    001    /* ========================================================================
    002     * JCommon : a free general purpose class library for the Java(tm) platform
    003     * ========================================================================
    004     *
    005     * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
    006     *
    007     * Project Info:  http://www.jfree.org/jcommon/index.html
    008     *
    009     * This library is free software; you can redistribute it and/or modify it
    010     * under the terms of the GNU Lesser General Public License as published by
    011     * the Free Software Foundation; either version 2.1 of the License, or
    012     * (at your option) any later version.
    013     *
    014     * This library is distributed in the hope that it will be useful, but
    015     * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
    016     * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
    017     * License for more details.
    018     *
    019     * You should have received a copy of the GNU Lesser General Public
    020     * License along with this library; if not, write to the Free Software
    021     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
    022     * USA.
    023     *
    024     * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
    025     * in the United States and other countries.]
    026     *
    027     * ---------------------------------
    028     * ExtendedConfigurationWrapper.java
    029     * ---------------------------------
    030     * (C)opyright 2002-2005, by Thomas Morgner and Contributors.
    031     *
    032     * Original Author:  Thomas Morgner;
    033     * Contributor(s):   David Gilbert (for Object Refinery Limited);
    034     *
    035     * $Id: ExtendedConfigurationWrapper.java,v 1.8 2008/09/10 09:22:04 mungady Exp $
    036     *
    037     * Changes
    038     * -------
    039     * 20-May-2005 : Initial version.
    040     */
    041
    042    package org.jfree.util;
    043
    044    import java.util.Enumeration;
    045    import java.util.Iterator;
    046
    047    /**
    048     * A wrapper for the extended configuration interface around a plain configuration.
    049     *
    050     * @author Thomas Morgner
    051     */
    052    public class ExtendedConfigurationWrapper
    053            implements ExtendedConfiguration
    054    {
    055      /** The base configuration. */
    056      private Configuration parent;
    057
    058      /**
    059       * Creates a wrapper around the given configuration.
    060       *
    061       * @param parent the wrapped up configuration.
    062       * @throws NullPointerException if the parent is null.
    063       */
    064      public ExtendedConfigurationWrapper (final Configuration parent)
    065      {
    066        if (parent == null)
    067        {
    068          throw new NullPointerException("Parent given must not be null");
    069        }
    070        this.parent = parent;
    071      }
    072
    073      /**
    074       * Returns the boolean value of a given configuration property. The boolean value true
    075       * is returned, if the contained string is equal to 'true'.
    076       *
    077       * @param name the name of the property
    078       * @return the boolean value of the property.
    079       */
    080      public boolean getBoolProperty (final String name)
    081      {
    082        return getBoolProperty(name, false);
    083      }
    084
    085      /**
    086       * Returns the boolean value of a given configuration property. The boolean value true
    087       * is returned, if the contained string is equal to 'true'. If the property is not set,
    088       * the default value is returned.
    089       *
    090       * @param name the name of the property
    091       * @param defaultValue the default value to be returned if the property is not set
    092       * @return the boolean value of the property.
    093       */
    094      public boolean getBoolProperty (final String name,
    095                                      final boolean defaultValue)
    096      {
    097        return "true".equals(this.parent.getConfigProperty(name, String.valueOf(defaultValue)));
    098      }
    099
    100      /**
    101       * Returns a given property as int value. Zero is returned if the
    102       * property value is no number or the property is not set.
    103       *
    104       * @param name the name of the property
    105       * @return the parsed number value or zero
    106       */
    107      public int getIntProperty (final String name)
    108      {
    109        return getIntProperty(name, 0);
    110      }
    111
    112      /**
    113       * Returns a given property as int value. The specified default value is returned if the
    114       * property value is no number or the property is not set.
    115       *
    116       * @param name the name of the property
    117       * @param defaultValue the value to be returned if the property is no integer value
    118       * @return the parsed number value or the specified default value
    119       */
    120      public int getIntProperty (final String name,
    121                                 final int defaultValue)
    122      {
    123        final String retval = this.parent.getConfigProperty(name);
    124        if (retval == null)
    125        {
    126          return defaultValue;
    127        }
    128        try
    129        {
    130          return Integer.parseInt(retval);
    131        }
    132        catch (Exception e)
    133        {
    134          return defaultValue;
    135        }
    136      }
    137
    138      /**
    139       * Checks, whether a given property is defined.
    140       *
    141       * @param name the name of the property
    142       * @return true, if the property is defined, false otherwise.
    143       */
    144      public boolean isPropertySet (final String name)
    145      {
    146        return this.parent.getConfigProperty(name) != null;
    147      }
    148
    149      /**
    150       * Returns all keys with the given prefix.
    151       *
    152       * @param prefix the prefix
    153       * @return the iterator containing all keys with that prefix
    154       */
    155      public Iterator findPropertyKeys (final String prefix)
    156      {
    157        return this.parent.findPropertyKeys(prefix);
    158      }
    159
    160      /**
    161       * Returns the configuration property with the specified key.
    162       *
    163       * @param key the property key.
    164       * @return the property value.
    165       */
    166      public String getConfigProperty (final String key)
    167      {
    168        return this.parent.getConfigProperty(key);
    169      }
    170
    171      /**
    172       * Returns the configuration property with the specified key (or the specified default
    173       * value if there is no such property).
    174       * <p/>
    175       * If the property is not defined in this configuration, the code will lookup the
    176       * property in the parent configuration.
    177       *
    178       * @param key          the property key.
    179       * @param defaultValue the default value.
    180       * @return the property value.
    181       */
    182      public String getConfigProperty (final String key, final String defaultValue)
    183      {
    184        return this.parent.getConfigProperty(key, defaultValue);
    185      }
    186
    187      /**
    188       * Returns an enumeration of the configuration properties.
    189       *
    190       * @return An enumeration.
    191       */
    192      public Enumeration getConfigProperties()
    193      {
    194        return this.parent.getConfigProperties();
    195      }
    196
    197      /**
    198       * Returns a clone of this instance.
    199       *
    200       * @return A clone.
    201       *
    202       * @throws CloneNotSupportedException if there is a problem cloning.
    203       */
    204      public Object clone () throws CloneNotSupportedException
    205      {
    206        ExtendedConfigurationWrapper wrapper = (ExtendedConfigurationWrapper) super.clone();
    207        wrapper.parent = (Configuration) this.parent.clone();
    208        return this.parent;
    209      }
    210    }