Boolean.FALSE if zero, * null if null input */ public static Boolean toBooleanObject(Integer value) { if (value == null) { return null; } return value.intValue() == 0 ? Boolean.FALSE : Boolean.TRUE; } /** *

Converts an int to a boolean specifying the conversion values.

* *
     *   BooleanUtils.toBoolean(0, 1, 0) = false
     *   BooleanUtils.toBoolean(1, 1, 0) = true
     *   BooleanUtils.toBoolean(2, 1, 2) = false
     *   BooleanUtils.toBoolean(2, 2, 0) = true
     * 
* * @param value the Integer to convert * @param trueValue the value to match for true * @param falseValue the value to match for false * @return true or false * @throws IllegalArgumentException if no match */ public static boolean toBoolean(int value, int trueValue, int falseValue) { if (value == trueValue) { return true; } else if (value == falseValue) { return false; } // no match throw new IllegalArgumentException("The Integer did not match either specified value"); } /** *

Converts an Integer to a boolean specifying the conversion values.

* *
     *   BooleanUtils.toBoolean(new Integer(0), new Integer(1), new Integer(0)) = false
     *   BooleanUtils.toBoolean(new Integer(1), new Integer(1), new Integer(0)) = true
     *   BooleanUtils.toBoolean(new Integer(2), new Integer(1), new Integer(2)) = false
     *   BooleanUtils.toBoolean(new Integer(2), new Integer(2), new Integer(0)) = true
     *   BooleanUtils.toBoolean(null, null, new Integer(0))                     = true
     * 
* * @param value the Integer to convert * @param trueValue the value to match for true, * may be null * @param falseValue the value to match for false, * may be null * @return true or false * @throws IllegalArgumentException if no match */ public static boolean toBoolean(Integer value, Integer trueValue, Integer falseValue) { if (value == null) { if (trueValue == null) { return true; } else if (falseValue == null) { return false; } } else if (value.equals(trueValue)) { return true; } else if (value.equals(falseValue)) { return false; } // no match throw new IllegalArgumentException("The Integer did not match either specified value"); } /** *

Converts an int to a Boolean specifying the conversion values.

* *
     *   BooleanUtils.toBooleanObject(0, 0, 2, 3) = Boolean.TRUE
     *   BooleanUtils.toBooleanObject(2, 1, 2, 3) = Boolean.FALSE
     *   BooleanUtils.toBooleanObject(3, 1, 2, 3) = null
     * 
* * @param value the Integer to convert * @param trueValue the value to match for true * @param falseValue the value to match for false * @param nullValue the value to to match for null * @return Boolean.TRUE, Boolean.FALSE, or null * @throws IllegalArgumentException if no match */ public static Boolean toBooleanObject(int value, int trueValue, int falseValue, int nullValue) { if (value == trueValue) { return Boolean.TRUE; } else if (value == falseValue) { return Boolean.FALSE; } else if (value == nullValue) { return null; } // no match throw new IllegalArgumentException("The Integer did not match any specified value"); } /** *

Converts an Integer to a Boolean specifying the conversion values.

* *
     *   BooleanUtils.toBooleanObject(new Integer(0), new Integer(0), new Integer(2), new Integer(3)) = Boolean.TRUE
     *   BooleanUtils.toBooleanObject(new Integer(2), new Integer(1), new Integer(2), new Integer(3)) = Boolean.FALSE
     *   BooleanUtils.toBooleanObject(new Integer(3), new Integer(1), new Integer(2), new Integer(3)) = null
     * 
* * @param value the Integer to convert * @param trueValue the value to match for true, * may be null * @param falseValue the value to match for false, * may be null * @param nullValue the value to to match for null, * may be null * @return Boolean.TRUE, Boolean.FALSE, or null * @throws IllegalArgumentException if no match */ public static Boolean toBooleanObject(Integer value, Integer trueValue, Integer falseValue, Integer nullValue) { if (value == null) { if (trueValue == null) { return Boolean.TRUE; } else if (falseValue == null) { return Boolean.FALSE; } else if (nullValue == null) { return null; } } else if (value.equals(trueValue)) { return Boolean.TRUE; } else if (value.equals(falseValue)) { return Boolean.FALSE; } else if (value.equals(nullValue)) { return null; } // no match throw new IllegalArgumentException("The Integer did not match any specified value"); } // Boolean to Integer methods //----------------------------------------------------------------------- /** *

Converts a boolean to an int using the convention that * zero is false.

* *
     *   BooleanUtils.toInteger(true)  = 1
     *   BooleanUtils.toInteger(false) = 0
     * 
* * @param bool the boolean to convert * @return one if true, zero if false */ public static int toInteger(boolean bool) { return bool ? 1 : 0; } /** *

Converts a boolean to an int specifying the conversion values.

* *
     *   BooleanUtils.toInteger(true, 1, 0)  = 1
     *   BooleanUtils.toInteger(false, 1, 0) = 0
     * 
* * @param bool the to convert * @param trueValue the value to return if true * @param falseValue the value to return if false * @return the appropriate value */ public static int toInteger(boolean bool, int trueValue, int falseValue) { return bool ? trueValue : falseValue; } /** *

Converts a Boolean to an int specifying the conversion values.

* *
     *   BooleanUtils.toInteger(Boolean.TRUE, 1, 0, 2)  = 1
     *   BooleanUtils.toInteger(Boolean.FALSE, 1, 0, 2) = 0
     *   BooleanUtils.toInteger(null, 1, 0, 2)          = 2
     * 
* * @param bool the Boolean to convert * @param trueValue the value to return if true * @param falseValue the value to return if false * @param nullValue the value to return if null * @return the appropriate value */ public static int toInteger(Boolean bool, int trueValue, int falseValue, int nullValue) { if (bool == null) { return nullValue; } return bool.booleanValue() ? trueValue : falseValue; } /** *

Converts a boolean to an Integer specifying the conversion values.

* *
     *   BooleanUtils.toIntegerObject(true, new Integer(1), new Integer(0))  = new Integer(1)
     *   BooleanUtils.toIntegerObject(false, new Integer(1), new Integer(0)) = new Integer(0)
     * 
* * @param bool the to convert * @param trueValue the value to return if true, * may be null * @param falseValue the value to return if false, * may be null * @return the appropriate value */ public static Integer toIntegerObject(boolean bool, Integer trueValue, Integer falseValue) { return bool ? trueValue : falseValue; } /** *

Converts a Boolean to an Integer specifying the conversion values.

* *
     *   BooleanUtils.toIntegerObject(Boolean.TRUE, new Integer(1), new Integer(0), new Integer(2))  = new Integer(1)
     *   BooleanUtils.toIntegerObject(Boolean.FALSE, new Integer(1), new Integer(0), new Integer(2)) = new Integer(0)
     *   BooleanUtils.toIntegerObject(null, new Integer(1), new Integer(0), new Integer(2))          = new Integer(2)
     * 
* * @param bool the Boolean to convert * @param trueValue the value to return if true, * may be null * @param falseValue the value to return if false, * may be null * @param nullValue the value to return if null, * may be null * @return the appropriate value */ public static Integer toIntegerObject(Boolean bool, Integer trueValue, Integer falseValue, Integer nullValue) { if (bool == null) { return nullValue; } return bool.booleanValue() ? trueValue : falseValue; } // String to Boolean methods //----------------------------------------------------------------------- /** *

Converts a String to a Boolean.

* *

'true', 'on' or 'yes' * (case insensitive) will return true. * 'false', 'off' or 'no' * (case insensitive) will return false. * Otherwise, null is returned.

* *
     *   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
     * 
* * @param str the String to check * @return the Boolean value of the string, * null if no match or null input */ public static Boolean toBooleanObject(String str) { // Previously used equalsIgnoreCase, which was fast for interned 'true'. // Non interned 'true' matched 15 times slower. // // Optimisation provides same performance as before for interned 'true'. // Similar performance for null, 'false', and other strings not length 2/3/4. // 'true'/'TRUE' match 4 times slower, 'tRUE'/'True' 7 times slower. if (str == null) { return null; } if ("true".equals(str)) { return Boolean.TRUE; } switch (str.length()) { case 1: { char ch0 = str.charAt(0); if ((ch0 == 'y' || ch0 == 'Y') || (ch0 == 't' || ch0 == 'T')) { return Boolean.TRUE; } if ((ch0 == 'n' || ch0 == 'N') || (ch0 == 'f' || ch0 == 'F')) { return Boolean.FALSE; } break; } case 2: { char ch0 = str.charAt(0); char ch1 = str.charAt(1); if ((ch0 == 'o' || ch0 == 'O') && (ch1 == 'n' || ch1 == 'N')) { return Boolean.TRUE; } if ((ch0 == 'n' || ch0 == 'N') && (ch1 == 'o' || ch1 == 'O')) { return Boolean.FALSE; } break; } case 3: { char ch0 = str.charAt(0); char ch1 = str.charAt(1); char ch2 = str.charAt(2); if ((ch0 == 'y' || ch0 == 'Y') && (ch1 == 'e' || ch1 == 'E') && (ch2 == 's' || ch2 == 'S')) { return Boolean.TRUE; } if ((ch0 == 'o' || ch0 == 'O') && (ch1 == 'f' || ch1 == 'F') && (ch2 == 'f' || ch2 == 'F')) { return Boolean.FALSE; } break; } case 4: { char ch0 = str.charAt(0); char ch1 = str.charAt(1); char ch2 = str.charAt(2); char ch3 = str.charAt(3); if ((ch0 == 't' || ch0 == 'T') && (ch1 == 'r' || ch1 == 'R') && (ch2 == 'u' || ch2 == 'U') && (ch3 == 'e' || ch3 == 'E')) { return Boolean.TRUE; } break; } case 5: { char ch0 = str.charAt(0); char ch1 = str.charAt(1); char ch2 = str.charAt(2); char ch3 = str.charAt(3); char ch4 = str.charAt(4); if ((ch0 == 'f' || ch0 == 'F') && (ch1 == 'a' || ch1 == 'A') && (ch2 == 'l' || ch2 == 'L') && (ch3 == 's' || ch3 == 'S') && (ch4 == 'e' || ch4 == 'E')) { return Boolean.FALSE; } break; } } return null; } /** *

Converts a String to a Boolean throwing an exception if no match.

* *
     *   BooleanUtils.toBooleanObject("true", "true", "false", "null")  = Boolean.TRUE
     *   BooleanUtils.toBooleanObject("false", "true", "false", "null") = Boolean.FALSE
     *   BooleanUtils.toBooleanObject("null", "true", "false", "null")  = null
     * 
* * @param str the String to check * @param trueString the String to match for true * (case sensitive), may be null * @param falseString the String to match for false * (case sensitive), may be null * @param nullString the String to match for null * (case sensitive), may be null * @return the Boolean value of the string, * null if either the String matches nullString * or if null input and nullString is * null * @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"); } // String to boolean methods //----------------------------------------------------------------------- /** *

Converts a String to a boolean (optimised for performance).

* *

'true', 'on' or 'yes' * (case insensitive) will return true. Otherwise, * false is returned.

* *

This method performs 4 times faster (JDK1.4) than * Boolean.valueOf(String). However, this method accepts * 'on' and 'yes' as true values. * *

     *   BooleanUtils.toBoolean(null)    = false
     *   BooleanUtils.toBoolean("true")  = true
     *   BooleanUtils.toBoolean("TRUE")  = true
     *   BooleanUtils.toBoolean("tRUe")  = true
     *   BooleanUtils.toBoolean("on")    = true
     *   BooleanUtils.toBoolean("yes")   = true
     *   BooleanUtils.toBoolean("false") = false
     *   BooleanUtils.toBoolean("x gti") = false
     * 
* * @param str the String to check * @return the boolean value of the string, false if no match or the String is null */ public static boolean toBoolean(String str) { return toBoolean(toBooleanObject(str)); } /** *

Converts a String to a Boolean throwing an exception if no match found.

* *

null is returned if there is no match.

* *
     *   BooleanUtils.toBoolean("true", "true", "false")  = true
     *   BooleanUtils.toBoolean("false", "true", "false") = false
     * 
* * @param str the String to check * @param trueString the String to match for true * (case sensitive), may be null * @param falseString the String to match for false * (case sensitive), may be null * @return the boolean value of the string * @throws IllegalArgumentException if the String doesn't match */ public static boolean toBoolean(String str, String trueString, String falseString) { if (str == null) { if (trueString == null) { return true; } else if (falseString == null) { return false; } } else if (str.equals(trueString)) { return true; } else if (str.equals(falseString)) { return false; } // no match throw new IllegalArgumentException("The String did not match either specified value"); } // Boolean to String methods //----------------------------------------------------------------------- /** *

Converts a Boolean to a String returning 'true', * 'false', or null.

* *
     *   BooleanUtils.toStringTrueFalse(Boolean.TRUE)  = "true"
     *   BooleanUtils.toStringTrueFalse(Boolean.FALSE) = "false"
     *   BooleanUtils.toStringTrueFalse(null)          = null;
     * 
* * @param bool the Boolean to check * @return 'true', 'false', * or null */ public static String toStringTrueFalse(Boolean bool) { return toString(bool, "true", "false", null); } /** *

Converts a Boolean to a String returning 'on', * 'off', or null.

* *
     *   BooleanUtils.toStringOnOff(Boolean.TRUE)  = "on"
     *   BooleanUtils.toStringOnOff(Boolean.FALSE) = "off"
     *   BooleanUtils.toStringOnOff(null)          = null;
     * 
* * @param bool the Boolean to check * @return 'on', 'off', * or null */ public static String toStringOnOff(Boolean bool) { return toString(bool, "on", "off", null); } /** *

Converts a Boolean to a String returning 'yes', * 'no', or null.

* *
     *   BooleanUtils.toStringYesNo(Boolean.TRUE)  = "yes"
     *   BooleanUtils.toStringYesNo(Boolean.FALSE) = "no"
     *   BooleanUtils.toStringYesNo(null)          = null;
     * 
* * @param bool the Boolean to check * @return 'yes', 'no', * or null */ public static String toStringYesNo(Boolean bool) { return toString(bool, "yes", "no", null); } /** *

Converts a Boolean to a String returning one of the input Strings.

* *
     *   BooleanUtils.toString(Boolean.TRUE, "true", "false", null)   = "true"
     *   BooleanUtils.toString(Boolean.FALSE, "true", "false", null)  = "false"
     *   BooleanUtils.toString(null, "true", "false", null)           = null;
     * 
* * @param bool the Boolean to check * @param trueString the String to return if true, * may be null * @param falseString the String to return if false, * may be null * @param nullString the String to return if null, * may be null * @return one of the three input Strings */ public static String toString(Boolean bool, String trueString, String falseString, String nullString) { if (bool == null) { return nullString; } return bool.booleanValue() ? trueString : falseString; } // boolean to String methods //----------------------------------------------------------------------- /** *

Converts a boolean to a String returning 'true' * or 'false'.

* *
     *   BooleanUtils.toStringTrueFalse(true)   = "true"
     *   BooleanUtils.toStringTrueFalse(false)  = "false"
     * 
* * @param bool the Boolean to check * @return 'true', 'false', * or null */ public static String toStringTrueFalse(boolean bool) { return toString(bool, "true", "false"); } /** *

Converts a boolean to a String returning 'on' * or 'off'.

* *
     *   BooleanUtils.toStringOnOff(true)   = "on"
     *   BooleanUtils.toStringOnOff(false)  = "off"
     * 
* * @param bool the Boolean to check * @return 'on', 'off', * or null */ public static String toStringOnOff(boolean bool) { return toString(bool, "on", "off"); } /** *

Converts a boolean to a String returning 'yes' * or 'no'.

* *
     *   BooleanUtils.toStringYesNo(true)   = "yes"
     *   BooleanUtils.toStringYesNo(false)  = "no"
     * 
* * @param bool the Boolean to check * @return 'yes', 'no', * or null */ public static String toStringYesNo(boolean bool) { return toString(bool, "yes", "no"); } /** *

Converts a boolean to a String returning one of the input Strings.

* *
     *   BooleanUtils.toString(true, "true", "false")   = "true"
     *   BooleanUtils.toString(false, "true", "false")  = "false"
     * 
* * @param bool the Boolean to check * @param trueString the String to return if true, * may be null * @param falseString the String to return if false, * may be null * @return one of the two input Strings */ public static String toString(boolean bool, String trueString, String falseString) { return bool ? trueString : falseString; } // xor methods // ---------------------------------------------------------------------- /** *

Performs an xor on a set of booleans.

* *
     *   BooleanUtils.xor(new boolean[] { true, true })   = false
     *   BooleanUtils.xor(new boolean[] { false, false }) = false
     *   BooleanUtils.xor(new boolean[] { true, false })  = true
     * 
* * @param array an array of booleans * @return true if the xor is successful. * @throws IllegalArgumentException if array is null * @throws IllegalArgumentException if array is empty. */ public static boolean xor(boolean[] array) { // Validates input if (array == null) { throw new IllegalArgumentException("The Array must not be null"); } else if (array.length == 0) { throw new IllegalArgumentException("Array is empty"); } // Loops through array, comparing each item int trueCount = 0; for (int i = 0; i < array.length; i++) { // If item is true, and trueCount is < 1, increments count // Else, xor fails if (array[i]) { if (trueCount < 1) { trueCount++; } else { return false; } } } // Returns true if there was exactly 1 true item return trueCount == 1; } /** *

Performs an xor on an array of Booleans.

* *
     *   BooleanUtils.xor(new Boolean[] { Boolean.TRUE, Boolean.TRUE })   = Boolean.FALSE
     *   BooleanUtils.xor(new Boolean[] { Boolean.FALSE, Boolean.FALSE }) = Boolean.FALSE
     *   BooleanUtils.xor(new Boolean[] { Boolean.TRUE, Boolean.FALSE })  = Boolean.TRUE
     * 
* * @param array an array of Booleans * @return true if the xor is successful. * @throws IllegalArgumentException if array is null * @throws IllegalArgumentException if array is empty. * @throws IllegalArgumentException if array contains a null */ public static Boolean xor(Boolean[] array) { if (array == null) { throw new IllegalArgumentException("The Array must not be null"); } else if (array.length == 0) { throw new IllegalArgumentException("Array is empty"); } boolean[] primitive = null; try { primitive = ArrayUtils.toPrimitive(array); } catch (NullPointerException ex) { throw new IllegalArgumentException("The array must not contain any null elements"); } return xor(primitive) ? Boolean.TRUE : Boolean.FALSE; } // public static boolean isBooleanType(Class targetType) { return targetType.equals(Boolean.class) || targetType.equals(Boolean.TYPE); } }