org.springframework.extensions.config.xml.elementreader.GenericElementReader.java Source code

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Here is the source code for org.springframework.extensions.config.xml.elementreader.GenericElementReader.java

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/**
 * Copyright (C) 2005-2009 Alfresco Software Limited.
 *
 * This file is part of the Spring Surf Extension project.
 *
 * Licensed 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.springframework.extensions.config.xml.elementreader;

import java.util.Iterator;

import org.dom4j.Attribute;
import org.dom4j.Element;
import org.springframework.extensions.config.ConfigElement;
import org.springframework.extensions.config.element.GenericConfigElement;
import org.springframework.extensions.config.xml.XMLConfigService.PropertyConfigurer;

/**
 * Implementation of a generic element reader. This class can be used to 
 * convert any config element into a GenericConfigElement.
 * 
 * @author gavinc
 */
public class GenericElementReader implements ConfigElementReader {
    private PropertyConfigurer propertyConfigurer;

    /**
     * Construct
     * 
     * @param propertyConfigurer
     */
    public GenericElementReader(PropertyConfigurer propertyConfigurer) {
        this.propertyConfigurer = propertyConfigurer;
    }

    /**
     * @see org.springframework.extensions.config.xml.elementreader.ConfigElementReader#parse(org.dom4j.Element)
     */
    public ConfigElement parse(Element element) {
        GenericConfigElement configElement = null;

        if (element != null) {
            configElement = createConfigElement(element);

            // process any children there may be
            processChildren(element, configElement);
        }

        return configElement;
    }

    /**
     * Recursively processes the children creating the required config element
     * objects as it goes
     * 
     * @param element
     * @param parentConfig
     */
    @SuppressWarnings("unchecked")
    protected void processChildren(Element element, GenericConfigElement parentConfig) {
        // get the list of children for the given element
        Iterator<Element> children = element.elementIterator();
        while (children.hasNext()) {
            Element child = children.next();
            GenericConfigElement childConfigElement = createConfigElement(child);
            parentConfig.addChild(childConfigElement);

            // recurse down the children
            processChildren(child, childConfigElement);
        }
    }

    /**
     * Creates a ConfigElementImpl object from the given element.
     * 
     * @param element The element to parse
     * @return The GenericConfigElement representation of the given element
     */
    @SuppressWarnings("unchecked")
    protected GenericConfigElement createConfigElement(Element element) {
        // get the name and value of the given element
        String name = element.getName();

        // create the config element object and populate with value
        // and attributes
        GenericConfigElement configElement = new GenericConfigElement(name);
        if ((element.hasContent()) && (element.hasMixedContent() == false)) {
            String value = element.getTextTrim();
            if (value != null && value.length() > 0) {
                if (propertyConfigurer != null) {
                    value = propertyConfigurer.resolveValue(value);
                }
                configElement.setValue(value);
            }
        }

        Iterator<Attribute> attrs = element.attributeIterator();
        while (attrs.hasNext()) {
            Attribute attr = attrs.next();
            String attrName = attr.getName();
            String attrValue = attr.getValue();

            if (propertyConfigurer != null) {
                attrValue = propertyConfigurer.resolveValue(attrValue);
            }

            configElement.addAttribute(attrName, attrValue);
        }

        return configElement;
    }
}