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Class ncsa.awt.draw.DrawingOperation

java.lang.Object
   |
   +----ncsa.awt.draw.DrawingOperation

public abstract class DrawingOperation

extends Object

implements Marshallable

canvas

A component that will be drawn into for this operation

clickedPoint

A point used as a reference for this operation

plots

A list of drawing primitives

primitiveIndex

The index in the plot vector of the primitive to perform this action on.

react

Indicates when to perform this action

DrawingOperation()

Constructs a null drawing operation

getIndex()

Gets the index in the vector for the primitive we're interested in

getPlots()

getPoint()

Gets where the user clicked.

getReaction()

Gets the reaction value for this operation, which is used to determine when the operation should be performed.

init(Component, Vector)

Initialize this drawing operation with a place to draw and the primitives involved.

locatePrimitive(int, int)

Given a point value (x,y) locate the first primitive on top of the stack that is located at this point: return its index in the Vector

newInstance()

Creates a new instance of this operation In order for a newInstance() method to be called directly (without this routine), the user would have to specify the actual name of the object.

operation()

Abstract method that must be implemented by the subclassed primitive.

setIndex(int)

Sets the index in the vector for the primitive we're interested in

setPlots(Vector)

setPoint(int, int)

Sets the value of where the user clicked for this operation

 protected transient Vector plots

A list of drawing primitives

 protected transient Component canvas

A component that will be drawn into for this operation

 protected transient int react

Indicates when to perform this action

 protected int primitiveIndex

The index in the plot vector of the primitive to perform this action on.

 protected transient Point clickedPoint

A point used as a reference for this operation

 public DrawingOperation()

Constructs a null drawing operation

 public void init(Component canvas,
                  Vector plots)

Initialize this drawing operation with a place to draw and the primitives involved.

Parameters:

canvas - the graphics context

plots - the vector of drawing primitives

 public Vector getPlots()

 public void setPoint(int x,
                      int y)

Sets the value of where the user clicked for this operation

Parameters:

x - the x coordinate

y - the y coordinate

 public final Point getPoint()

Gets where the user clicked.

Returns:

the Point which the user clicked

 public final int getReaction()

Gets the reaction value for this operation, which is used to determine when the operation should be performed.

Returns:

the reaction value (Event.MOUSE_DOWN, Event.MOUSE_UP)

 public void setIndex(int index)

Sets the index in the vector for the primitive we're interested in

Parameters:

index - the primitive index

 public final int getIndex()

Gets the index in the vector for the primitive we're interested in

Returns:

the primtive index

 public int locatePrimitive(int x,
                            int y)

Given a point value (x,y) locate the first primitive on top of the stack that is located at this point: return its index in the Vector

Parameters:

x - the x coordinate

y - the y coordinate

 public DrawingOperation newInstance()

Creates a new instance of this operation In order for a newInstance() method to be called directly (without this routine), the user would have to specify the actual name of the object. Ideally, this would just be by doing something like:

      dp = (DrawingOperation)Class.forName("Grab").newInstance();
 

However, since these routines exist within a package, the user would have to specify a fully qualified package name and object name to create the object. It could end up looking like:

      dp = (DrawingOperation)Class.forName("ncsa.drawing.Grab").newIns
tance();
 

And, if the package ever changed locations, the code in the user application would need to be modified. In order to spare the user this, I created this routine which handles everything internally.

 public abstract DrawingPrimitive operation()

Abstract method that must be implemented by the subclassed primitive.

 public void setPlots(Vector plots)

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