categoryaxis.java

大家打开看看啊, 很有用的东西

/* ======================================
 * JFreeChart : a free Java chart library
 * ======================================
 *
 * Project Info:  http://www.jfree.org/jfreechart/index.html
 * Project Lead:  David Gilbert ([e-mail]);
 *
 * (C) Copyright 2000-2003, by Object Refinery Limited and Contributors.
 *
 * 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., 59 Temple Place, Suite 330,
 * Boston, MA 02111-1307, USA.
 *
 * -----------------
 * CategoryAxis.java
 * -----------------
 * (C) Copyright 2000-2003, by Object Refinery Limited.
 *
 * Original Author:  David Gilbert;
 * Contributor(s):   -;
 *
 * $Id: CategoryAxis.java,v 1.10 2003/07/24 10:49:14 mungady Exp $
 *
 * Changes (from 21-Aug-2001)
 * --------------------------
 * 21-Aug-2001 : Added standard header. Fixed DOS encoding problem (DG);
 * 18-Sep-2001 : Updated header (DG);
 * 04-Dec-2001 : Changed constructors to protected, and tidied up default values (DG);
 * 19-Apr-2002 : Updated import statements (DG);
 * 05-Sep-2002 : Updated constructor for changes in Axis class (DG);
 * 06-Nov-2002 : Moved margins from the CategoryPlot class (DG);
 * 08-Nov-2002 : Moved to new package com.jrefinery.chart.axis (DG);
 * 22-Jan-2002 : Removed monolithic constructor (DG);
 * 26-Mar-2003 : Implemented Serializable (DG);
 * 09-May-2003 : Merged HorizontalCategoryAxis and VerticalCategoryAxis into this class (DG);
 *
 */

package org.jfree.chart.axis;

import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.Insets;
import java.awt.font.FontRenderContext;
import java.awt.font.LineBreakMeasurer;
import java.awt.font.LineMetrics;
import java.awt.font.TextLayout;
import java.awt.geom.AffineTransform;
import java.awt.geom.Rectangle2D;
import java.io.Serializable;
import java.text.AttributedCharacterIterator;
import java.text.AttributedString;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.jfree.chart.event.AxisChangeEvent;
import org.jfree.chart.plot.CategoryPlot;
import org.jfree.chart.plot.Plot;
import org.jfree.ui.RectangleEdge;
import org.jfree.ui.RefineryUtilities;

/**
 * The base class for axes that display categories.
 *
 * @author David Gilbert
 */
public class CategoryAxis extends Axis implements Serializable {

    /** The default setting for rotated category labels. */
    public static final boolean DEFAULT_VERTICAL_CATEGORY_LABELS = false;

    /** The default margin for the axis (used for both lower and upper margins). */
    public static final double DEFAULT_AXIS_MARGIN = 0.05;

    /** The default margin between categories (a percentage of the overall axis length). */
    public static final double DEFAULT_CATEGORY_MARGIN = 0.20;

    /** The amount of space reserved at the start of the axis. */
    private double lowerMargin;

    /** The amount of space reserved at the end of the axis. */
    private double upperMargin;

    /** The amount of space reserved between categories. */
    private double categoryMargin;

    /** A flag that indicates whether the category labels should be rotated 90 degrees. */
    private boolean verticalCategoryLabels;  // need to replace this with rotation, so that it fits
                                             // with both horizontal and vertical axes

    /** A flag that controls whether to skip category labels to avoid overlapping. */
    private boolean skipCategoryLabelsToFit;

    /** Tick line count */
    private int maxTickLineCount;

    /** Temporary list of categories. */
    private List categories;
    
    /** A temporary record of the amount of space reserved for the tick labels. */
    protected double reservedForTickLabels;
    
    /** A temporary record of the amount of space reserved for the axis label. */
    protected double reservedForAxisLabel;
    
    /**
     * Constructs a category axis, using default values where necessary.
     *
     * @param label  the axis label (<code>null</code> permitted).
     */
    public CategoryAxis(String label) {

        super(label);

        this.lowerMargin = DEFAULT_AXIS_MARGIN;
        this.upperMargin = DEFAULT_AXIS_MARGIN;
        this.categoryMargin = DEFAULT_CATEGORY_MARGIN;
        this.verticalCategoryLabels = DEFAULT_VERTICAL_CATEGORY_LABELS;
        this.setTickMarksVisible(false);  // not supported by this axis type yet
        this.categories = new java.util.ArrayList();
        
        this.reservedForAxisLabel = 0.0;
        this.reservedForTickLabels = 0.0;

    }

    /**
     * Returns the lower margin for the axis.
     *
     * @return the margin.
     */
    public double getLowerMargin() {
        return this.lowerMargin;
    }

    /**
     * Sets the lower margin for the axis.  An {@link AxisChangeEvent} is sent to all registered
     * listeners.
     *
     * @param margin  the new margin.
     */
    public void setLowerMargin(double margin) {
        this.lowerMargin = margin;
        notifyListeners(new AxisChangeEvent(this));
    }

    /**
     * Returns the upper margin for the axis.
     *
     * @return the margin.
     */
    public double getUpperMargin() {
        return this.upperMargin;
    }

    /**
     * Sets the upper margin for the axis.  An {@link AxisChangeEvent} is sent to all registered
     * listeners.
     *
     * @param margin  the new margin.
     */
    public void setUpperMargin(double margin) {
        this.upperMargin = margin;
        notifyListeners(new AxisChangeEvent(this));
    }

    /**
     * Returns the category margin.
     *
     * @return the margin.
     */
    public double getCategoryMargin() {
        return this.categoryMargin;
    }

    /**
     * Sets the category margin.  An {@link AxisChangeEvent} is sent to all registered
     * listeners.
     *
     * @param margin  the new margin.
     */
    public void setCategoryMargin(double margin) {
        this.categoryMargin = margin;
        notifyListeners(new AxisChangeEvent(this));
    }

    /**
     * Returns a flag indicating whether the category labels are rotated to vertical.
     *
     * @return The flag.
     */
    public boolean isVerticalCategoryLabels() {
        return this.verticalCategoryLabels;
    }

    /**
     * Sets the flag that determines whether the category labels are rotated to vertical.
     *
     * @param flag  the flag.
     */
    public void setVerticalCategoryLabels(boolean flag) {

        if (this.verticalCategoryLabels != flag) {
            this.verticalCategoryLabels = flag;
            notifyListeners(new AxisChangeEvent(this));
        }

    }

    /**
     * Returns the flag that determines whether the category labels are to be
     * skipped to avoid overlapping.
     *
     * @return The flag.
     */
    public boolean getSkipCategoryLabelsToFit() {
        return this.skipCategoryLabelsToFit;
    }

    /**
     * Sets the flag that determines whether the category labels are to be
     * skipped to avoid overlapping.
     *
     * @param flag  the new value of the flag.
     */
    public void setSkipCategoryLabelsToFit(boolean flag) {

        if (this.skipCategoryLabelsToFit != flag) {
            this.skipCategoryLabelsToFit = flag;
            notifyListeners(new AxisChangeEvent(this));
        }

    }

    /**
     * Returns the Java 2D coordinate for a category.
     * 
     * @param anchor  the anchor point.
     * @param category  the category index.
     * @param categoryCount  the category count.
     * @param area  the data area.
     * @param edge  the location of the axis.
     * 
     * @return The coordinate.
     */
    public double getCategoryJava2DCoordinate(CategoryAnchor anchor, 
                                              int category, int categoryCount, Rectangle2D area,
                                              RectangleEdge edge) {
    
        double result = 0.0;
        if (anchor == CategoryAnchor.START) {
            result = getCategoryStart(category, categoryCount, area, edge);
        }
        else if (anchor == CategoryAnchor.MIDDLE) {
            result = getCategoryMiddle(category, categoryCount, area, edge);
        }
        else if (anchor == CategoryAnchor.END) {
            result = getCategoryEnd(category, categoryCount, area, edge);
        }
        return result;
                                                      
    }
                                              
    /**
     * Returns the starting coordinate for the specified category.
     *
     * @param category  the category.
     * @param categoryCount  the number of categories.
     * @param area  the data area.
     * @param edge  the axis location.
     *
     * @return the coordinate.
     */
    public double getCategoryStart(int category, int categoryCount, Rectangle2D area,
                                   RectangleEdge edge) {

        double result = 0.0;
        if ((edge == RectangleEdge.TOP) || (edge == RectangleEdge.BOTTOM)) {
            result = area.getX() + area.getWidth() * getLowerMargin();
        }
        else if ((edge == RectangleEdge.LEFT) || (edge == RectangleEdge.RIGHT)) {
            result = area.getMinY() + area.getHeight() * getLowerMargin();
        }

        double categorySize = calculateCategorySize(categoryCount, area, edge);
        double categoryGapWidth = calculateCategoryGapSize(categoryCount, area, edge);

        result = result + category * (categorySize + categoryGapWidth);

        return result;
    }

    /**
     * Returns the middle coordinate for the specified category.
     *
     * @param category  the category.
     * @param categoryCount  the number of categories.
     * @param area  the data area.
     * @param edge  the axis location.
     *
     * @return the coordinate.
     */
    public double getCategoryMiddle(int category, int categoryCount, Rectangle2D area,
                                    RectangleEdge edge) {