https://ant.apache.org/: master POM (The Apache Software Foundation) 
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 *  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
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 *
 *      https://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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package org.apache.tools.ant.taskdefs.condition;

import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.util.StreamUtils;


The Xor condition type to exclusive or operations.
This does not shortcut stuff.

Since:Ant 1.7
/**
 * The <code>Xor</code> condition type to exclusive or operations.
 * This does not shortcut stuff.
 * @since Ant 1.7
 */
public class Xor extends ConditionBase implements Condition {

    
Evaluate the contained conditions.

Throws:
Returns:the result of xoring the conditions together.
/**
     * Evaluate the contained conditions.
     * @return the result of xoring the conditions together.
     * @throws BuildException
     *          if an error occurs.
     */
    @Override
    public boolean eval() throws BuildException {
        // initial state is false
        return StreamUtils.enumerationAsStream(getConditions()).map(Condition::eval)
                .reduce((a, b) -> a ^ b).orElse(Boolean.FALSE);
    }

}