/*
* This program is free software; you can redistribute it and/or modify it under the
* terms of the GNU Lesser General Public License, version 2.1 as published by the Free Software
* Foundation.
*
* You should have received a copy of the GNU Lesser General Public License along with this
* program; if not, you can obtain a copy at http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
* or from the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* This program 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.
*
* Copyright (c) 2001 - 2013 Object Refinery Ltd, Pentaho Corporation and Contributors.. All rights reserved.
*/
package org.pentaho.reporting.engine.classic.core.function;
import org.pentaho.reporting.engine.classic.core.event.ReportEvent;
/**
* Creates anchor objects for the current group. The anchors generated consist of the group's name and the current group
* count.
* <p/>
* To use the CreateGroupAnchorsFunction set the group's name as the function's group-property value. Next, add a
* AnchorElement to where the anchor should be generated (usually either the group-header or footer) and give the
* function's name as fieldname in the anchor-field.
*
* @author Thomas Morgner
* @deprecated It is easier to create anchors using a Style-expression. The Anchor-Field has been deprecated now.
*/
public class CreateGroupAnchorsFunction extends AbstractFunction {
/**
* The name of the group for which anchors should be created.
*/
private String group;
/**
* A prefix for the anchor name.
*/
private String anchorPrefix;
/**
* A temporary variable holding the last anchor created by this function.
*/
private String anchor;
/**
* A counter to create unique anchor names.
*/
private int count;
/**
* Default Constructor. Does nothing.
*/
public CreateGroupAnchorsFunction() {
anchorPrefix = "anchor";
}
/**
* Returns the prefix for the generated anchor.
*
* @return the anchor prefix.
*/
public String getAnchorPrefix() {
return anchorPrefix;
}
/**
* Defines the prefix for the generated anchor.
*
* @param anchorPrefix
* the prefix for the anchor.
*/
public void setAnchorPrefix( final String anchorPrefix ) {
if ( anchorPrefix == null ) {
throw new NullPointerException( "The Anchor-Prefix must not be null." );
}
this.anchorPrefix = anchorPrefix;
}
/**
* Returns the name of the group for which an anchor should be generated.
*
* @return the name of the group.
*/
public String getGroup() {
return group;
}
/**
* Defines the name of the group for which an anchor should be generated.
*
* @param group
* the name of the group.
*/
public void setGroup( final String group ) {
this.group = group;
}
/**
* Receives notification that report generation initializes the current run.
* <P>
* The event carries a ReportState.Started state. Use this to initialize the report.
*
* @param event
* The event.
*/
public void reportInitialized( final ReportEvent event ) {
count = 0;
final StringBuilder targetBuffer = new StringBuilder();
final String prefix = getAnchorPrefix();
targetBuffer.append( prefix );
targetBuffer.append( getGroup() );
targetBuffer.append( "%3D" );
targetBuffer.append( count );
anchor = targetBuffer.toString();
}
/**
* Receives notification that a group has started.
*
* @param event
* the event.
*/
public void groupStarted( final ReportEvent event ) {
if ( FunctionUtilities.isDefinedGroup( getGroup(), event ) == false ) {
return;
}
final StringBuilder targetBuffer = new StringBuilder();
final String prefix = getAnchorPrefix();
targetBuffer.append( prefix );
targetBuffer.append( getGroup() );
targetBuffer.append( "%3D" );
targetBuffer.append( count );
anchor = targetBuffer.toString();
}
/**
* Return the current expression value.
* <P>
* The value depends (obviously) on the expression implementation.
*
* @return the value of the function.
*/
public Object getValue() {
return anchor;
}
}