    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     * ObjectDescription.java
    029     * ----------------------
    030     * (C)opyright 2003, 2004, by Thomas Morgner and Contributors.
    031     *
    032     * Original Author:  Thomas Morgner;
    033     * Contributor(s):   David Gilbert (for Object Refinery Limited);
    034     *
    035     * $Id: ObjectDescription.java,v 1.3 2005/11/14 11:03:12 mungady Exp $
    036     *
    037     * Changes (from 19-Feb-2003)
    038     * -------------------------
    039     * 19-Feb-2003 : Added standard header and Javadocs (DG);
    040     * 29-Apr-2003 : Distilled from the JFreeReport project and moved into JCommon
    041     *
    042     */
    043
    044    package org.jfree.xml.factory.objects;
    045
    046    import java.io.Serializable;
    047    import java.util.Iterator;
    048
    049    import org.jfree.util.Configuration;
    050
    051    /**
    052     * An interface for object descriptions.
    053     *
    054     * @author Thomas Morgner
    055     */
    056    public interface ObjectDescription extends Serializable {
    057
    058        /**
    059         * Returns a parameter definition. If the parameter is invalid, this
    060         * function returns null.
    061         *
    062         * @param name  the definition name.
    063         *
    064         * @return The parameter class or null, if the parameter is not defined.
    065         */
    066        public Class getParameterDefinition(String name);
    067
    068        /**
    069         * Sets the value of a parameter.
    070         *
    071         * @param name  the parameter name.
    072         * @param value  the parameter value.
    073         */
    074        public void setParameter(String name, Object value);
    075
    076        /**
    077         * Returns the value of a parameter.
    078         *
    079         * @param name  the parameter name.
    080         *
    081         * @return The value.
    082         */
    083        public Object getParameter(String name);
    084
    085        /**
    086         * Returns an iterator the provides access to the parameter names. This
    087         * returns all _known_ parameter names, the object description may accept
    088         * additional parameters.
    089         *
    090         * @return The iterator.
    091         */
    092        public Iterator getParameterNames();
    093
    094        /**
    095         * Returns the object class.
    096         *
    097         * @return The Class.
    098         */
    099        public Class getObjectClass();
    100
    101        /**
    102         * Creates an object based on the description.
    103         *
    104         * @return The object.
    105         */
    106        public Object createObject();
    107
    108        /**
    109         * Returns a cloned instance of the object description. The contents
    110         * of the parameter objects collection are cloned too, so that any
    111         * already defined parameter value is copied to the new instance.
    112         * <p>
    113         * Parameter definitions are not cloned, as they are considered read-only.
    114         * <p>
    115         * The newly instantiated object description is not configured. If it
    116         * need to be configured, then you have to call configure on it.
    117         *
    118         * @return A cloned instance.
    119         */
    120        public ObjectDescription getUnconfiguredInstance();
    121
    122        /**
    123         * Returns a cloned instance of the object description. The contents
    124         * of the parameter objects collection are cloned too, so that any
    125         * already defined parameter value is copied to the new instance.
    126         * <p>
    127         * Parameter definitions are not cloned, as they are considered read-only.
    128         *
    129         * @return A cloned instance.
    130         */
    131        public ObjectDescription getInstance();
    132
    133        /**
    134         * Sets the parameters of this description object to match the supplied object.
    135         *
    136         * @param o  the object.
    137         *
    138         * @throws ObjectFactoryException if there is a problem while reading the
    139         * properties of the given object.
    140         */
    141        public void setParameterFromObject(Object o) throws ObjectFactoryException;
    142
    143
    144        /**
    145         * Configures this factory. The configuration contains several keys and
    146         * their defined values. The given reference to the configuration object
    147         * will remain valid until the report parsing or writing ends.
    148         * <p>
    149         * The configuration contents may change during the reporting.
    150         *
    151         * @param config the configuration, never null
    152         */
    153        public void configure(Configuration config);
    154
    155        /**
    156         * Compares whether two object descriptions are equal.
    157         *
    158         * @param o the other object.
    159         * @return true, if both object desciptions describe the same object, false otherwise.
    160         */
    161        public boolean equals (Object o);
    162
    163
    164        /**
    165         * Computes the hashCode for this ClassFactory. As equals() must be implemented,
    166         * a corresponding hashCode() should be implemented as well.
    167         *
    168         * @return the hashcode.
    169         */
    170        public int hashCode();
    171
    172    }