/* ===========================================================
 
* JFreeChart : a free chart library for the Java(tm) platform
 
* ===========================================================
 
*
 
* (C) Copyright 2000-2016, by Object Refinery Limited and Contributors.
 
*
 
* Project Info:
  
http://www.jfree.org/jfreechart/index.html
 
*
 
* This library is free software; you can redistribute it and/or modify it
 
* under the terms of the GNU Lesser General Public License as published by
 
* the Free Software Foundation; either version 2.1 of the License, or
 
* (at your option) any later version.
 
*
 
* This library 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.
 
*
 
* You should have received a copy of the GNU Lesser General Public
 
* License along with this library; if not, write to the Free Software
 
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  
02110-1301,
 
* USA.
 
*
 
* [Oracle and Java are registered trademarks of Oracle and/or its affiliates.
 
* Other names may be trademarks of their respective owners.]
 
*
 
* -----------------------------
 
* PieSectionLabelGenerator.java
 
* -----------------------------
 
* (C) Copyright 2001-2008, by Object Refinery Limited.
 
*
 
* Original Author:
  
David Gilbert (for Object Refinery Limited);
 
* Contributor(s):
   
-;
 
*
 
* Changes
 
* -------
 
* 13-Dec-2001 : Version 1 (DG);
 
* 16-Jan-2002 : Completed Javadocs (DG);
 
* 26-Sep-2002 : Fixed errors reported by Checkstyle (DG);
 
* 30-Oct-2002 : Category is now a Comparable instance (DG);
 
* 07-Mar-2003 : Changed to KeyedValuesDataset and added pieIndex
 
*
               
parameter (DG);
 
* 21-Mar-2003 : Updated Javadocs (DG);
 
* 24-Apr-2003 : Switched around PieDataset and KeyedValuesDataset (DG);
 
* 13-Aug-2003 : Added clone() method (DG);
 
* 19-Aug-2003 : Renamed PieToolTipGenerator --> PieItemLabelGenerator (DG);
 
* 11-Nov-2003 : Removed clone() method (DG);
 
* 30-Jan-2004 : Added generateSectionLabel() method (DG);
 
* 15-Apr-2004 : Moved generateToolTip() method into separate interface and
 
*
               
renamed this interface PieSectionLabelGenerator (DG);
 
*
 
*/

package org.jfree.chart.labels;

import java.awt.Font;
import java.awt.Paint;
import java.awt.font.TextAttribute;
import java.text.AttributedString;

import org.jfree.data.general.PieDataset;

/**
 
* Interface for a label generator for plots that use data from
 
* a {@link PieDataset}.
 
*/

public interface PieSectionLabelGenerator {

    
/**
     
* Generates a label for a pie section.
     
*
     
* @param dataset
  
the dataset ({@code null} not permitted).
     
* @param key
  
the section key ({@code null} not permitted).
     
*
     
* @return The label (possibly {@code null}).
     
*/

    
public String generateSectionLabel(PieDataset dataset, Comparable key);

    
/**
     
* Generates an attributed label for the specified series, or
     
* {@code null} if no attributed label is available (in which case,
     
* the string returned by
     
* {@link #generateSectionLabel(PieDataset, Comparable)} will
     
* provide the fallback).
  
Only certain attributes are recognised by the
     
* code that ultimately displays the labels:
     
* <ul>
     
* <li>{@link TextAttribute#FONT}: will set the font;</li>
     
* <li>{@link TextAttribute#POSTURE}: a value of
     
*{@link TextAttribute#POSTURE_OBLIQUE} will add {@link Font#ITALIC} to
     
*the current font;</li>
     
* <li>{@link TextAttribute#WEIGHT}: a value of
     
*{@link TextAttribute#WEIGHT_BOLD} will add {@link Font#BOLD} to the
     
*current font;</li>
     
* <li>{@link TextAttribute#FOREGROUND}: this will set the {@link Paint}
     
*for the current</li>
     
* <li>{@link TextAttribute#SUPERSCRIPT}: the values
     
*{@link TextAttribute#SUPERSCRIPT_SUB} and
     
*{@link TextAttribute#SUPERSCRIPT_SUPER} are recognised.</li>
     
* </ul>
     
*
     
* @param dataset
  
the dataset.
     
* @param key
  
the key.
     
*
     
* @return An attributed label (possibly {@code null}).
     
*/

    
public AttributedString generateAttributedSectionLabel(PieDataset dataset,
                                                           
Comparable key);

}