Overrides behavior on Apache commons-configuration so that the property-file include mechanism "overwrites" older values

OverridablePropertiesConfiguration.java

package com.technofovea.springtest;

import java.io.File;
import java.lang.reflect.Array;
import java.net.URL;
import java.util.Collection;
import java.util.Iterator;
import org.apache.commons.configuration.Configuration;
import org.apache.commons.configuration.ConfigurationException;
import org.apache.commons.configuration.PropertiesConfiguration;

/**
 * Functions just like PropertiesConfiguration, except that when trying 
 * to retrieve a scalar value from an array or collection, the *last* element is
 * produced instead of the first.
 * 
 * This means that later attempts to set a property will override earlier uses,
 * instead of being hidden.
 * 
 * @author Darien Hager
 */
public class OverridablePropertiesConfiguration extends PropertiesConfiguration implements Configuration{
    public OverridablePropertiesConfiguration(URL url) throws ConfigurationException {
        super(url);
    }

    public OverridablePropertiesConfiguration(File file) throws ConfigurationException {
        super(file);
    }

    public OverridablePropertiesConfiguration(String fileName) throws ConfigurationException {
        super(fileName);
    }

    public OverridablePropertiesConfiguration() {
        super();
    }
    
    @Override
    protected Object resolveContainerStore(String key)
    {
        Object value = getProperty(key);
        if (value != null)
        {
            if (value instanceof Collection)
            {
                Collection collection = (Collection) value;
                Iterator i = collection.iterator();
                value = null;
                while(i.hasNext()){
                    // Leave with *last* value or null
                    value = i.next();
                }
            }
            else if (value.getClass().isArray() && Array.getLength(value) > 0)
            {
                // Pull back *last* value
                value = Array.get(value, Array.getLength(value)-1);
            }
        }

        return value;
    }  
}