# AndFactory.java

    /*
     *  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.
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    package org.apache.synapse.commons.evaluators.config;

    import org.apache.synapse.commons.evaluators.Evaluator;
    import org.apache.synapse.commons.evaluators.EvaluatorException;
    import org.apache.synapse.commons.evaluators.AndEvaluator;
    import org.apache.axiom.om.OMElement;
    import org.apache.commons.logging.Log;
    import org.apache.commons.logging.LogFactory;

    import java.util.Iterator;
    import java.util.List;
    import java.util.ArrayList;

    /**
     * <p>This factory creates a {@link AndEvaluator}. This factory expects the
     * following XML configuration.</p>
     * <pre>
     * &lt;and&gt;
     *     two or more evaluators
     * &lt;and&gt;
     * </pre>
     */

    public class AndFactory implements EvaluatorFactory {
        private Log log = LogFactory.getLog(AndFactory.class);

        public Evaluator create(OMElement e) throws EvaluatorException {
            AndEvaluator o = new AndEvaluator();

            Iterator it = e.getChildElements();

            List<Evaluator> evaluators = new ArrayList<Evaluator>();

            while (it.hasNext()) {
                OMElement evaluatorElement = (OMElement) it.next();

                EvaluatorFactory ef = EvaluatorFactoryFinder.getInstance().
                        findEvaluatorFactory(evaluatorElement.getLocalName());

                if (ef == null) {
                    handleException("Invalid configuration element: " +
                            evaluatorElement.getLocalName());
                    return null;
                }

                Evaluator evaluator = ef.create(evaluatorElement);
                evaluators.add(evaluator);
            }

            if (evaluators.size() > 1) {
                o.setEvaluators(evaluators.toArray(new Evaluator[evaluators.size()]));
            } else {
                handleException("Two or more expressions " +
                        "should be provided under And");
                return null;
            }
            return o;
        }

        private void handleException(String message) throws EvaluatorException {
            log.error(message);
            throw new EvaluatorException(message);
        }
    }