content: /* ========================================================================
   * JCommon : a free general purpose class library for the Java(tm) platform
   * ========================================================================
   *
   * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
   *
   * Project Info:  http://www.jfree.org/jcommon/index.html
   *
   * This library is free software; you can redistribute it and/or modify it
   * under the terms of the GNU Lesser General Public License as published by
   * the Free Software Foundation; either version 2.1 of the License, or
   * (at your option) any later version.
   *
   * This library is distributed in the hope that it will be useful, but
   * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
   * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
   * License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with this library; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
   * USA.
   *
   * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
   * in the United States and other countries.]
   *
   * ---------------------------------
   * ExtendedConfigurationWrapper.java
   * ---------------------------------
   * (C)opyright 2002-2005, by Thomas Morgner and Contributors.
   *
   * Original Author:  Thomas Morgner;
   * Contributor(s):   David Gilbert (for Object Refinery Limited);
   *
   * $Id: ExtendedConfigurationWrapper.java,v 1.8 2008/09/10 09:22:04 mungady Exp $
   *
   * Changes
   * -------
   * 20-May-2005 : Initial version.
   */
  
  package org.jfree.util;
  
  import java.util.Enumeration;
  import java.util.Iterator;
  
  /**
   * A wrapper for the extended configuration interface around a plain configuration.
   *
   * @author Thomas Morgner
   */
  public class ExtendedConfigurationWrapper
          implements ExtendedConfiguration
  {
    /** The base configuration. */
    private Configuration parent;
  
    /**
     * Creates a wrapper around the given configuration.
     *
     * @param parent the wrapped up configuration.
     * @throws NullPointerException if the parent is null.
     */
    public ExtendedConfigurationWrapper (final Configuration parent)
    {
      if (parent == null)
      {
        throw new NullPointerException("Parent given must not be null");
      }
      this.parent = parent;
    }
  
    /**
     * Returns the boolean value of a given configuration property. The boolean value true
     * is returned, if the contained string is equal to 'true'.
     *
     * @param name the name of the property
     * @return the boolean value of the property.
     */
    public boolean getBoolProperty (final String name)
    {
      return getBoolProperty(name, false);
    }
  
    /**
     * Returns the boolean value of a given configuration property. The boolean value true
     * is returned, if the contained string is equal to 'true'. If the property is not set,
     * the default value is returned.
     *
     * @param name the name of the property
     * @param defaultValue the default value to be returned if the property is not set
     * @return the boolean value of the property.
     */
    public boolean getBoolProperty (final String name,
                                    final boolean defaultValue)
    {
      return "true".equals(this.parent.getConfigProperty(name, String.valueOf(defaultValue)));
    }
  
    /**
     * Returns a given property as int value. Zero is returned if the
     * property value is no number or the property is not set.
     *
     * @param name the name of the property
     * @return the parsed number value or zero
     */
    public int getIntProperty (final String name)
    {
      return getIntProperty(name, 0);
    }
  
    /**
     * Returns a given property as int value. The specified default value is returned if the
     * property value is no number or the property is not set.
     *
     * @param name the name of the property
     * @param defaultValue the value to be returned if the property is no integer value
     * @return the parsed number value or the specified default value
     */
    public int getIntProperty (final String name,
                               final int defaultValue)
    {
      final String retval = this.parent.getConfigProperty(name);
      if (retval == null)
      {
        return defaultValue;
      }
      try
      {
        return Integer.parseInt(retval);
      }
      catch (Exception e)
      {
        return defaultValue;
      }
    }
  
    /**
     * Checks, whether a given property is defined.
     *
     * @param name the name of the property
     * @return true, if the property is defined, false otherwise.
     */
    public boolean isPropertySet (final String name)
    {
      return this.parent.getConfigProperty(name) != null;
    }
  
    /**
     * Returns all keys with the given prefix.
     *
     * @param prefix the prefix
     * @return the iterator containing all keys with that prefix
     */
    public Iterator findPropertyKeys (final String prefix)
    {
      return this.parent.findPropertyKeys(prefix);
    }
  
    /**
     * Returns the configuration property with the specified key.
     *
     * @param key the property key.
     * @return the property value.
     */
    public String getConfigProperty (final String key)
    {
      return this.parent.getConfigProperty(key);
    }
  
    /**
     * Returns the configuration property with the specified key (or the specified default
     * value if there is no such property).
     * <p/>
     * If the property is not defined in this configuration, the code will lookup the
     * property in the parent configuration.
     *
     * @param key          the property key.
     * @param defaultValue the default value.
     * @return the property value.
     */
    public String getConfigProperty (final String key, final String defaultValue)
    {
      return this.parent.getConfigProperty(key, defaultValue);
    }
  
    /**
     * Returns an enumeration of the configuration properties.
     *
     * @return An enumeration.
     */
    public Enumeration getConfigProperties()
    {
      return this.parent.getConfigProperties();
    }
  
    /**
     * Returns a clone of this instance.
     *
     * @return A clone.
     *
     * @throws CloneNotSupportedException if there is a problem cloning.
     */
    public Object clone () throws CloneNotSupportedException
    {
      ExtendedConfigurationWrapper wrapper = (ExtendedConfigurationWrapper) super.clone();
      wrapper.parent = (Configuration) this.parent.clone();
      return this.parent;
    }
  }
  