001 /**
002 * ========================================
003 * JFreeReport : a free Java report library
004 * ========================================
005 *
006 * Project Info: http://reporting.pentaho.org/
007 *
008 * (C) Copyright 2000-2007, by Object Refinery Limited, Pentaho Corporation and Contributors.
009 *
010 * This library is free software; you can redistribute it and/or modify it under the terms
011 * of the GNU Lesser General Public License as published by the Free Software Foundation;
012 * either version 2.1 of the License, or (at your option) any later version.
013 *
014 * This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
015 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
016 * See the GNU Lesser General Public License for more details.
017 *
018 * You should have received a copy of the GNU Lesser General Public License along with this
019 * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
020 * Boston, MA 02111-1307, USA.
021 *
022 * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
023 * in the United States and other countries.]
024 *
025 * ------------
026 * $Id: AbstractLayoutController.java,v 1.2 2007/04/01 18:49:25 taqua Exp $
027 * ------------
028 * (C) Copyright 2000-2005, by Object Refinery Limited.
029 * (C) Copyright 2005-2007, by Pentaho Corporation.
030 */
031
032 package org.jfree.report.flow.layoutprocessor;
033
034 import org.jfree.report.flow.FlowController;
035 import org.jfree.report.DataSourceException;
036 import org.jfree.report.ReportDataFactoryException;
037 import org.jfree.report.ReportProcessingException;
038 import org.jfree.util.Log;
039
040 /**
041 * Todo: Document me!
042 *
043 * @author Thomas Morgner
044 * @since 05.03.2007
045 */
046 public abstract class AbstractLayoutController implements LayoutController
047 {
048 private FlowController flowController;
049 private LayoutController parent;
050 private Object node;
051 private boolean initialized;
052
053 protected AbstractLayoutController()
054 {
055 }
056
057 /**
058 * Retrieves the parent of this layout controller. This allows childs to query
059 * their context.
060 *
061 * @return the layout controller's parent to <code>null</code> if there is no
062 * parent.
063 */
064 public LayoutController getParent()
065 {
066 return parent;
067 }
068
069
070 /**
071 * Initializes the layout controller. This method is called exactly once. It
072 * is the creators responsibility to call this method.
073 * <p/>
074 * Calling initialize after the first advance must result in a
075 * IllegalStateException.
076 *
077 * @param node the currently processed object or layout node.
078 * @param flowController the current flow controller.
079 * @param parent the parent layout controller that was responsible for
080 * instantiating this controller.
081 * @throws DataSourceException if there was a problem reading data from
082 * the datasource.
083 * @throws ReportProcessingException if there was a general problem during
084 * the report processing.
085 * @throws ReportDataFactoryException if a query failed.
086 */
087 public void initialize(final Object node, final FlowController flowController,
088 final LayoutController parent)
089 throws DataSourceException, ReportDataFactoryException,
090 ReportProcessingException
091 {
092 if (initialized == true)
093 {
094 throw new IllegalStateException();
095 }
096
097 this.initialized = true;
098 this.node = node;
099 this.flowController = flowController;
100 this.parent = parent;
101 }
102
103 public Object clone()
104 {
105 try
106 {
107 return super.clone();
108 }
109 catch (CloneNotSupportedException e)
110 {
111 Log.error ("Clone failed where it shouldn't.", e);
112 throw new IllegalStateException("Clone failed?");
113 }
114 }
115
116
117 public FlowController getFlowController()
118 {
119 return flowController;
120 }
121
122
123 public Object getNode()
124 {
125 return node;
126 }
127
128
129 public boolean isInitialized()
130 {
131 return initialized;
132 }
133
134 /**
135 * Derives a copy of this controller that is suitable to perform a
136 * precomputation.
137 *
138 * @param fc
139 * @return
140 */
141 public LayoutController createPrecomputeInstance(FlowController fc)
142 {
143 final AbstractLayoutController lc = (AbstractLayoutController) clone();
144 lc.flowController = fc;
145 return lc;
146 }
147 }