## org.jfree.chart.axis
Class DateAxis

    java.lang.Object
      org.jfree.chart.axis.Axis
          org.jfree.chart.axis.ValueAxis
              org.jfree.chart.axis.DateAxis

All Implemented Interfaces:
  java.io.Serializable, java.lang.Cloneable, org.jfree.util.PublicCloneable

    public class DateAxis

extends ValueAxis
implements java.lang.Cloneable, java.io.Serializable

The base class for axes that display dates. You will find it easier to understand how this axis works if you bear in mind that it really displays/measures integer (or long) data, where the integers are milliseconds since midnight, 1-Jan-1970. When displaying tick labels, the millisecond values are converted back to dates using a `DateFormat` instance.

You can also create a `Timeline` and supply in the constructor to create an axis that only contains certain domain values. For example, this allows you to create a date axis that only contains working days.

See Also:
  Serialized Form

Field Summary
`static java.util.Date` `DEFAULT_ANCHOR_DATE` The default anchor date.
`static double` `DEFAULT_AUTO_RANGE_MINIMUM_SIZE_IN_MILLISECONDS` The default minimum auto range size.
`static DateRange` `DEFAULT_DATE_RANGE` The default axis range.
`static DateTickUnit` `DEFAULT_DATE_TICK_UNIT` The default date tick unit.

Fields inherited from class org.jfree.chart.axis.ValueAxis
`DEFAULT_AUTO_RANGE, DEFAULT_AUTO_RANGE_MINIMUM_SIZE, DEFAULT_AUTO_TICK_UNIT_SELECTION, DEFAULT_INVERTED, DEFAULT_LOWER_BOUND, DEFAULT_LOWER_MARGIN, DEFAULT_RANGE, DEFAULT_UPPER_BOUND, DEFAULT_UPPER_MARGIN, MAXIMUM_TICK_COUNT`

Fields inherited from class org.jfree.chart.axis.Axis

`DEFAULT_AXIS_LABEL_FONT, DEFAULT_AXIS_LABEL_INSETS, DEFAULT_AXIS_LABEL_PAINT, DEFAULT_AXIS_LINE_PAINT, DEFAULT_AXIS_LINE_STROKE, DEFAULT_AXIS_VISIBLE, DEFAULT_TICK_LABEL_FONT, DEFAULT_TICK_LABEL_INSETS, DEFAULT_TICK_LABEL_PAINT, DEFAULT_TICK_LABELS_VISIBLE, DEFAULT_TICK_MARK_INSIDE_LENGTH, DEFAULT_TICK_MARK_OUTSIDE_LENGTH, DEFAULT_TICK_MARK_PAINT, DEFAULT_TICK_MARK_STROKE, DEFAULT_TICK_MARKS_VISIBLE`

Constructor Summary
`DateAxis()` Creates a date axis with no label.
`DateAxis(java.lang.String label)` Creates a date axis with the specified label.
`DateAxis(java.lang.String label, java.util.TimeZone zone)` Creates a date axis.

Method Summary
`protected void` `autoAdjustRange()` Rescales the axis to ensure that all data is visible.
`java.util.Date` `calculateHighestVisibleTickValue(DateTickUnit unit)` Calculates the value of the highest visible tick on the axis.
`java.util.Date` `calculateLowestVisibleTickValue(DateTickUnit unit)` Calculates the value of the lowest visible tick on the axis.
`java.lang.Object` `clone()` Returns a clone of the object.
`void` `configure()` Configures the axis to work with the specified plot.
`static TickUnitSource` `createStandardDateTickUnits()` Returns a collection of standard date tick units that uses the default time zone.
`static TickUnitSource` `createStandardDateTickUnits(java.util.TimeZone zone)` Returns a collection of standard date tick units.
`double` `dateToJava2D(java.util.Date date, java.awt.geom.Rectangle2D area, org.jfree.ui.RectangleEdge edge)` Translates a date to Java2D coordinates, based on the range displayed by this axis for the specified data area.
`AxisState` `draw(java.awt.Graphics2D g2, double cursor, java.awt.geom.Rectangle2D plotArea, java.awt.geom.Rectangle2D dataArea, org.jfree.ui.RectangleEdge edge, PlotRenderingInfo plotState)` Draws the axis on a Java 2D graphics device (such as the screen or a printer).
`boolean` `equals(java.lang.Object obj)` Tests this axis for equality with an arbitrary object.
`java.text.DateFormat` `getDateFormatOverride()` Returns the date format override.
`java.util.Date` `getMaximumDate()` Returns the latest date visible on the axis.
`java.util.Date` `getMinimumDate()` Returns the earliest date visible on the axis.
`DateTickMarkPosition` `getTickMarkPosition()` Returns the tick mark position (start, middle or end of the time period).
`DateTickUnit` `getTickUnit()` Returns the tick unit for the axis.
`Timeline` `getTimeline()` Returns the underlying timeline used by this axis.
`java.util.TimeZone` `getTimeZone()` Returns the time zone for the axis.
`int` `hashCode()` Returns a hash code for this object.
`boolean` `isHiddenValue(long millis)` Returns `true` if the axis hides this value, and `false` otherwise.
`double` `java2DToValue(double java2DValue, java.awt.geom.Rectangle2D area, org.jfree.ui.RectangleEdge edge)` Translates a Java2D coordinate into the corresponding data value.
`protected java.util.Date` `nextStandardDate(java.util.Date date, DateTickUnit unit)` Returns the first "standard" date (based on the specified field and units).
`protected java.util.Date` `previousStandardDate(java.util.Date date, DateTickUnit unit)` Returns the previous "standard" date, for a given date and tick unit.
`java.util.List` `refreshTicks(java.awt.Graphics2D g2, AxisState state, java.awt.geom.Rectangle2D dataArea, org.jfree.ui.RectangleEdge edge)` Calculates the positions of the tick labels for the axis, storing the results in the tick label list (ready for drawing).
`protected java.util.List` `refreshTicksHorizontal(java.awt.Graphics2D g2, java.awt.geom.Rectangle2D dataArea, org.jfree.ui.RectangleEdge edge)` Recalculates the ticks for the date axis.
`protected java.util.List` `refreshTicksVertical(java.awt.Graphics2D g2, java.awt.geom.Rectangle2D dataArea, org.jfree.ui.RectangleEdge edge)` Recalculates the ticks for the date axis.
`protected void` `selectAutoTickUnit(java.awt.Graphics2D g2, java.awt.geom.Rectangle2D dataArea, org.jfree.ui.RectangleEdge edge)` Selects an appropriate tick value for the axis.
`protected void` `selectHorizontalAutoTickUnit(java.awt.Graphics2D g2, java.awt.geom.Rectangle2D dataArea, org.jfree.ui.RectangleEdge edge)` Selects an appropriate tick size for the axis.
`protected void` `selectVerticalAutoTickUnit(java.awt.Graphics2D g2, java.awt.geom.Rectangle2D dataArea, org.jfree.ui.RectangleEdge edge)` Selects an appropriate tick size for the axis.
`void` `setDateFormatOverride(java.text.DateFormat formatter)` Sets the date format override.
`void` `setMaximumDate(java.util.Date maximumDate)` Sets the maximum date visible on the axis and sends an `AxisChangeEvent` to all registered listeners.
`void` `setMinimumDate(java.util.Date date)` Sets the minimum date visible on the axis and sends an `AxisChangeEvent` to all registered listeners.
`void` `setRange(java.util.Date lower, java.util.Date upper)` Sets the axis range and sends an `AxisChangeEvent` to all registered listeners.
`void` `setRange(double lower, double upper)` Sets the axis range and sends an `AxisChangeEvent` to all registered listeners.
`void` `setRange(Range range)` Sets the upper and lower bounds for the axis and sends an `AxisChangeEvent` to all registered listeners.
`void` `setRange(Range range, boolean turnOffAutoRange, boolean notify)` Sets the range for the axis, if requested, sends an `AxisChangeEvent` to all registered listeners.
`void` `setTickMarkPosition(DateTickMarkPosition position)` Sets the tick mark position (start, middle or end of the time period) and sends an `AxisChangeEvent` to all registered listeners.
`void` `setTickUnit(DateTickUnit unit)` Sets the tick unit for the axis.
`void` `setTickUnit(DateTickUnit unit, boolean notify, boolean turnOffAutoSelection)` Sets the tick unit attribute.
`void` `setTimeline(Timeline timeline)` Sets the underlying timeline to use for this axis.
`void` `setTimeZone(java.util.TimeZone zone)` Sets the time zone for the axis and sends an `AxisChangeEvent` to all registered listeners.
`double` `valueToJava2D(double value, java.awt.geom.Rectangle2D area, org.jfree.ui.RectangleEdge edge)` Translates the data value to the display coordinates (Java 2D User Space) of the chart.
`void` `zoomRange(double lowerPercent, double upperPercent)` Zooms in on the current range.

Methods inherited from class org.jfree.chart.axis.ValueAxis

`calculateAnchorPoint, centerRange, drawAxisLine, drawTickMarksAndLabels, findMaximumTickLabelHeight, findMaximumTickLabelWidth, getAutoRangeMinimumSize, getAutoTickIndex, getDefaultAutoRange, getDownArrow, getFixedAutoRange, getLeftArrow, getLowerBound, getLowerMargin, getRange, getRightArrow, getStandardTickUnits, getUpArrow, getUpperBound, getUpperMargin, isAutoRange, isAutoTickUnitSelection, isInverted, isNegativeArrowVisible, isPositiveArrowVisible, isVerticalTickLabels, lengthToJava2D, reserveSpace, resizeRange, resizeRange, setAutoRange, setAutoRange, setAutoRangeMinimumSize, setAutoRangeMinimumSize, setAutoTickIndex, setAutoTickUnitSelection, setAutoTickUnitSelection, setDefaultAutoRange, setDownArrow, setFixedAutoRange, setInverted, setLeftArrow, setLowerBound, setLowerMargin, setNegativeArrowVisible, setPositiveArrowVisible, setRangeAboutValue, setRangeWithMargins, setRangeWithMargins, setRangeWithMargins, setRightArrow, setStandardTickUnits, setUpArrow, setUpperBound, setUpperMargin, setVerticalTickLabels`

Methods inherited from class org.jfree.chart.axis.Axis

`addChangeListener, drawLabel, getAxisLinePaint, getAxisLineStroke, getFixedDimension, getLabel, getLabelAngle, getLabelEnclosure, getLabelFont, getLabelInsets, getLabelPaint, getPlot, getTickLabelFont, getTickLabelInsets, getTickLabelPaint, getTickMarkInsideLength, getTickMarkOutsideLength, getTickMarkPaint, getTickMarkStroke, hasListener, isAxisLineVisible, isTickLabelsVisible, isTickMarksVisible, isVisible, notifyListeners, removeChangeListener, setAxisLinePaint, setAxisLineStroke, setAxisLineVisible, setFixedDimension, setLabel, setLabelAngle, setLabelFont, setLabelInsets, setLabelInsets, setLabelPaint, setPlot, setTickLabelFont, setTickLabelInsets, setTickLabelPaint, setTickLabelsVisible, setTickMarkInsideLength, setTickMarkOutsideLength, setTickMarkPaint, setTickMarkStroke, setTickMarksVisible, setVisible`

Methods inherited from class java.lang.Object
`finalize, getClass, notify, notifyAll, toString, wait, wait, wait`

Field Detail

### DEFAULT_DATE_RANGE

    public static final DateRange DEFAULT_DATE_RANGE

  The default axis range.

### DEFAULT_AUTO_RANGE_MINIMUM_SIZE_IN_MILLISECONDS

    public static final double DEFAULT_AUTO_RANGE_MINIMUM_SIZE_IN_MILLISECONDS

  The default minimum auto range size.

  See Also:
    Constant Field Values

### DEFAULT_DATE_TICK_UNIT

    public static final DateTickUnit DEFAULT_DATE_TICK_UNIT

  The default date tick unit.

### DEFAULT_ANCHOR_DATE

    public static final java.util.Date DEFAULT_ANCHOR_DATE

  The default anchor date.

Constructor Detail

### DateAxis

    public DateAxis()

  Creates a date axis with no label.

### DateAxis

    public DateAxis(java.lang.String label)

  Creates a date axis with the specified label.

  Parameters:
    `label` - the axis label (`null` permitted).

### DateAxis

    public DateAxis(java.lang.String label,
                    java.util.TimeZone zone)

  Creates a date axis. A timeline is specified for the axis. This allows special transformations to occur between a domain of values and the values included in the axis.

  Parameters:
    `label` - the axis label (`null` permitted).
    `zone` - the time zone.
  See Also:
    `SegmentedTimeline`

Method Detail

### getTimeZone

    public java.util.TimeZone getTimeZone()

  Returns the time zone for the axis.

  Returns:
    The time zone.
  Since:
    1.0.4
  See Also:
    `setTimeZone(TimeZone)`

### setTimeZone

    public void setTimeZone(java.util.TimeZone zone)

  Sets the time zone for the axis and sends an `AxisChangeEvent` to all registered listeners.

  Parameters:
    `zone` - the time zone (`null` not permitted).
  Since:
    1.0.4
  See Also:
    `getTimeZone()`

### getTimeline

    public Timeline getTimeline()

  Returns the underlying timeline used by this axis.

  Returns:
    The timeline.

### setTimeline

    public void setTimeline(Timeline timeline)

  Sets the underlying timeline to use for this axis.

  If the timeline is changed, an `AxisChangeEvent` is sent to all registered listeners.

  Parameters:
    `timeline` - the timeline.

### getTickUnit

    public DateTickUnit 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 (possibly `null`).
  See Also:
    `setTickUnit(DateTickUnit)`, `ValueAxis.isAutoTickUnitSelection()`

### setTickUnit

    public void setTickUnit(DateTickUnit unit)

  Sets the tick unit for the axis. The auto-tick-unit-selection flag is set to `false`, and registered listeners are notified that the axis has been changed.

  Parameters:
    `unit` - the tick unit.
  See Also:
    `getTickUnit()`, `setTickUnit(DateTickUnit, boolean, boolean)`

### setTickUnit

    public void setTickUnit(DateTickUnit unit,
                            boolean notify,
                            boolean turnOffAutoSelection)

  Sets the tick unit attribute.

  Parameters:
    `unit` - the new tick unit.
    `notify` - notify registered listeners?
    `turnOffAutoSelection` - turn off auto selection?
  See Also:
    `getTickUnit()`

### getDateFormatOverride

    public java.text.DateFormat getDateFormatOverride()

  Returns the date format override. If this is non-null, then it will be used to format the dates on the axis.

  Returns:
    The formatter (possibly `null`).

### setDateFormatOverride

    public void setDateFormatOverride(java.text.DateFormat formatter)

  Sets the date format override. If this is non-null, then it will be used to format the dates on the axis.

  Parameters:
    `formatter` - the date formatter (`null` permitted).

### setRange

    public void setRange(Range range)

  Sets the upper and lower bounds for the axis and sends an `AxisChangeEvent` to all registered listeners. As a side-effect, the auto-range flag is set to false.

  Overrides:
    `setRange` in class `ValueAxis`
  Parameters:
    `range` - the new range (`null` not permitted).
  See Also:
    `ValueAxis.getRange()`

### setRange

    public void setRange(Range range,
                         boolean turnOffAutoRange,
                         boolean notify)

  Sets the range for the axis, if requested, sends an `AxisChangeEvent` to all registered listeners. As a side-effect, the auto-range flag is set to `false` (optional).

  Overrides:
    `setRange` in class `ValueAxis`
  Parameters:
    `range` - the range (`null` not permitted).
    `turnOffAutoRange` - a flag that controls whether or not the auto range is turned off.
    `notify` - a flag that controls whether or not listeners are notified.
  See Also:
    `ValueAxis.getRange()`

### setRange

    public void setRange(java.util.Date lower,
                         java.util.Date upper)

  Sets the axis range and sends an `AxisChangeEvent` to all registered listeners.

  Parameters:
    `lower` - the lower bound for the axis.
    `upper` - the upper bound for the axis.

### setRange

    public void setRange(double lower,
                         double upper)

  Sets the axis range and sends an `AxisChangeEvent` to all registered listeners.

  Overrides:
    `setRange` in class `ValueAxis`
  Parameters:
    `lower` - the lower bound for the axis.
    `upper` - the upper bound for the axis.
  See Also:
    `ValueAxis.getRange()`, `ValueAxis.setRange(Range)`

### getMinimumDate

    public java.util.Date getMinimumDate()

  Returns the earliest date visible on the axis.

  Returns:
    The date.
  See Also:
    `setMinimumDate(Date)`, `getMaximumDate()`

### setMinimumDate

    public void setMinimumDate(java.util.Date date)

  Sets the minimum date visible on the axis and sends an `AxisChangeEvent` to all registered listeners. If `date` is on or after the current maximum date for the axis, the maximum date will be shifted to preserve the current length of the axis.

  Parameters:
    `date` - the date (`null` not permitted).
  See Also:
    `getMinimumDate()`, `setMaximumDate(Date)`

### getMaximumDate

    public java.util.Date getMaximumDate()

  Returns the latest date visible on the axis.

  Returns:
    The date.
  See Also:
    `setMaximumDate(Date)`, `getMinimumDate()`

### setMaximumDate

    public void setMaximumDate(java.util.Date maximumDate)

  Sets the maximum date visible on the axis and sends an `AxisChangeEvent` to all registered listeners. If `maximumDate` is on or before the current minimum date for the axis, the minimum date will be shifted to preserve the current length of the axis.

  Parameters:
    `maximumDate` - the date (`null` not permitted).
  See Also:
    `getMinimumDate()`, `setMinimumDate(Date)`

### getTickMarkPosition

    public DateTickMarkPosition getTickMarkPosition()

  Returns the tick mark position (start, middle or end of the time period).

  Returns:
    The position (never `null`).

### setTickMarkPosition

    public void setTickMarkPosition(DateTickMarkPosition position)

  Sets the tick mark position (start, middle or end of the time period) and sends an `AxisChangeEvent` to all registered listeners.

  Parameters:
    `position` - the position (`null` not permitted).

### 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`

### isHiddenValue

    public boolean isHiddenValue(long millis)

  Returns `true` if the axis hides this value, and `false` otherwise.

  Parameters:
    `millis` - the data value.
  Returns:
    A value.

### valueToJava2D

    public double valueToJava2D(double value,
                                java.awt.geom.Rectangle2D area,
                                org.jfree.ui.RectangleEdge edge)

  Translates the data value to the display coordinates (Java 2D User Space) of the chart.

  Specified by:
    `valueToJava2D` in class `ValueAxis`
  Parameters:
    `value` - the date to be plotted.
    `area` - the rectangle (in Java2D space) where the data is to be plotted.
    `edge` - the axis location.
  Returns:
    The coordinate corresponding to the supplied data value.
  See Also:
    `ValueAxis.java2DToValue(double, Rectangle2D, RectangleEdge)`

### dateToJava2D

    public double dateToJava2D(java.util.Date date,
                               java.awt.geom.Rectangle2D area,
                               org.jfree.ui.RectangleEdge edge)

  Translates a date to Java2D coordinates, based on the range displayed by this axis for the specified data area.

  Parameters:
    `date` - the date.
    `area` - the rectangle (in Java2D space) where the data is to be plotted.
    `edge` - the axis location.
  Returns:
    The coordinate corresponding to the supplied date.

### java2DToValue

    public double java2DToValue(double java2DValue,
                                java.awt.geom.Rectangle2D area,
                                org.jfree.ui.RectangleEdge edge)

  Translates a Java2D coordinate into the corresponding data value. To perform this translation, you need to know the area used for plotting data, and which edge the axis is located on.

  Specified by:
    `java2DToValue` in class `ValueAxis`
  Parameters:
    `java2DValue` - the coordinate in Java2D space.
    `area` - the rectangle (in Java2D space) where the data is to be plotted.
    `edge` - the axis location.
  Returns:
    A data value.
  See Also:
    `ValueAxis.valueToJava2D(double, Rectangle2D, RectangleEdge)`

### calculateLowestVisibleTickValue

    public java.util.Date calculateLowestVisibleTickValue(DateTickUnit unit)

  Calculates the value of the lowest visible tick on the axis.

  Parameters:
    `unit` - date unit to use.
  Returns:
    The value of the lowest visible tick on the axis.

### calculateHighestVisibleTickValue

    public java.util.Date calculateHighestVisibleTickValue(DateTickUnit unit)

  Calculates the value of the highest visible tick on the axis.

  Parameters:
    `unit` - date unit to use.
  Returns:
    The value of the highest visible tick on the axis.

### previousStandardDate

    protected java.util.Date previousStandardDate(java.util.Date date,
                                                  DateTickUnit unit)

  Returns the previous "standard" date, for a given date and tick unit.

  Parameters:
    `date` - the reference date.
    `unit` - the tick unit.
  Returns:
    The previous "standard" date.

### nextStandardDate

    protected java.util.Date nextStandardDate(java.util.Date date,
                                              DateTickUnit unit)

  Returns the first "standard" date (based on the specified field and units).

  Parameters:
    `date` - the reference date.
    `unit` - the date tick unit.
  Returns:
    The next "standard" date.

### createStandardDateTickUnits

    public static TickUnitSource createStandardDateTickUnits()

  Returns a collection of standard date tick units that uses the default time zone. This collection will be used by default, but you are free to create your own collection if you want to (see the `ValueAxis.setStandardTickUnits(TickUnitSource)` method inherited from the `ValueAxis` class).

  Returns:
    A collection of standard date tick units.

### createStandardDateTickUnits

    public static TickUnitSource createStandardDateTickUnits(java.util.TimeZone zone)

  Returns a collection of standard date tick units. This collection will be used by default, but you are free to create your own collection if you want to (see the `ValueAxis.setStandardTickUnits(TickUnitSource)` method inherited from the `ValueAxis` class).

  Parameters:
    `zone` - the time zone (`null` not permitted).
  Returns:
    A collection of standard date tick units.

### autoAdjustRange

    protected void autoAdjustRange()

  Rescales the axis to ensure that all data is visible.

  Specified by:
    `autoAdjustRange` in class `ValueAxis`

### selectAutoTickUnit

    protected void selectAutoTickUnit(java.awt.Graphics2D g2,
                                      java.awt.geom.Rectangle2D dataArea,
                                      org.jfree.ui.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(java.awt.Graphics2D g2,
                                                java.awt.geom.Rectangle2D dataArea,
                                                org.jfree.ui.RectangleEdge edge)

  Selects an appropriate tick size for the axis. The strategy is to display as many ticks as possible (selected from a collection 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(java.awt.Graphics2D g2,
                                              java.awt.geom.Rectangle2D dataArea,
                                              org.jfree.ui.RectangleEdge edge)

  Selects an appropriate tick size for the axis. The strategy is to display as many ticks as possible (selected from a collection 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 java.util.List refreshTicks(java.awt.Graphics2D g2,
                                       AxisState state,
                                       java.awt.geom.Rectangle2D dataArea,
                                       org.jfree.ui.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 java.util.List refreshTicksHorizontal(java.awt.Graphics2D g2,
                                                    java.awt.geom.Rectangle2D dataArea,
                                                    org.jfree.ui.RectangleEdge edge)

  Recalculates the ticks for the date axis.

  Parameters:
    `g2` - the graphics device.
    `dataArea` - the area in which the data is to be drawn.
    `edge` - the location of the axis.
  Returns:
    A list of ticks.

### refreshTicksVertical

    protected java.util.List refreshTicksVertical(java.awt.Graphics2D g2,
                                                  java.awt.geom.Rectangle2D dataArea,
                                                  org.jfree.ui.RectangleEdge edge)

  Recalculates the ticks for the date axis.

  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.

### draw

    public AxisState draw(java.awt.Graphics2D g2,
                          double cursor,
                          java.awt.geom.Rectangle2D plotArea,
                          java.awt.geom.Rectangle2D dataArea,
                          org.jfree.ui.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`).

### zoomRange

    public void zoomRange(double lowerPercent,
                          double upperPercent)

  Zooms in on the current range.

  Overrides:
    `zoomRange` in class `ValueAxis`
  Parameters:
    `lowerPercent` - the new lower bound.
    `upperPercent` - the new upper bound.

### equals

    public boolean equals(java.lang.Object obj)

  Tests this 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 `java.lang.Object`
  Returns:
    A hash code.

### clone

    public java.lang.Object clone()
                           throws java.lang.CloneNotSupportedException

  Returns a clone of the object.

  Specified by:
    `clone` in interface `org.jfree.util.PublicCloneable`
  Overrides:
    `clone` in class `ValueAxis`
  Returns:
    A clone.
  Throws:
    `java.lang.CloneNotSupportedException` - if some component of the axis does not support cloning.