Module platform
Package org.jfree.chart.plot

Class CrosshairState

java.lang.Object
org.jfree.chart.plot.CrosshairState
Direct Known Subclasses:
CategoryCrosshairState, XYCrosshairState
public class CrosshairState extends Object
Maintains state information about crosshairs on a plot between successive calls to the renderer's draw method. This class is used internally by JFreeChart - it is not intended for external use.

  • Constructor Summary

    Constructors
    Constructor
    Description
    CrosshairState()
    Creates a new crosshairState instance that calculates distance in Java2D space.
    CrosshairState(boolean calculateDistanceInDataSpace)
    Creates a new crosshairState instance.

  • Method Summary

    Modifier and Type
    Method
    Description
    Point2D
    getAnchor()
    Returns the anchor point.
    double
    getAnchorX()
    Returns the x-coordinate (in data space) for the anchor point.
    double
    getAnchorY()
    Returns the y-coordinate (in data space) for the anchor point.
    double
    getCrosshairDistance()
    Returns the distance between the anchor point and the current crosshair point.
    double
    getCrosshairX()
    Get the x-value for the crosshair point.
    double
    getCrosshairY()
    Get the y-value for the crosshair point.
    int
    getDatasetIndex()
    Returns the dataset index that the crosshair values relate to.
    void
    setAnchor(Point2D anchor)
    Sets the anchor point.
    void
    setAnchorX(double x)
    Sets the x-coordinate (in data space) for the anchor point.
    void
    setAnchorY(double y)
    Sets the y-coordinate (in data space) for the anchor point.
    void
    setCrosshairDistance(double distance)
    Sets the distance between the anchor point and the current crosshair point.
    void
    setCrosshairX(double x)
    Sets the x coordinate for the crosshair.
    void
    setCrosshairY(double y)
    Sets the y coordinate for the crosshair.
    void
    setDatasetIndex(int index)
    Sets the dataset index that the current crosshair values relate to.
    void
    updateCrosshairPoint(double x, double y, int datasetIndex, double transX, double transY, PlotOrientation orientation)
    Updates the crosshair point.
    void
    updateCrosshairX(double x, double transX, int datasetIndex)
    Checks to see if the specified data point is the closest to the anchor point and, if yes, updates the current state.
    void
    updateCrosshairY(double candidateY, double transY, int datasetIndex)
    Evaluates a y-value and if it is the closest to the anchor y-value it becomes the new crosshair value.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • CrosshairState

      public CrosshairState()
      Creates a new crosshairState instance that calculates distance in Java2D space.

    • CrosshairState

      public CrosshairState(boolean calculateDistanceInDataSpace)
      Creates a new crosshairState instance. Determination of the data point nearest the anchor point can be calculated in either dataspace or Java2D space. The former should only be used for charts with a single set of axes.
      Parameters:
      calculateDistanceInDataSpace - a flag that controls whether the distance is calculated in data space or Java2D space.

  • Method Details

    • getCrosshairDistance

      public double getCrosshairDistance()
      Returns the distance between the anchor point and the current crosshair point.
      Returns:
      The distance.
      See Also:

    • setCrosshairDistance

      public void setCrosshairDistance(double distance)
      Sets the distance between the anchor point and the current crosshair point. As each data point is processed, its distance to the anchor point is compared with this value and, if it is closer, the data point becomes the new crosshair point.
      Parameters:
      distance - the distance.
      See Also:

    • updateCrosshairPoint

      public void updateCrosshairPoint(double x, double y, int datasetIndex, double transX, double transY, PlotOrientation orientation)
      Updates the crosshair point.
      Parameters:
      x - the x-value.
      y - the y-value.
      datasetIndex - the dataset index.
      transX - the x-value in Java2D space.
      transY - the y-value in Java2D space.
      orientation - the plot orientation (null not permitted).

    • updateCrosshairX

      public void updateCrosshairX(double x, double transX, int datasetIndex)
      Checks to see if the specified data point is the closest to the anchor point and, if yes, updates the current state.
      Parameters:
      x - the x-value.
      transX - the x-value in Java2D space.
      datasetIndex - the dataset index.

    • updateCrosshairY

      public void updateCrosshairY(double candidateY, double transY, int datasetIndex)
      Evaluates a y-value and if it is the closest to the anchor y-value it becomes the new crosshair value.

      Used in cases where only the y-axis is numerical.

      Parameters:
      candidateY - y position of the candidate for the new crosshair point.
      transY - the y-value in Java2D space.
      datasetIndex - the index of the range axis for this y-value.

    • getAnchor

      public Point2D getAnchor()
      Returns the anchor point.
      Returns:
      The anchor point.
      See Also:

    • setAnchor

      public void setAnchor(Point2D anchor)
      Sets the anchor point. This is usually the mouse click point in a chart panel, and the crosshair point will often be the data item that is closest to the anchor point.

      Note that the x and y coordinates (in data space) are not updated by this method - the caller is responsible for ensuring that this happens in sync.
      Parameters:
      anchor - the anchor point (null permitted).
      See Also:

    • getAnchorX

      public double getAnchorX()
      Returns the x-coordinate (in data space) for the anchor point.
      Returns:
      The x-coordinate of the anchor point.

    • setAnchorX

      public void setAnchorX(double x)
      Sets the x-coordinate (in data space) for the anchor point. Note that this does NOT update the anchor itself - the caller is responsible for ensuring this is done in sync.
      Parameters:
      x - the x-coordinate.

    • getAnchorY

      public double getAnchorY()
      Returns the y-coordinate (in data space) for the anchor point.
      Returns:
      The y-coordinate of teh anchor point.

    • setAnchorY

      public void setAnchorY(double y)
      Sets the y-coordinate (in data space) for the anchor point. Note that this does NOT update the anchor itself - the caller is responsible for ensuring this is done in sync.
      Parameters:
      y - the y-coordinate.

    • getCrosshairX

      public double getCrosshairX()
      Get the x-value for the crosshair point.
      Returns:
      The x position of the crosshair point.
      See Also:

    • setCrosshairX

      public void setCrosshairX(double x)
      Sets the x coordinate for the crosshair. This is the coordinate in data space measured against the domain axis.
      Parameters:
      x - the coordinate.
      See Also:

    • getCrosshairY

      public double getCrosshairY()
      Get the y-value for the crosshair point. This is the coordinate in data space measured against the range axis.
      Returns:
      The y position of the crosshair point.
      See Also:

    • setCrosshairY

      public void setCrosshairY(double y)
      Sets the y coordinate for the crosshair.
      Parameters:
      y - the y coordinate.
      See Also:

    • getDatasetIndex

      public int getDatasetIndex()
      Returns the dataset index that the crosshair values relate to. The dataset is mapped to specific axes, and this is how the crosshairs are mapped also.
      Returns:
      The dataset index.
      See Also:

    • setDatasetIndex

      public void setDatasetIndex(int index)
      Sets the dataset index that the current crosshair values relate to.
      Parameters:
      index - the dataset index.
      See Also: