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: * ClassLoaderObjectDescription.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: ClassLoaderObjectDescription.java,v 1.5 2005/11/14 11:01:04 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.lang.reflect.Constructor;
047: import java.lang.reflect.Modifier;
048:
049: import org.jfree.util.ObjectUtilities;
050:
051: /**
052: * An object-description for a class loader.
053: *
054: * @author Thomas Morgner
055: */
056: public class ClassLoaderObjectDescription extends
057: AbstractObjectDescription {
058:
059: /**
060: * Creates a new object description.
061: */
062: public ClassLoaderObjectDescription() {
063: super (Object.class);
064: setParameterDefinition("class", String.class);
065: }
066:
067: /**
068: * Creates an object based on this object description.
069: *
070: * @return The object.
071: */
072: public Object createObject() {
073: try {
074: final String o = (String) getParameter("class");
075: return ObjectUtilities.getClassLoader(getClass())
076: .loadClass(o).newInstance();
077: } catch (Exception e) {
078: return null;
079: }
080: }
081:
082: /**
083: * Sets the parameters of the object description to match the supplied object.
084: *
085: * @param o the object.
086: *
087: * @throws ObjectFactoryException if there is a problem while reading the
088: * properties of the given object.
089: */
090: public void setParameterFromObject(final Object o)
091: throws ObjectFactoryException {
092: if (o == null) {
093: throw new ObjectFactoryException("The Object is null.");
094: }
095: try {
096: final Constructor c = o.getClass().getConstructor(
097: new Class[0]);
098: if (!Modifier.isPublic(c.getModifiers())) {
099: throw new ObjectFactoryException(
100: "The given object has no public default constructor. ["
101: + o.getClass() + "]");
102: }
103: setParameter("class", o.getClass().getName());
104: } catch (Exception e) {
105: throw new ObjectFactoryException(
106: "The given object has no default constructor. ["
107: + o.getClass() + "]", e);
108: }
109: }
110: }
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