Module org.jfree.chart

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 Detail

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 Detail

getCrosshairDistance

public double getCrosshairDistance()

Returns the distance between the anchor point and the current crosshair point.

Returns:

The distance.

See Also:

setCrosshairDistance(double)

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:

getCrosshairDistance()

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(Point2D)

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:

getAnchor()

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(double)

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:

getCrosshairX(), setCrosshairY(double), updateCrosshairPoint(double, double, int, double, double, PlotOrientation)

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(double)

setCrosshairY

public void setCrosshairY(double y)

Sets the y coordinate for the crosshair.

Parameters:

y - the y coordinate.

See Also:

getCrosshairY(), setCrosshairX(double), updateCrosshairPoint(double, double, int, double, double, PlotOrientation)

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(int)

setDatasetIndex

public void setDatasetIndex(int index)

Sets the dataset index that the current crosshair values relate to.

Parameters:

index - the dataset index.

See Also:

getDatasetIndex()