/***************************************
 *                                     *
 *  JBoss: The OpenSource J2EE WebOS   *
 *                                     *
 *  Distributable under LGPL license.  *
 *  See terms of license at gnu.org.   *
 *                                     *
 ***************************************/

package org.jboss.util.propertyeditor;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.util.Iterator;
import java.util.Properties;

import org.jboss.util.NestedRuntimeException;
import org.jboss.util.StringPropertyReplacer;

/**
 * A property editor for {@link java.util.Properties}.
 *
 * @author Jason Dillon
 * @author Scott.Stark@jboss.org
 * @version $Revision: 1.1.4.2 $
 */
public class PropertiesEditor
   extends TextPropertyEditorSupport
{
   /**
    * Returns a Properties object initialized with current getAsText value
    * interpretted as a .properties file contents. This replaces any
    * references of the form ${x} with the corresponding system property. 
    *
    * @return a Properties object
    *
    * @throws NestedRuntimeException  An IOException occured.
    */
   public Object getValue()
   {
      try
      {
         // Load the current key=value properties into a Properties object
         String propsText = getAsText();
         Properties rawProps = new Properties(System.getProperties());
         ByteArrayInputStream bais = new ByteArrayInputStream(propsText.getBytes());
         rawProps.load(bais);
         // Now go through the rawProps and replace any ${x} refs
         Properties props = new Properties();
         Iterator keys = rawProps.keySet().iterator();
         while( keys.hasNext() )
         {
            String key = (String) keys.next();
            String value = rawProps.getProperty(key);
            String value2 = StringPropertyReplacer.replaceProperties(value, rawProps);
            props.setProperty(key, value2);
         }
         rawProps.clear();

         return props;
      }
      catch (IOException e)
      {
         throw new NestedRuntimeException(e);
      }
   }

}
