Class JFreeChart

  • All Implemented Interfaces:
    java.io.Serializable, java.lang.Cloneable, java.util.EventListener, PlotChangeListener, TitleChangeListener, org.jfree.ui.Drawable

    public class JFreeChart
    extends java.lang.Object
    implements org.jfree.ui.Drawable, TitleChangeListener, PlotChangeListener, java.io.Serializable, java.lang.Cloneable
    A chart class implemented using the Java 2D APIs. The current version supports bar charts, line charts, pie charts and xy plots (including time series data).

    JFreeChart coordinates several objects to achieve its aim of being able to draw a chart on a Java 2D graphics device: a list of Title objects (which often includes the chart's legend), a Plot and a Dataset (the plot in turn manages a domain axis and a range axis).

    You should use a ChartPanel to display a chart in a GUI.

    The ChartFactory class contains static methods for creating 'ready-made' charts.

    See Also:
    ChartPanel, ChartFactory, Title, Plot, Serialized Form
    • Constructor Summary

      Constructors 
      Constructor Description
      JFreeChart​(java.lang.String title, java.awt.Font titleFont, Plot plot, boolean createLegend)
      Creates a new chart with the given title and plot.
      JFreeChart​(java.lang.String title, Plot plot)
      Creates a new chart with the given title and plot.
      JFreeChart​(Plot plot)
      Creates a new chart based on the supplied plot.
    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void addChangeListener​(ChartChangeListener listener)
      Registers an object for notification of changes to the chart.
      void addLegend​(LegendTitle legend)
      Adds a legend to the plot and sends a ChartChangeEvent to all registered listeners.
      void addProgressListener​(ChartProgressListener listener)
      Registers an object for notification of progress events relating to the chart.
      void addSubtitle​(int index, Title subtitle)
      Adds a subtitle at a particular position in the subtitle list, and sends a ChartChangeEvent to all registered listeners.
      void addSubtitle​(Title subtitle)
      Adds a chart subtitle, and notifies registered listeners that the chart has been modified.
      void clearSubtitles()
      Clears all subtitles from the chart and sends a ChartChangeEvent to all registered listeners.
      java.lang.Object clone()
      Clones the object, and takes care of listeners.
      java.awt.image.BufferedImage createBufferedImage​(int width, int height)
      Creates and returns a buffered image into which the chart has been drawn.
      java.awt.image.BufferedImage createBufferedImage​(int imageWidth, int imageHeight, double drawWidth, double drawHeight, ChartRenderingInfo info)
      Creates and returns a buffered image into which the chart has been drawn.
      java.awt.image.BufferedImage createBufferedImage​(int width, int height, int imageType, ChartRenderingInfo info)
      Creates and returns a buffered image into which the chart has been drawn.
      java.awt.image.BufferedImage createBufferedImage​(int width, int height, ChartRenderingInfo info)
      Creates and returns a buffered image into which the chart has been drawn.
      void draw​(java.awt.Graphics2D g2, java.awt.geom.Rectangle2D area)
      Draws the chart on a Java 2D graphics device (such as the screen or a printer).
      void draw​(java.awt.Graphics2D g2, java.awt.geom.Rectangle2D chartArea, java.awt.geom.Point2D anchor, ChartRenderingInfo info)
      Draws the chart on a Java 2D graphics device (such as the screen or a printer).
      void draw​(java.awt.Graphics2D g2, java.awt.geom.Rectangle2D area, ChartRenderingInfo info)
      Draws the chart on a Java 2D graphics device (such as the screen or a printer).
      protected EntityCollection drawTitle​(Title t, java.awt.Graphics2D g2, java.awt.geom.Rectangle2D area, boolean entities)
      Draws a title.
      boolean equals​(java.lang.Object obj)
      Tests this chart for equality with another object.
      void fireChartChanged()
      Sends a default ChartChangeEvent to all registered listeners.
      boolean getAntiAlias()
      Returns a flag that indicates whether or not anti-aliasing is used when the chart is drawn.
      java.awt.Image getBackgroundImage()
      Returns the background image for the chart, or null if there is no image.
      int getBackgroundImageAlignment()
      Returns the background image alignment.
      float getBackgroundImageAlpha()
      Returns the alpha-transparency for the chart's background image.
      java.awt.Paint getBackgroundPaint()
      Returns the paint used for the chart background.
      java.awt.Paint getBorderPaint()
      Returns the paint used to draw the chart border (if visible).
      java.awt.Stroke getBorderStroke()
      Returns the stroke used to draw the chart border (if visible).
      CategoryPlot getCategoryPlot()
      Returns the plot cast as a CategoryPlot.
      LegendTitle getLegend()
      Returns the legend for the chart, if there is one.
      LegendTitle getLegend​(int index)
      Returns the nth legend for a chart, or null.
      org.jfree.ui.RectangleInsets getPadding()
      Returns the padding between the chart border and the chart drawing area.
      Plot getPlot()
      Returns the plot for the chart.
      java.awt.RenderingHints getRenderingHints()
      Returns the collection of rendering hints for the chart.
      Title getSubtitle​(int index)
      Returns a chart subtitle.
      int getSubtitleCount()
      Returns the number of titles for the chart.
      java.util.List getSubtitles()
      Returns the list of subtitles for the chart.
      java.lang.Object getTextAntiAlias()
      Returns the current value stored in the rendering hints table for RenderingHints.KEY_TEXT_ANTIALIASING.
      TextTitle getTitle()
      Returns the main chart title.
      XYPlot getXYPlot()
      Returns the plot cast as an XYPlot.
      void handleClick​(int x, int y, ChartRenderingInfo info)
      Handles a 'click' on the chart.
      boolean isBorderVisible()
      Returns a flag that controls whether or not a border is drawn around the outside of the chart.
      boolean isNotify()
      Returns a flag that controls whether or not change events are sent to registered listeners.
      static void main​(java.lang.String[] args)
      Prints information about JFreeChart to standard output.
      protected void notifyListeners​(ChartChangeEvent event)
      Sends a ChartChangeEvent to all registered listeners.
      protected void notifyListeners​(ChartProgressEvent event)
      Sends a ChartProgressEvent to all registered listeners.
      void plotChanged​(PlotChangeEvent event)
      Receives notification that the plot has changed, and passes this on to registered listeners.
      void removeChangeListener​(ChartChangeListener listener)
      Deregisters an object for notification of changes to the chart.
      void removeLegend()
      Removes the first legend in the chart and sends a ChartChangeEvent to all registered listeners.
      void removeProgressListener​(ChartProgressListener listener)
      Deregisters an object for notification of changes to the chart.
      void removeSubtitle​(Title title)
      Removes the specified subtitle and sends a ChartChangeEvent to all registered listeners.
      void setAntiAlias​(boolean flag)
      Sets a flag that indicates whether or not anti-aliasing is used when the chart is drawn.
      void setBackgroundImage​(java.awt.Image image)
      Sets the background image for the chart and sends a ChartChangeEvent to all registered listeners.
      void setBackgroundImageAlignment​(int alignment)
      Sets the background alignment.
      void setBackgroundImageAlpha​(float alpha)
      Sets the alpha-transparency for the chart's background image.
      void setBackgroundPaint​(java.awt.Paint paint)
      Sets the paint used to fill the chart background and sends a ChartChangeEvent to all registered listeners.
      void setBorderPaint​(java.awt.Paint paint)
      Sets the paint used to draw the chart border (if visible).
      void setBorderStroke​(java.awt.Stroke stroke)
      Sets the stroke used to draw the chart border (if visible).
      void setBorderVisible​(boolean visible)
      Sets a flag that controls whether or not a border is drawn around the outside of the chart.
      void setNotify​(boolean notify)
      Sets a flag that controls whether or not listeners receive ChartChangeEvent notifications.
      void setPadding​(org.jfree.ui.RectangleInsets padding)
      Sets the padding between the chart border and the chart drawing area, and sends a ChartChangeEvent to all registered listeners.
      void setRenderingHints​(java.awt.RenderingHints renderingHints)
      Sets the rendering hints for the chart.
      void setSubtitles​(java.util.List subtitles)
      Sets the title list for the chart (completely replaces any existing titles) and sends a ChartChangeEvent to all registered listeners.
      void setTextAntiAlias​(boolean flag)
      Sets the value in the rendering hints table for RenderingHints.KEY_TEXT_ANTIALIASING to either RenderingHints.VALUE_TEXT_ANTIALIAS_ON or RenderingHints.VALUE_TEXT_ANTIALIAS_OFF, then sends a ChartChangeEvent to all registered listeners.
      void setTextAntiAlias​(java.lang.Object val)
      Sets the value in the rendering hints table for RenderingHints.KEY_TEXT_ANTIALIASING and sends a ChartChangeEvent to all registered listeners.
      void setTitle​(java.lang.String text)
      Sets the chart title and sends a ChartChangeEvent to all registered listeners.
      void setTitle​(TextTitle title)
      Sets the main title for the chart and sends a ChartChangeEvent to all registered listeners.
      void titleChanged​(TitleChangeEvent event)
      Receives notification that a chart title has changed, and passes this on to registered listeners.
      • Methods inherited from class java.lang.Object

        finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    • Constructor Detail

      • JFreeChart

        public JFreeChart​(Plot plot)
        Creates a new chart based on the supplied plot. The chart will have a legend added automatically, but no title (although you can easily add one later).

        Note that the ChartFactory class contains a range of static methods that will return ready-made charts, and often this is a more convenient way to create charts than using this constructor.
        Parameters:
        plot - the plot (null not permitted).
      • JFreeChart

        public JFreeChart​(java.lang.String title,
                          Plot plot)
        Creates a new chart with the given title and plot. A default font (DEFAULT_TITLE_FONT) is used for the title, and the chart will have a legend added automatically.

        Note that the ChartFactory class contains a range of static methods that will return ready-made charts, and often this is a more convenient way to create charts than using this constructor.
        Parameters:
        title - the chart title (null permitted).
        plot - the plot (null not permitted).
      • JFreeChart

        public JFreeChart​(java.lang.String title,
                          java.awt.Font titleFont,
                          Plot plot,
                          boolean createLegend)
        Creates a new chart with the given title and plot. The createLegend argument specifies whether or not a legend should be added to the chart.

        Note that the ChartFactory class contains a range of static methods that will return ready-made charts, and often this is a more convenient way to create charts than using this constructor.
        Parameters:
        title - the chart title (null permitted).
        titleFont - the font for displaying the chart title (null permitted).
        plot - controller of the visual representation of the data (null not permitted).
        createLegend - a flag indicating whether or not a legend should be created for the chart.
    • Method Detail

      • setRenderingHints

        public void setRenderingHints​(java.awt.RenderingHints renderingHints)
        Sets the rendering hints for the chart. These will be added (using the Graphics2D.addRenderingHints() method) near the start of the JFreeChart.draw() method.
        Parameters:
        renderingHints - the rendering hints (null not permitted).
        See Also:
        getRenderingHints()
      • isBorderVisible

        public boolean isBorderVisible()
        Returns a flag that controls whether or not a border is drawn around the outside of the chart.
        Returns:
        A boolean.
        See Also:
        setBorderVisible(boolean)
      • setBorderVisible

        public void setBorderVisible​(boolean visible)
        Sets a flag that controls whether or not a border is drawn around the outside of the chart.
        Parameters:
        visible - the flag.
        See Also:
        isBorderVisible()
      • setBorderStroke

        public void setBorderStroke​(java.awt.Stroke stroke)
        Sets the stroke used to draw the chart border (if visible).
        Parameters:
        stroke - the stroke.
        See Also:
        getBorderStroke()
      • getBorderPaint

        public java.awt.Paint getBorderPaint()
        Returns the paint used to draw the chart border (if visible).
        Returns:
        The border paint.
        See Also:
        setBorderPaint(Paint)
      • setBorderPaint

        public void setBorderPaint​(java.awt.Paint paint)
        Sets the paint used to draw the chart border (if visible).
        Parameters:
        paint - the paint.
        See Also:
        getBorderPaint()
      • getPadding

        public org.jfree.ui.RectangleInsets getPadding()
        Returns the padding between the chart border and the chart drawing area.
        Returns:
        The padding (never null).
        See Also:
        setPadding(RectangleInsets)
      • setPadding

        public void setPadding​(org.jfree.ui.RectangleInsets padding)
        Sets the padding between the chart border and the chart drawing area, and sends a ChartChangeEvent to all registered listeners.
        Parameters:
        padding - the padding (null not permitted).
        See Also:
        getPadding()
      • getTitle

        public TextTitle getTitle()
        Returns the main chart title. Very often a chart will have just one title, so we make this case simple by providing accessor methods for the main title. However, multiple titles are supported - see the addSubtitle(Title) method.
        Returns:
        The chart title (possibly null).
        See Also:
        setTitle(TextTitle)
      • setTitle

        public void setTitle​(TextTitle title)
        Sets the main title for the chart and sends a ChartChangeEvent to all registered listeners. If you do not want a title for the chart, set it to null. If you want more than one title on a chart, use the addSubtitle(Title) method.
        Parameters:
        title - the title (null permitted).
        See Also:
        getTitle()
      • setTitle

        public void setTitle​(java.lang.String text)
        Sets the chart title and sends a ChartChangeEvent to all registered listeners. This is a convenience method that ends up calling the setTitle(TextTitle) method. If there is an existing title, its text is updated, otherwise a new title using the default font is added to the chart. If text is null the chart title is set to null.
        Parameters:
        text - the title text (null permitted).
        See Also:
        getTitle()
      • getLegend

        public LegendTitle getLegend()
        Returns the legend for the chart, if there is one. Note that a chart can have more than one legend - this method returns the first.
        Returns:
        The legend (possibly null).
        See Also:
        getLegend(int)
      • getLegend

        public LegendTitle getLegend​(int index)
        Returns the nth legend for a chart, or null.
        Parameters:
        index - the legend index (zero-based).
        Returns:
        The legend (possibly null).
        See Also:
        addLegend(LegendTitle)
      • getSubtitles

        public java.util.List getSubtitles()
        Returns the list of subtitles for the chart.
        Returns:
        The subtitle list (possibly empty, but never null).
        See Also:
        setSubtitles(List)
      • setSubtitles

        public void setSubtitles​(java.util.List subtitles)
        Sets the title list for the chart (completely replaces any existing titles) and sends a ChartChangeEvent to all registered listeners.
        Parameters:
        subtitles - the new list of subtitles (null not permitted).
        See Also:
        getSubtitles()
      • getSubtitleCount

        public int getSubtitleCount()
        Returns the number of titles for the chart.
        Returns:
        The number of titles for the chart.
        See Also:
        getSubtitles()
      • getSubtitle

        public Title getSubtitle​(int index)
        Returns a chart subtitle.
        Parameters:
        index - the index of the chart subtitle (zero based).
        Returns:
        A chart subtitle.
        See Also:
        addSubtitle(Title)
      • addSubtitle

        public void addSubtitle​(Title subtitle)
        Adds a chart subtitle, and notifies registered listeners that the chart has been modified.
        Parameters:
        subtitle - the subtitle (null not permitted).
        See Also:
        getSubtitle(int)
      • addSubtitle

        public void addSubtitle​(int index,
                                Title subtitle)
        Adds a subtitle at a particular position in the subtitle list, and sends a ChartChangeEvent to all registered listeners.
        Parameters:
        index - the index (in the range 0 to getSubtitleCount()).
        subtitle - the subtitle to add (null not permitted).
        Since:
        1.0.6
      • getPlot

        public Plot getPlot()
        Returns the plot for the chart. The plot is a class responsible for coordinating the visual representation of the data, including the axes (if any).
        Returns:
        The plot.
      • getXYPlot

        public XYPlot getXYPlot()
        Returns the plot cast as an XYPlot.

        NOTE: if the plot is not an instance of XYPlot, then a ClassCastException is thrown.

        Returns:
        The plot.
        See Also:
        getPlot()
      • getAntiAlias

        public boolean getAntiAlias()
        Returns a flag that indicates whether or not anti-aliasing is used when the chart is drawn.
        Returns:
        The flag.
        See Also:
        setAntiAlias(boolean)
      • setAntiAlias

        public void setAntiAlias​(boolean flag)
        Sets a flag that indicates whether or not anti-aliasing is used when the chart is drawn.

        Anti-aliasing usually improves the appearance of charts, but is slower.

        Parameters:
        flag - the new value of the flag.
        See Also:
        getAntiAlias()
      • getTextAntiAlias

        public java.lang.Object getTextAntiAlias()
        Returns the current value stored in the rendering hints table for RenderingHints.KEY_TEXT_ANTIALIASING.
        Returns:
        The hint value (possibly null).
        Since:
        1.0.5
        See Also:
        setTextAntiAlias(Object)
      • setTextAntiAlias

        public void setTextAntiAlias​(boolean flag)
        Sets the value in the rendering hints table for RenderingHints.KEY_TEXT_ANTIALIASING to either RenderingHints.VALUE_TEXT_ANTIALIAS_ON or RenderingHints.VALUE_TEXT_ANTIALIAS_OFF, then sends a ChartChangeEvent to all registered listeners.
        Parameters:
        flag - the new value of the flag.
        Since:
        1.0.5
        See Also:
        getTextAntiAlias(), setTextAntiAlias(Object)
      • setBackgroundImageAlpha

        public void setBackgroundImageAlpha​(float alpha)
        Sets the alpha-transparency for the chart's background image. Registered listeners are notified that the chart has been changed.
        Parameters:
        alpha - the alpha value.
        See Also:
        getBackgroundImageAlpha()
      • isNotify

        public boolean isNotify()
        Returns a flag that controls whether or not change events are sent to registered listeners.
        Returns:
        A boolean.
        See Also:
        setNotify(boolean)
      • setNotify

        public void setNotify​(boolean notify)
        Sets a flag that controls whether or not listeners receive ChartChangeEvent notifications.
        Parameters:
        notify - a boolean.
        See Also:
        isNotify()
      • draw

        public void draw​(java.awt.Graphics2D g2,
                         java.awt.geom.Rectangle2D area)
        Draws the chart on a Java 2D graphics device (such as the screen or a printer).

        This method is the focus of the entire JFreeChart library.

        Specified by:
        draw in interface org.jfree.ui.Drawable
        Parameters:
        g2 - the graphics device.
        area - the area within which the chart should be drawn.
      • draw

        public void draw​(java.awt.Graphics2D g2,
                         java.awt.geom.Rectangle2D area,
                         ChartRenderingInfo info)
        Draws the chart on a Java 2D graphics device (such as the screen or a printer). This method is the focus of the entire JFreeChart library.
        Parameters:
        g2 - the graphics device.
        area - the area within which the chart should be drawn.
        info - records info about the drawing (null means collect no info).
      • draw

        public void draw​(java.awt.Graphics2D g2,
                         java.awt.geom.Rectangle2D chartArea,
                         java.awt.geom.Point2D anchor,
                         ChartRenderingInfo info)
        Draws the chart on a Java 2D graphics device (such as the screen or a printer).

        This method is the focus of the entire JFreeChart library.

        Parameters:
        g2 - the graphics device.
        chartArea - the area within which the chart should be drawn.
        anchor - the anchor point (in Java2D space) for the chart (null permitted).
        info - records info about the drawing (null means collect no info).
      • drawTitle

        protected EntityCollection drawTitle​(Title t,
                                             java.awt.Graphics2D g2,
                                             java.awt.geom.Rectangle2D area,
                                             boolean entities)
        Draws a title. The title should be drawn at the top, bottom, left or right of the specified area, and the area should be updated to reflect the amount of space used by the title.
        Parameters:
        t - the title (null not permitted).
        g2 - the graphics device (null not permitted).
        area - the chart area, excluding any existing titles (null not permitted).
        entities - a flag that controls whether or not an entity collection is returned for the title.
        Returns:
        An entity collection for the title (possibly null).
      • createBufferedImage

        public java.awt.image.BufferedImage createBufferedImage​(int width,
                                                                int height)
        Creates and returns a buffered image into which the chart has been drawn.
        Parameters:
        width - the width.
        height - the height.
        Returns:
        A buffered image.
      • createBufferedImage

        public java.awt.image.BufferedImage createBufferedImage​(int width,
                                                                int height,
                                                                ChartRenderingInfo info)
        Creates and returns a buffered image into which the chart has been drawn.
        Parameters:
        width - the width.
        height - the height.
        info - carries back chart state information (null permitted).
        Returns:
        A buffered image.
      • createBufferedImage

        public java.awt.image.BufferedImage createBufferedImage​(int width,
                                                                int height,
                                                                int imageType,
                                                                ChartRenderingInfo info)
        Creates and returns a buffered image into which the chart has been drawn.
        Parameters:
        width - the width.
        height - the height.
        imageType - the image type.
        info - carries back chart state information (null permitted).
        Returns:
        A buffered image.
      • createBufferedImage

        public java.awt.image.BufferedImage createBufferedImage​(int imageWidth,
                                                                int imageHeight,
                                                                double drawWidth,
                                                                double drawHeight,
                                                                ChartRenderingInfo info)
        Creates and returns a buffered image into which the chart has been drawn.
        Parameters:
        imageWidth - the image width.
        imageHeight - the image height.
        drawWidth - the width for drawing the chart (will be scaled to fit image).
        drawHeight - the height for drawing the chart (will be scaled to fit image).
        info - optional object for collection chart dimension and entity information.
        Returns:
        A buffered image.
      • handleClick

        public void handleClick​(int x,
                                int y,
                                ChartRenderingInfo info)
        Handles a 'click' on the chart. JFreeChart is not a UI component, so some other object (for example, ChartPanel) needs to capture the click event and pass it onto the JFreeChart object. If you are not using JFreeChart in a client application, then this method is not required.
        Parameters:
        x - x-coordinate of the click (in Java2D space).
        y - y-coordinate of the click (in Java2D space).
        info - contains chart dimension and entity information (null not permitted).
      • equals

        public boolean equals​(java.lang.Object obj)
        Tests this chart for equality with another object.
        Overrides:
        equals in class java.lang.Object
        Parameters:
        obj - the object (null permitted).
        Returns:
        A boolean.
      • main

        public static void main​(java.lang.String[] args)
        Prints information about JFreeChart to standard output.
        Parameters:
        args - no arguments are honored.
      • clone

        public java.lang.Object clone()
                               throws java.lang.CloneNotSupportedException
        Clones the object, and takes care of listeners. Note: caller shall register its own listeners on cloned graph.
        Overrides:
        clone in class java.lang.Object
        Returns:
        A clone.
        Throws:
        java.lang.CloneNotSupportedException - if the chart is not cloneable.