Module platform
Package org.jfree.chart

Class JFreeChart

java.lang.Object
org.jfree.chart.JFreeChart
All Implemented Interfaces:
Serializable, Cloneable, EventListener, PlotChangeListener, TitleChangeListener, Drawable
public class JFreeChart extends Object implements Drawable, TitleChangeListener, PlotChangeListener, Serializable, 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:

  • Field Details

    • DEFAULT_TITLE_FONT

      public static final Font DEFAULT_TITLE_FONT
      The default font for titles.

    • DEFAULT_BACKGROUND_PAINT

      public static final Paint DEFAULT_BACKGROUND_PAINT
      The default background color.

    • DEFAULT_BACKGROUND_IMAGE

      public static final Image DEFAULT_BACKGROUND_IMAGE
      The default background image.

    • DEFAULT_BACKGROUND_IMAGE_ALIGNMENT

      public static final int DEFAULT_BACKGROUND_IMAGE_ALIGNMENT
      The default background image alignment.
      See Also:

    • DEFAULT_BACKGROUND_IMAGE_ALPHA

      public static final float DEFAULT_BACKGROUND_IMAGE_ALPHA
      The default background image alpha.
      See Also:

    • KEY_SUPPRESS_SHADOW_GENERATION

      public static final RenderingHints.Key KEY_SUPPRESS_SHADOW_GENERATION
      The key for a rendering hint that can suppress the generation of a shadow effect when drawing the chart. The hint value must be a Boolean.

  • Constructor Details

    • 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(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(String title, 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 Details

    • getID

      public String getID()
      Returns the ID for the chart.
      Returns:
      The ID for the chart (possibly null).

    • setID

      public void setID(String id)
      Sets the ID for the chart.
      Parameters:
      id - the id (null permitted).

    • getElementHinting

      public boolean getElementHinting()
      Returns the flag that controls whether or not rendering hints (ChartHints.KEY_BEGIN_ELEMENT and ChartHints.KEY_END_ELEMENT) that identify chart elements are added during rendering. The default value is false.
      Returns:
      A boolean.
      See Also:

    • setElementHinting

      public void setElementHinting(boolean hinting)
      Sets the flag that controls whether or not rendering hints (ChartHints.KEY_BEGIN_ELEMENT and ChartHints.KEY_END_ELEMENT) that identify chart elements are added during rendering.
      Parameters:
      hinting - the new flag value.
      See Also:

    • getRenderingHints

      public RenderingHints getRenderingHints()
      Returns the collection of rendering hints for the chart.
      Returns:
      The rendering hints for the chart (never null).
      See Also:

    • setRenderingHints

      public void setRenderingHints(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:

    • 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

      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:

    • getBorderStroke

      public Stroke getBorderStroke()
      Returns the stroke used to draw the chart border (if visible).
      Returns:
      The border stroke.
      See Also:

    • setBorderStroke

      public void setBorderStroke(Stroke stroke)
      Sets the stroke used to draw the chart border (if visible).
      Parameters:
      stroke - the stroke.
      See Also:

    • getBorderPaint

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

    • setBorderPaint

      public void setBorderPaint(Paint paint)
      Sets the paint used to draw the chart border (if visible).
      Parameters:
      paint - the paint.
      See Also:

    • getPadding

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

    • setPadding

      public void setPadding(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:

    • 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

      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:

    • setTitle

      public void setTitle(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:

    • addLegend

      public void addLegend(LegendTitle legend)
      Adds a legend to the plot and sends a ChartChangeEvent to all registered listeners.
      Parameters:
      legend - the legend (null not permitted).
      See Also:

    • 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

      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:

    • removeLegend

      public void removeLegend()
      Removes the first legend in the chart and sends a ChartChangeEvent to all registered listeners.
      See Also:

    • getSubtitles

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

    • setSubtitles

      public void setSubtitles(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:

    • getSubtitleCount

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

    • 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

      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:

    • 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).

    • clearSubtitles

      public void clearSubtitles()
      Clears all subtitles from the chart and sends a ChartChangeEvent to all registered listeners.
      See Also:

    • removeSubtitle

      public void removeSubtitle(Title title)
      Removes the specified subtitle and sends a ChartChangeEvent to all registered listeners.
      Parameters:
      title - the title.
      See Also:

    • 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.

    • getCategoryPlot

      public CategoryPlot getCategoryPlot()
      Returns the plot cast as a CategoryPlot.

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

      Returns:
      The plot.
      See Also:

    • 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:

    • 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

      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:

    • getTextAntiAlias

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

    • 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.
      See Also:

    • setTextAntiAlias

      public void setTextAntiAlias(Object val)
      Sets the value in the rendering hints table for RenderingHints.KEY_TEXT_ANTIALIASING and sends a ChartChangeEvent to all registered listeners.
      Parameters:
      val - the new value (null permitted).
      See Also:

    • getBackgroundPaint

      public Paint getBackgroundPaint()
      Returns the paint used for the chart background.
      Returns:
      The paint (possibly null).
      See Also:

    • setBackgroundPaint

      public void setBackgroundPaint(Paint paint)
      Sets the paint used to fill the chart background and sends a ChartChangeEvent to all registered listeners.
      Parameters:
      paint - the paint (null permitted).
      See Also:

    • getBackgroundImage

      public Image getBackgroundImage()
      Returns the background image for the chart, or null if there is no image.
      Returns:
      The image (possibly null).
      See Also:

    • setBackgroundImage

      public void setBackgroundImage(Image image)
      Sets the background image for the chart and sends a ChartChangeEvent to all registered listeners.
      Parameters:
      image - the image (null permitted).
      See Also:

    • getBackgroundImageAlignment

      public int getBackgroundImageAlignment()
      Returns the background image alignment. Alignment constants are defined in the Align class.
      Returns:
      The alignment.
      See Also:

    • setBackgroundImageAlignment

      public void setBackgroundImageAlignment(int alignment)
      Sets the background alignment. Alignment options are defined by the Align class.
      Parameters:
      alignment - the alignment.
      See Also:

    • getBackgroundImageAlpha

      public float getBackgroundImageAlpha()
      Returns the alpha-transparency for the chart's background image.
      Returns:
      The alpha-transparency.
      See Also:

    • 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:

    • 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

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

    • draw

      public void draw(Graphics2D g2, 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 Drawable
      Parameters:
      g2 - the graphics device.
      area - the area within which the chart should be drawn.

    • draw

      public void draw(Graphics2D g2, 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(Graphics2D g2, Rectangle2D chartArea, 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, Graphics2D g2, 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 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 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 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 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).

    • addChangeListener

      public void addChangeListener(ChartChangeListener listener)
      Registers an object for notification of changes to the chart.
      Parameters:
      listener - the listener (null not permitted).
      See Also:

    • removeChangeListener

      public void removeChangeListener(ChartChangeListener listener)
      Deregisters an object for notification of changes to the chart.
      Parameters:
      listener - the listener (null not permitted)
      See Also:

    • fireChartChanged

      public void fireChartChanged()
      Sends a default ChartChangeEvent to all registered listeners.

      This method is for convenience only.

    • notifyListeners

      protected void notifyListeners(ChartChangeEvent event)
      Sends a ChartChangeEvent to all registered listeners.
      Parameters:
      event - information about the event that triggered the notification.

    • addProgressListener

      public void addProgressListener(ChartProgressListener listener)
      Registers an object for notification of progress events relating to the chart.
      Parameters:
      listener - the object being registered.
      See Also:

    • removeProgressListener

      public void removeProgressListener(ChartProgressListener listener)
      Deregisters an object for notification of changes to the chart.
      Parameters:
      listener - the object being deregistered.
      See Also:

    • notifyListeners

      protected void notifyListeners(ChartProgressEvent event)
      Sends a ChartProgressEvent to all registered listeners.
      Parameters:
      event - information about the event that triggered the notification.

    • titleChanged

      public void titleChanged(TitleChangeEvent event)
      Receives notification that a chart title has changed, and passes this on to registered listeners.
      Specified by:
      titleChanged in interface TitleChangeListener
      Parameters:
      event - information about the chart title change.

    • plotChanged

      public void plotChanged(PlotChangeEvent event)
      Receives notification that the plot has changed, and passes this on to registered listeners.
      Specified by:
      plotChanged in interface PlotChangeListener
      Parameters:
      event - information about the plot change.

    • equals

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

    • clone

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