Package org.jfree.chart.axis

Class NumberAxis

java.lang.Object
org.jfree.chart.axis.Axis
org.jfree.chart.axis.ValueAxis
org.jfree.chart.axis.NumberAxis
All Implemented Interfaces:
Serializable, Cloneable, PublicCloneable
Direct Known Subclasses:
CyclicNumberAxis, LogarithmicAxis, ModuloAxis, SymbolAxis
public class NumberAxis extends ValueAxis implements Cloneable, Serializable
An axis for displaying numerical data.

If the axis is set up to automatically determine its range to fit the data, you can ensure that the range includes zero (statisticians usually prefer this) by setting the autoRangeIncludesZero flag to true.

The NumberAxis class has a mechanism for automatically selecting a tick unit that is appropriate for the current axis range.

See Also:

  • Field Details

  • Constructor Details

    • NumberAxis

      public NumberAxis()
      Default constructor.

    • NumberAxis

      public NumberAxis(String label)
      Constructs a number axis, using default values where necessary.
      Parameters:
      label - the axis label (null permitted).

  • Method Details

    • getRangeType

      public RangeType getRangeType()
      Returns the axis range type.
      Returns:
      The axis range type (never null).
      See Also:

    • setRangeType

      public void setRangeType(RangeType rangeType)
      Sets the axis range type.
      Parameters:
      rangeType - the range type (null not permitted).
      See Also:

    • getAutoRangeIncludesZero

      public boolean getAutoRangeIncludesZero()
      Returns the flag that indicates whether or not the automatic axis range (if indeed it is determined automatically) is forced to include zero.
      Returns:
      The flag.

    • setAutoRangeIncludesZero

      public void setAutoRangeIncludesZero(boolean flag)
      Sets the flag that indicates whether or not the axis range, if automatically calculated, is forced to include zero.

      If the flag is changed to true, the axis range is recalculated.

      Any change to the flag will trigger an AxisChangeEvent.

      Parameters:
      flag - the new value of the flag.
      See Also:

    • getAutoRangeStickyZero

      public boolean getAutoRangeStickyZero()
      Returns a flag that affects the auto-range when zero falls outside the data range but inside the margins defined for the axis.
      Returns:
      The flag.
      See Also:

    • setAutoRangeStickyZero

      public void setAutoRangeStickyZero(boolean flag)
      Sets a flag that affects the auto-range when zero falls outside the data range but inside the margins defined for the axis.
      Parameters:
      flag - the new flag.
      See Also:

    • getTickUnit

      public NumberTickUnit getTickUnit()
      Returns the tick unit for the axis.

      Note: if the autoTickUnitSelection flag is true the tick unit may be changed while the axis is being drawn, so in that case the return value from this method may be irrelevant if the method is called before the axis has been drawn.

      Returns:
      The tick unit for the axis.
      See Also:

    • setTickUnit

      public void setTickUnit(NumberTickUnit unit)
      Sets the tick unit for the axis and sends an AxisChangeEvent to all registered listeners. A side effect of calling this method is that the "auto-select" feature for tick units is switched off (you can restore it using the ValueAxis.setAutoTickUnitSelection(boolean) method).
      Parameters:
      unit - the new tick unit (null not permitted).
      See Also:

    • setTickUnit

      public void setTickUnit(NumberTickUnit unit, boolean notify, boolean turnOffAutoSelect)
      Sets the tick unit for the axis and, if requested, sends an AxisChangeEvent to all registered listeners. In addition, an option is provided to turn off the "auto-select" feature for tick units (you can restore it using the ValueAxis.setAutoTickUnitSelection(boolean) method).
      Parameters:
      unit - the new tick unit (null not permitted).
      notify - notify listeners?
      turnOffAutoSelect - turn off the auto-tick selection?

    • getNumberFormatOverride

      public NumberFormat getNumberFormatOverride()
      Returns the number format override. If this is non-null, then it will be used to format the numbers on the axis.
      Returns:
      The number formatter (possibly null).
      See Also:

    • setNumberFormatOverride

      public void setNumberFormatOverride(NumberFormat formatter)
      Sets the number format override. If this is non-null, then it will be used to format the numbers on the axis.
      Parameters:
      formatter - the number formatter (null permitted).
      See Also:

    • getMarkerBand

      public MarkerAxisBand getMarkerBand()
      Returns the (optional) marker band for the axis.
      Returns:
      The marker band (possibly null).
      See Also:

    • setMarkerBand

      public void setMarkerBand(MarkerAxisBand band)
      Sets the marker band for the axis.

      The marker band is optional, leave it set to null if you don't require it.

      Parameters:
      band - the new band (null permitted).
      See Also:

    • configure

      public void configure()
      Configures the axis to work with the specified plot. If the axis has auto-scaling, then sets the maximum and minimum values.
      Specified by:
      configure in class Axis

    • autoAdjustRange

      protected void autoAdjustRange()
      Rescales the axis to ensure that all data is visible.
      Specified by:
      autoAdjustRange in class ValueAxis

    • valueToJava2D

      public double valueToJava2D(double value, Rectangle2D area, RectangleEdge edge)
      Converts a data value to a coordinate in Java2D space, assuming that the axis runs along one edge of the specified dataArea.

      Note that it is possible for the coordinate to fall outside the plotArea.

      Specified by:
      valueToJava2D in class ValueAxis
      Parameters:
      value - the data value.
      area - the area for plotting the data.
      edge - the axis location.
      Returns:
      The Java2D coordinate.
      See Also:

    • java2DToValue

      public double java2DToValue(double java2DValue, Rectangle2D area, RectangleEdge edge)
      Converts a coordinate in Java2D space to the corresponding data value, assuming that the axis runs along one edge of the specified dataArea.
      Specified by:
      java2DToValue in class ValueAxis
      Parameters:
      java2DValue - the coordinate in Java2D space.
      area - the area in which the data is plotted.
      edge - the location.
      Returns:
      The data value.
      See Also:

    • calculateLowestVisibleTickValue

      protected double calculateLowestVisibleTickValue()
      Calculates the value of the lowest visible tick on the axis.
      Returns:
      The value of the lowest visible tick on the axis.
      See Also:

    • calculateHighestVisibleTickValue

      protected double calculateHighestVisibleTickValue()
      Calculates the value of the highest visible tick on the axis.
      Returns:
      The value of the highest visible tick on the axis.
      See Also:

    • calculateVisibleTickCount

      protected int calculateVisibleTickCount()
      Calculates the number of visible ticks.
      Returns:
      The number of visible ticks on the axis.

    • draw

      public AxisState draw(Graphics2D g2, double cursor, Rectangle2D plotArea, Rectangle2D dataArea, RectangleEdge edge, PlotRenderingInfo plotState)
      Draws the axis on a Java 2D graphics device (such as the screen or a printer).
      Specified by:
      draw in class Axis
      Parameters:
      g2 - the graphics device (null not permitted).
      cursor - the cursor location.
      plotArea - the area within which the axes and data should be drawn (null not permitted).
      dataArea - the area within which the data should be drawn (null not permitted).
      edge - the location of the axis (null not permitted).
      plotState - collects information about the plot (null permitted).
      Returns:
      The axis state (never null).

    • createStandardTickUnits

      public static TickUnitSource createStandardTickUnits()
      Creates the standard tick units.

      If you don't like these defaults, create your own instance of TickUnits and then pass it to the setStandardTickUnits() method in the NumberAxis class.

      Returns:
      The standard tick units.
      See Also:

    • createIntegerTickUnits

      public static TickUnitSource createIntegerTickUnits()
      Returns a collection of tick units for integer values.
      Returns:
      A collection of tick units for integer values.
      See Also:

    • createStandardTickUnits

      public static TickUnitSource createStandardTickUnits(Locale locale)
      Creates a collection of standard tick units. The supplied locale is used to create the number formatter (a localised instance of NumberFormat).

      If you don't like these defaults, create your own instance of TickUnits and then pass it to the setStandardTickUnits() method.

      Parameters:
      locale - the locale.
      Returns:
      A tick unit collection.
      See Also:

    • createIntegerTickUnits

      public static TickUnitSource createIntegerTickUnits(Locale locale)
      Returns a collection of tick units for integer values. Uses a given Locale to create the DecimalFormats.
      Parameters:
      locale - the locale to use to represent Numbers.
      Returns:
      A collection of tick units for integer values.
      See Also:

    • estimateMaximumTickLabelHeight

      protected double estimateMaximumTickLabelHeight(Graphics2D g2)
      Estimates the maximum tick label height.
      Parameters:
      g2 - the graphics device.
      Returns:
      The maximum height.

    • estimateMaximumTickLabelWidth

      protected double estimateMaximumTickLabelWidth(Graphics2D g2, TickUnit unit)
      Estimates the maximum width of the tick labels, assuming the specified tick unit is used.

      Rather than computing the string bounds of every tick on the axis, we just look at two values: the lower bound and the upper bound for the axis. These two values will usually be representative.

      Parameters:
      g2 - the graphics device.
      unit - the tick unit to use for calculation.
      Returns:
      The estimated maximum width of the tick labels.

    • selectAutoTickUnit

      protected void selectAutoTickUnit(Graphics2D g2, Rectangle2D dataArea, RectangleEdge edge)
      Selects an appropriate tick value for the axis. The strategy is to display as many ticks as possible (selected from an array of 'standard' tick units) without the labels overlapping.
      Parameters:
      g2 - the graphics device.
      dataArea - the area defined by the axes.
      edge - the axis location.

    • selectHorizontalAutoTickUnit

      protected void selectHorizontalAutoTickUnit(Graphics2D g2, Rectangle2D dataArea, RectangleEdge edge)
      Selects an appropriate tick value for the axis. The strategy is to display as many ticks as possible (selected from an array of 'standard' tick units) without the labels overlapping.
      Parameters:
      g2 - the graphics device.
      dataArea - the area defined by the axes.
      edge - the axis location.

    • selectVerticalAutoTickUnit

      protected void selectVerticalAutoTickUnit(Graphics2D g2, Rectangle2D dataArea, RectangleEdge edge)
      Selects an appropriate tick value for the axis. The strategy is to display as many ticks as possible (selected from an array of 'standard' tick units) without the labels overlapping.
      Parameters:
      g2 - the graphics device.
      dataArea - the area in which the plot should be drawn.
      edge - the axis location.

    • refreshTicks

      public List refreshTicks(Graphics2D g2, AxisState state, Rectangle2D dataArea, RectangleEdge edge)
      Calculates the positions of the tick labels for the axis, storing the results in the tick label list (ready for drawing).
      Specified by:
      refreshTicks in class Axis
      Parameters:
      g2 - the graphics device.
      state - the axis state.
      dataArea - the area in which the plot should be drawn.
      edge - the location of the axis.
      Returns:
      A list of ticks.

    • refreshTicksHorizontal

      protected List refreshTicksHorizontal(Graphics2D g2, Rectangle2D dataArea, RectangleEdge edge)
      Calculates the positions of the tick labels for the axis, storing the results in the tick label list (ready for drawing).
      Parameters:
      g2 - the graphics device.
      dataArea - the area in which the data should be drawn.
      edge - the location of the axis.
      Returns:
      A list of ticks.

    • refreshTicksVertical

      protected List refreshTicksVertical(Graphics2D g2, Rectangle2D dataArea, RectangleEdge edge)
      Calculates the positions of the tick labels for the axis, storing the results in the tick label list (ready for drawing).
      Parameters:
      g2 - the graphics device.
      dataArea - the area in which the plot should be drawn.
      edge - the location of the axis.
      Returns:
      A list of ticks.

    • clone

      public Object clone() throws CloneNotSupportedException
      Returns a clone of the axis.
      Specified by:
      clone in interface PublicCloneable
      Overrides:
      clone in class ValueAxis
      Returns:
      A clone
      Throws:
      CloneNotSupportedException - if some component of the axis does not support cloning.

    • equals

      public boolean equals(Object obj)
      Tests the axis for equality with an arbitrary object.
      Overrides:
      equals in class ValueAxis
      Parameters:
      obj - the object (null permitted).
      Returns:
      A boolean.

    • hashCode

      public int hashCode()
      Returns a hash code for this object.
      Overrides:
      hashCode in class Axis
      Returns:
      A hash code.