# PropertyHelper.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.
     */

    package org.apache.synapse.commons.util;

    import org.apache.axiom.om.OMElement;
    import org.apache.commons.logging.Log;
    import org.apache.commons.logging.LogFactory;
    import org.apache.synapse.commons.SynapseCommonsException;

    import javax.xml.namespace.QName;
    import java.lang.reflect.Method;

    /**
     * This class will be used as a Helper class to get the properties loaded while building the
     * Synapse Configuration from the XML
     */
    public class PropertyHelper {

        /**
         * Log variable for the logging purposes
         */
        private static final Log log = LogFactory.getLog(PropertyHelper.class);

        /**
         * Find and invoke the setter method with the name of form setXXX passing in the value given
         * on the POJO object
         *
         * @param name name of the setter field
         * @param val  value to be set
         * @param obj  POJO instance
         */
        public static void setInstanceProperty(String name, Object val, Object obj) {

            String mName = "set" + Character.toUpperCase(name.charAt(0)) + name.substring(1);
            Method method;

            try {
                Method[] methods = obj.getClass().getMethods();
                boolean invoked = false;

                for (Method method1 : methods) {
                    if (mName.equals(method1.getName())) {
                        Class[] params = method1.getParameterTypes();
                        if (params.length != 1) {
                            handleException("Did not find a setter method named : " + mName +
                                    "() that takes a single String, int, long, float, double ," +
                                    "OMElement or boolean parameter");
                        } else if (val instanceof String) {
                            String value = (String) val;
                            if (String.class.equals(params[0])) {
                                method = obj.getClass().getMethod(mName, String.class);
                                method.invoke(obj, new String[]{value});
                            } else if (int.class.equals(params[0])) {
                                method = obj.getClass().getMethod(mName, int.class);
                                method.invoke(obj, new Integer[]{new Integer(value)});
                            } else if (long.class.equals(params[0])) {
                                method = obj.getClass().getMethod(mName, long.class);
                                method.invoke(obj, new Long[]{new Long(value)});
                            } else if (float.class.equals(params[0])) {
                                method = obj.getClass().getMethod(mName, float.class);
                                method.invoke(obj, new Float[]{new Float(value)});
                            } else if (double.class.equals(params[0])) {
                                method = obj.getClass().getMethod(mName, double.class);
                                method.invoke(obj, new Double[]{new Double(value)});
                            } else if (boolean.class.equals(params[0])) {
                                method = obj.getClass().getMethod(mName, boolean.class);
                                method.invoke(obj, new Boolean[]{Boolean.valueOf(value)});
                            } else {
                                continue;
                            }
                        } else if (val instanceof OMElement && OMElement.class.equals(params[0])) {
                            method = obj.getClass().getMethod(mName, OMElement.class);
                            method.invoke(obj, new OMElement[]{(OMElement) val});
                        } else {
                            continue;
                        }
                        invoked = true;
                        break;
                    }
                }

                if (!invoked) {
                    handleException("Did not find a setter method named : " + mName +
                            "() that takes a single String, int, long, float, double " +
                            "or boolean parameter");
                }

            } catch (Exception e) {
                handleException("Error invoking setter method named : " + mName +
                        "() that takes a single String, int, long, float, double " +
                        "or boolean parameter", e);
            }
        }

        /**
         * This method will set the static property discribed in the OMElement to the specified object.
         * This Object should have the setter method for the specified property name
         *
         * @param property - OMElement specifying the property to be built in to the object
         * @param o        - Object to which the specified property will be set.
         */
        public static void setStaticProperty(OMElement property, Object o) {

            if (("property".equals(property.getLocalName().toLowerCase()))) {

                String propertyName = property.getAttributeValue(new QName("name"));
                String mName = "set"
                        + Character.toUpperCase(propertyName.charAt(0))
                        + propertyName.substring(1);

                // try to set String value first
                if (property.getAttributeValue(new QName("value")) != null) {
                    String value = property.getAttributeValue(new QName("value"));
                    setInstanceProperty(propertyName, value, o);
                } else {
                    // now try XML child
                    OMElement value = property.getFirstElement();
                    if (value != null) {

                        try {
                            Method method = o.getClass().getMethod(mName, OMElement.class);
                            if (log.isDebugEnabled()) {
                                log.debug("Setting property :: invoking method "
                                        + mName + "(" + value + ")");
                            }
                            method.invoke(o, value);

                        } catch (Exception e) {
                            handleException("Error setting property : " + propertyName
                                    + " as an OMElement property into class mediator : "
                                    + o.getClass() + " : " + e.getMessage(), e);
                        }

                    }

                }
            }
        }

        /**
         * This method will check the given OMElement represent either a static property or not
         *
         * @param property - OMElement to be checked for the static property
         * @return boolean true if the elemet represents a static property element false otherwise
         */
        public static boolean isStaticProperty(OMElement property) {
            return "property".equals(property.getLocalName().toLowerCase())
                    && (property.getAttributeValue(new QName("expression")) == null);
        }

        private static void handleException(String message, Throwable e) {
            log.error(message + e.getMessage());
            throw new SynapseCommonsException(message, e);
        }

        private static void handleException(String message) {
            log.error(message);
            throw new SynapseCommonsException(message);
        }
    }