This class is effectively the controller class for the calculator. More...

Collaboration diagram for jscicalc.CalculatorApplet:

Public Member Functions
	CalculatorApplet (String args[])
	Constructor.
void	init ()
	Used to construct the applet.
void	setup ()
	This sets up the calculator for either the applet of the standalone application.
void	clearHistory ()
	As you might expect this clears the calculator history.
void	upHistory ()
	Moves up the history list (if possible).
boolean	downHistory ()
	Moves down the history list (if possible).
void	pushHistory ()
	This is called by EqualsButton and its subclasses and stores an expression in the history list before evaluating it.
void	right ()
	Moves right through the current expression.
void	left ()
	Moves left through the current expression.
javax.swing.Action	backward ()
	This was an experimental feature that I couldn’t get to work.
void	newExpression ()
	When we evaluate an expression, we need to create a new one.
DisplayPanel	displayPanel ()
	Designed so that CalculatorPanel and its subclasses can use the displayPanel object as required.
void	clear ()
	We use this when we want to clear the expresion in the LCD window.
void	delete ()
	Delete at the current caret position.
void	copy ()
	Copy from displayPanel to system clipboard.
void	insert (PObject p)
	Insert at the current caret position.
void	updateDisplay (boolean entry, boolean extra)
	Used to tell the view that we want the display changed, for example, in response to pressing the shift button.
int	displayHeight (int minSize)
	Find the display height at minSize.
int	buttonHeight (int minSize)
	Find the button height at minSize.
int	buttonWidth (int minSize)
	Find the button width at minSize.
int	strutSize (int minSize)
	Find the strut size at minSize.
int	displayHeight ()
	The height of the LCD display in pixels.
int	buttonHeight ()
	The height of a standard button.
int	buttonWidth ()
	The width of a standard button.
int	strutSize ()
	If you look at the CalculatorPanel objects, you’ll see that the buttons are grouped.
void	setMinSize (int mSize)
	An important little function.
int	minSize ()
	If you look at the CalculatorPanel objects, you’ll see that there’s a minimum gap between most objects.
float	buttonTextSize ()
	Get the size of text to use on buttons.
float	entryTextSize ()
	Get the size of text to use on the EntryLabel object.
float	displayTextSize ()
	Get the size of text to use on the DisplayPanel.This reports the size of text for calculator ‘output’.
float	extraTextSize ()
	Get the size of small text to use on the DisplayPanel object.
void	setShift (boolean value)
	Set the shift button to pressed or unpressed.
void	setOn (boolean value)
	Called when we set the calculator on or off.
boolean	getOn ()
	Tells us if the calculator is switched on.
boolean	getShift ()
	Tells us if the shift button is down.
Parser	getParser ()
	The Parser class is the model that this class controls.
OObject	getValue ()
	This is used internally, but it’s also useful if you want to use the calculator as part of something else.
void	setValue (OObject o)
	when an EqualsButton calculates a value it has to transfer it from the Parser object to this and setValue() is the function we use.
void	setMemory (OObject o)
	The calculator can store one value and this is how we do it.
OObject	getMemory ()
void	setAngleType (AngleType angleType)
	We can work with degrees or radians and this is how we set them.
AngleType	getAngleType ()
boolean	getStat ()
void	setStat (boolean stat)
	Set stat mode on or off.
int	getMode ()
	As you’d expect for something emulating a real calculator, we’d better have a mode button.
void	setMode (int i)
	Sets the mode.
void	setMode (PObject p)
	Sets the mode.
void	clearStatMemory ()
	Clear statistical memory.
Complex	statAdd (Complex d)
	Add a Complex to statistical memory.
Complex	statSub (Complex d)
	Removes a Complex from statistical memory.
Mean	statMean ()
	Calculate the mean value.
Complex	statSumSquares ()
	Calculate sum of squares - used in standard deviation/variance calculations.
StDev	statSampleStDev ()
	Calculate the sample standard deviation.
PopStDev	statPopulationStDev ()
	Calculate the population standard deviation.
void	frame (javax.swing.JFrame jframe)
	Used to set value of jframe.
javax.swing.JFrame	frame ()
	Another function whose purpose eludes me.
void	keyPressed (java.awt.event.KeyEvent keyEvent)
	Some keys don’t generate keyTyped Events.
void	keyReleased (java.awt.event.KeyEvent keyEvent)
	Some keys don’t generate keyTyped Events.
void	keyTyped (java.awt.event.KeyEvent keyEvent)
	Handle typed keys.
Base	getBase ()
	We work in various bases.
void	setBase (Base b)
	This is where we set the base.
void	setTextComponent (javax.swing.text.JTextComponent textComponent)
	This function is useful if you want to attach a JTextComponent such as JTextField to the calculator so that when you calculate a value, it gets transferred to the JTextComponent.
final javax.swing.text.JTextComponent	getTextComponent ()
	Get the JTextComponent associated with this oject.
Notation	getNotation ()
	Get notation (scientific, polar, complex).
void	setNotation (Notation notation)
	Set notation (scientific, polar, complex).
final java.awt.Insets	getFrameInsets ()
	Get the frame Insets.
int	graphHeight ()
	Get height for Graph.
int	getSizesSize ()
	Get the value of sizes.size().
int	getMinSize ()
	Get the value of minimumSize.
boolean	getGraphical ()
	Get whether calculator is graphical or not.
void	displayGraph ()
	Display a graph;.
Static Public Member Functions
static void	main (final String args[])
	Use this to construct a calculator.
static javax.swing.JFrame	createFrame (final String args[])
	Actually create a JFrame so that forby using this as an applet, we can use it as a standalone application.
Protected Attributes
javax.swing.JFrame	jframe
	Used by CalcButtonApplet and DisplayPanel.
Package Attributes
HistoryItem	tempParserList
	If we roll up the history with a half completed expression, we can change our minds and go back to it.
int	historyPosition
	where are we in the history list.
Private Member Functions
void	setPanels ()
	The calculator buttons are all set on objects of class CalculatorPanel.
void	setCalculatorPanel (SpecialButtonType sbt)
	Choose a CalculatorPanel.
double	statSize ()
	Used internally in calculations of mean and standard deviation so that we can get these right even when we’ve removed a number.
int	getFrameWidth (int mSize)
	Estimate width of panel at given size.
int	getFrameHeight (int mSize)
	Estimate height of panel at given size.
void	setSizes ()
	Set the allowable range of sizes for the calulator.
void	setGraphical (boolean g)
	Set whether calculator is graphical.
void	setCaretToEntry ()
	Set Caret to entry.
void	setCaretToDisplay ()
	Set Caret to display.
Static Private Member Functions
static void	showFrame (final String args[])
	Shows the frame.
static javax.swing.Spring	scale (javax.swing.Spring spring, int s)
	javax.swing.Spring doesn’t have a scale function.
Private Attributes
jscicalc.graph.Graph	graph
	A graph.
OObject	value
	The value of the last expression evaluated.
AngleType	angleType
	DEGREES or RADIANS.
int	mode
	The MODE.
boolean	stat
	Statistics mode or not.
OObject	memory
	The calculator’s memory.
java.util.Vector< Complex >	statMemory
	Statistics memory needs to hold multiple values.
java.util.Vector< Complex >	statMemoryNeg
	Statistics memory needs to know if you’ve removed values.
int	frameHeight
	The frame height - I think this is redundant because the frame calculates its own height using pack().
CalculatorApplet	applet
	If we create a frame, we create an applet, otherwise, this.
DisplayPanel	displayPanel
	The view object.
CalculatorPanel	calculatorPanel
	The object that contains all the buttons: the input object.
java.util.HashMap < SpecialButtonType, CalculatorPanel >	calculatorPanels
	More than one input panel so keep track of all of them with an map and enumerated type.
int	mSize
	The parameter that determines how much everything is scaled.
Parser	parser
	The model object.
boolean	shift
	Is shift button pressed?
java.util.Vector< HistoryItem >	history
	The history.
boolean	shiftDown
	Used to tell if a modifier key is being held down for shift—I don’t think it actually does anything at the moment.
Notation	notation
	Notation.
javax.swing.text.JTextComponent	textComponent
	Can be used to attach a text component to the object.
DataTransfer	dataTransfer
	Used to Paste from DisplayPanel to system clipboard.
final int	minimumSize = 3
	The minimum value of msize.
java.util.Vector< Integer >	sizes
	The range of sizes allowed.
boolean	graphical
	Used to indicate whether the calculator should be graphical.
Static Private Attributes
static final int	bWidth = 23
	Button width.
static final int	bHeight = 10
	Button width.
static final int	sSize = 3
	Strut size.
static final int	dHeight = 30
	Height of DisplayPanel.
static final float	bTextSize = 4
	Button text size.
static final float	eTextSize = (float)6.4
	EntryPanel text size.
static final float	dTextSize = (float)9.2
	DisplayLabel text size.
static final float	sTextSize = (float)2.5
	Small text size.
static final int	HISTORY_SIZE = 24
	How many events should we store? Change this to suit yourself.
static final java.awt.Color	panelColour = java.awt.Color.LIGHT_GRAY
	This is where you change the DisplayPanel colour.
static final long	serialVersionUID = 1L

Detailed Description

This class is effectively the controller class for the calculator.

It creates either a frame or an applet with the calculator in it, stores the results of calculations, a history of calculations done and the state of the calculator. Parser model class, in the sense that it stores and evaluates the current expression. The view of the current expression is handled by DisplayPanel and the classes it contains.

If you want to use the calculator as a convenient dialog for calculating values for some JTextComponent, then attach the component with setTextComponent() and detach it if necessary with setTextComponent( null ).

Author:: J. D. Lamb

Version:

Revision:: 1.18

Constructor & Destructor Documentation

jscicalc.CalculatorApplet.CalculatorApplet ( String args[] )

Constructor.

This is the constructor we use for the applet.

Parameters:

args

Acceps -g argument for graphical calculator

References jscicalc.CalculatorApplet.applet, and jscicalc.CalculatorApplet.setGraphical().

Referenced by jscicalc.CalculatorApplet.createFrame().

Member Function Documentation

javax.swing.Action jscicalc.CalculatorApplet.backward ( )

This was an experimental feature that I couldn’t get to work.

probably it could be removed.

Returns:: An Action

References jscicalc.DisplayPanel.backward(), and jscicalc.CalculatorApplet.displayPanel().

int jscicalc.CalculatorApplet.buttonHeight ( int minSize )

Find the button height at minSize.

Parameters:

minSize

The minimum size used in the display

Returns:: The button height at minSize

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.bHeight.

Referenced by jscicalc.CalculatorPanel.layoutSprings().

int jscicalc.CalculatorApplet.buttonHeight ( )

The height of a standard button.

Used by CalculatorPanel objects.

Returns:: Desired height of a standard button.

See also:: CalculatorButton

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.minSize().

Referenced by jscicalc.CalculatorApplet.getFrameHeight().

float jscicalc.CalculatorApplet.buttonTextSize ( )

Get the size of text to use on buttons.

Returns:: Desired fontsize for buttons

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.bTextSize, and jscicalc.CalculatorApplet.mSize.

int jscicalc.CalculatorApplet.buttonWidth ( int minSize )

Find the button width at minSize.

Parameters:

minSize

The minimum size used in the display

Returns:: The button width at minSize

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.bWidth.

Referenced by jscicalc.CalculatorPanel.layoutSprings().

int jscicalc.CalculatorApplet.buttonWidth ( )

The width of a standard button.

Used by CalculatorPanel objects.

Returns:: Desired width of a standard button.

See also:: CalculatorButton

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.minSize().

Referenced by jscicalc.CalculatorApplet.getFrameWidth().

void jscicalc.CalculatorApplet.clear ( )

We use this when we want to clear the expresion in the LCD window.

As usual we delegate this to the view class. The expression doesn’t get cleared until we start typing a new one, which is why we separate this from newexpression().

See also:: DisplayPanel; newExpression()

References jscicalc.DisplayPanel.clear(), jscicalc.CalculatorApplet.displayPanel(), jscicalc.CalculatorApplet.getParser(), jscicalc.CalculatorApplet.parser, and jscicalc.DisplayPanel.setExpression().

Referenced by jscicalc.button.OnButton.actionPerformed().

void jscicalc.CalculatorApplet.clearHistory ( )

As you might expect this clears the calculator history.

The only time we use this is when we switch the calculator off. Otherwise we keep a record of the last few expressions together with information about the calculator state (base, degrees or radians, etc.).

References jscicalc.CalculatorApplet.history, and jscicalc.CalculatorApplet.historyPosition.

Referenced by jscicalc.button.OffButton.actionPerformed().

void jscicalc.CalculatorApplet.clearStatMemory ( )

Clear statistical memory.

See also:: SclButton

References jscicalc.CalculatorApplet.statMemory, and jscicalc.CalculatorApplet.statMemoryNeg.

Referenced by jscicalc.button.SclButton.actionPerformed().

void jscicalc.CalculatorApplet.copy ( )

Copy from displayPanel to system clipboard.

References jscicalc.DataTransfer.copy(), and jscicalc.CalculatorApplet.dataTransfer.

Referenced by jscicalc.button.CopyButton.actionPerformed(), and jscicalc.CalculatorApplet.keyPressed().

static javax.swing.JFrame jscicalc.CalculatorApplet.createFrame ( final String args[] ) [static]

Actually create a JFrame so that forby using this as an applet, we can use it as a standalone application.

Like init(), this uses setup() to do most of the real work. Additionally it prints out a boilerplate copyright message.

Parameters:

args

Acceps -g argument for graphical calculator

Returns:: A JFrame with the calculator in it

See also:: init(); main( String[] ); showFrame()

References jscicalc.CalculatorApplet.CalculatorApplet(), jscicalc.CalculatorApplet.frame(), jscicalc.CalculatorApplet.main(), and jscicalc.CalculatorApplet.setup().

Referenced by jscicalc.CalculatorApplet.showFrame().

void jscicalc.CalculatorApplet.delete ( )

Delete at the current caret position.

Delegated to DisplayPanel.

See also:: DisplayPanel

References jscicalc.DisplayPanel.delete(), jscicalc.CalculatorApplet.displayPanel(), and jscicalc.CalculatorApplet.getParser().

Referenced by jscicalc.button.DelButton.actionPerformed().

void jscicalc.CalculatorApplet.displayGraph ( )

Display a graph;.

References jscicalc.CalculatorApplet.getValue(), and jscicalc.CalculatorApplet.graph.

Referenced by jscicalc.button.GraphButton.actionPerformed().

int jscicalc.CalculatorApplet.displayHeight ( int minSize )

Find the display height at minSize.

Parameters:

minSize

The minimum size used in the display

Returns:: The display height at minSize

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.dHeight.

Referenced by jscicalc.CalculatorPanel.layoutSprings().

int jscicalc.CalculatorApplet.displayHeight ( )

The height of the LCD display in pixels.

Used so that the view can get this information.

Returns:: Desired height of DisplayPanel in pixels.

See also:: DisplayPanel

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.minSize().

Referenced by jscicalc.CalculatorApplet.getFrameHeight().

DisplayPanel jscicalc.CalculatorApplet.displayPanel ( )

Designed so that CalculatorPanel and its subclasses can use the displayPanel object as required.

Returns:: The displayPanel

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.displayPanel.

float jscicalc.CalculatorApplet.displayTextSize ( )

Get the size of text to use on the DisplayPanel.This reports the size of text for calculator ‘output’.

Returns:: Desired fontsize for calculator display

See also:: DisplayPanel

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.dTextSize, and jscicalc.CalculatorApplet.mSize.

boolean jscicalc.CalculatorApplet.downHistory ( )

Moves down the history list (if possible).

See also:: upHistory(); DownButton

Returns:: true if any action is performed, false otherwise.

float jscicalc.CalculatorApplet.entryTextSize ( )

Get the size of text to use on the EntryLabel object.

This is the bit of the DisplayPanel object that’s responsible for showing the current expression.

Returns:: Desired fontsize for the EntryLabel object.

See also:: EntryLabel; DisplayPanel

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.eTextSize, and jscicalc.CalculatorApplet.mSize.

float jscicalc.CalculatorApplet.extraTextSize ( )

Get the size of small text to use on the DisplayPanel object.

Small text is for things like “stat”, “radians”, “shift” and the like

Returns:: Desired fontsize for small text

See also:: DisplayPanel

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.mSize, and jscicalc.CalculatorApplet.sTextSize.

void jscicalc.CalculatorApplet.frame ( javax.swing.JFrame jframe )

Used to set value of jframe.

I can’t remember why we need this, possibly for CalcButtonApplet.

Parameters:

jframe

A JFrame

References jscicalc.CalculatorApplet.jframe.

Referenced by jscicalc.CalculatorApplet.createFrame().

javax.swing.JFrame jscicalc.CalculatorApplet.frame ( )

Another function whose purpose eludes me.

Returns:: The frame used to hold the calculator

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.jframe.

Referenced by jscicalc.CalculatorApplet.createFrame(), jscicalc.CalculatorApplet.init(), jscicalc.CalculatorApplet.setMinSize(), jscicalc.CalculatorApplet.setMode(), and jscicalc.CalculatorApplet.showFrame().

AngleType jscicalc.CalculatorApplet.getAngleType ( )

Returns:: Angletype: degrees or radians.

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.angleType.

Referenced by jscicalc.button.CalculatorButton.actionPerformed(), jscicalc.DataTransfer.copy(), jscicalc.CalculatorApplet.downHistory(), jscicalc.CalculatorApplet.pushHistory(), jscicalc.CalculatorApplet.setup(), and jscicalc.CalculatorApplet.upHistory().

Base jscicalc.CalculatorApplet.getBase ( )

We work in various bases.

Although numbers are always stored as doubles (i.e. IEE double precision floating point binary representations) so that the Base is essentially just used for formatting and so mainly used by the view, we need to keep a record of base and this is a natural place to keep it, and the Parser object needs to know the base so that it parses numbers entered correctly.

Returns:: The base (default is Base.DECIMAL)

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.Parser.base, and jscicalc.CalculatorApplet.parser.

Referenced by jscicalc.DataTransfer.copy(), jscicalc.CalculatorApplet.downHistory(), jscicalc.CalculatorApplet.pushHistory(), jscicalc.CalculatorApplet.setBase(), jscicalc.CalculatorApplet.setShift(), jscicalc.CalculatorApplet.setup(), and jscicalc.CalculatorApplet.upHistory().

int jscicalc.CalculatorApplet.getFrameHeight ( int mSize ) [private]

Estimate height of panel at given size.

Parameters:

mSize

The size at which to estimate width

Returns:: An estimate (usually correct) of current frame height at given size

References jscicalc.CalculatorApplet.buttonHeight(), jscicalc.CalculatorApplet.displayHeight(), jscicalc.CalculatorApplet.getFrameInsets(), and jscicalc.CalculatorApplet.strutSize().

Referenced by jscicalc.CalculatorApplet.graphHeight(), and jscicalc.CalculatorApplet.setSizes().

final java.awt.Insets jscicalc.CalculatorApplet.getFrameInsets ( )

Get the frame Insets.

Returns:: frame Insets

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.jframe.

Referenced by jscicalc.CalculatorApplet.getFrameHeight(), and jscicalc.CalculatorApplet.getFrameWidth().

int jscicalc.CalculatorApplet.getFrameWidth ( int mSize ) [private]

Estimate width of panel at given size.

Parameters:

mSize

The size at which to estimate wdith

Returns:: An estimate (usually correct) of current frame width at given size

References jscicalc.CalculatorApplet.buttonWidth(), jscicalc.CalculatorApplet.getFrameInsets(), and jscicalc.CalculatorApplet.strutSize().

Referenced by jscicalc.CalculatorApplet.setSizes().

boolean jscicalc.CalculatorApplet.getGraphical ( )

Get whether calculator is graphical or not.

Returns:: true or false according as calculator graphical or not

References jscicalc.CalculatorApplet.graphical.

Referenced by jscicalc.ShiftPanel.setButtons(), jscicalc.PlainPanel.setButtons(), and jscicalc.CalculatorPanel.setUp().

OObject jscicalc.CalculatorApplet.getMemory ( )

Returns:: value from memory.

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.memory.

Referenced by jscicalc.button.MplusButton.actionPerformed(), and jscicalc.button.MminusButton.actionPerformed().

int jscicalc.CalculatorApplet.getMinSize ( )

Get the value of minimumSize.

Returns:: the value of minimumSize

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.minimumSize.

int jscicalc.CalculatorApplet.getMode ( )

As you’d expect for something emulating a real calculator, we’d better have a mode button.

This one uses integers rather than enumerated types and you get the current mode with this function.

Returns:: The mode (currently 1, 2 or 3 or maybe 4)

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.mode.

Notation jscicalc.CalculatorApplet.getNotation ( )

Get notation (scientific, polar, complex).

Returns:: the notation.

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.notation.

Referenced by jscicalc.button.SciButton.actionPerformed(), jscicalc.button.PolButton.actionPerformed(), jscicalc.button.CplxButton.actionPerformed(), jscicalc.CalculatorApplet.downHistory(), jscicalc.CalculatorApplet.pushHistory(), jscicalc.CalculatorApplet.setup(), and jscicalc.CalculatorApplet.upHistory().

boolean jscicalc.CalculatorApplet.getOn ( )

Tells us if the calculator is switched on.

This is useful in view classes because only this class gets to control such information.

Returns:: true or false according as the calculator is on or off

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.displayPanel(), and jscicalc.DisplayPanel.getOn().

Referenced by jscicalc.button.ModeButton.actionPerformed().

Parser jscicalc.CalculatorApplet.getParser ( )

The Parser class is the model that this class controls.

When required, for example, so that we can create a view of the current expression, we use this function to make the Parser object accessible. Ideally it would be final, but it’s convenient to allow CalculatorButton objects to modify the Parser object directly.

Returns:: The Parser object

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.parser.

Referenced by jscicalc.button.STOButton.actionPerformed(), jscicalc.button.SplusButton.actionPerformed(), jscicalc.button.SminusButton.actionPerformed(), jscicalc.button.MplusButton.actionPerformed(), jscicalc.button.MminusButton.actionPerformed(), jscicalc.button.EqualsButton.actionPerformed(), jscicalc.CalculatorApplet.clear(), jscicalc.CalculatorApplet.delete(), and jscicalc.CalculatorApplet.insert().

boolean jscicalc.CalculatorApplet.getShift ( )

Tells us if the shift button is down.

Returns:: true or false according as the shift button is down or up

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.shift.

Referenced by jscicalc.CalculatorApplet.setStat().

int jscicalc.CalculatorApplet.getSizesSize ( )

Get the value of sizes.size().

Returns:: the value of sizes.size()

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.sizes.

boolean jscicalc.CalculatorApplet.getStat ( )

Returns:: true or false according as we are in statistics mode or not.

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.stat.

final javax.swing.text.JTextComponent jscicalc.CalculatorApplet.getTextComponent ( )

Get the JTextComponent associated with this oject.

This feature is only useful if you want to attach the calculator to a component, for example to calculate some number for you.

Returns:: The component attached

References jscicalc.CalculatorApplet.textComponent.

OObject jscicalc.CalculatorApplet.getValue ( )

This is used internally, but it’s also useful if you want to use the calculator as part of something else.

In fact, the calculator was really originally designed because I couldn’t find a calculator applet that emulated the statistical functions on a standard calculator. So it was really just a part of a bigger applet that made confidence intervals. This function was put in the calculator specifically to allow external access to the calculated value, which when it changed would be transferred to a JTextField on another part of the applet.

Returns:: The value, which should be a Double

See also:: Parser

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.value.

Referenced by jscicalc.button.STOButton.actionPerformed(), jscicalc.button.SplusButton.actionPerformed(), jscicalc.button.SminusButton.actionPerformed(), jscicalc.button.MplusButton.actionPerformed(), jscicalc.button.MminusButton.actionPerformed(), jscicalc.button.EqualsButton.actionPerformed(), jscicalc.button.CalculatorButton.add(), jscicalc.DataTransfer.copy(), jscicalc.CalculatorApplet.displayGraph(), jscicalc.CalculatorApplet.updateDisplay(), and jscicalc.CalculatorApplet.upHistory().

int jscicalc.CalculatorApplet.graphHeight ( )

Get height for Graph.

Returns:: A height

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.getFrameHeight(), jscicalc.CalculatorApplet.jframe, and jscicalc.CalculatorApplet.mSize.

void jscicalc.CalculatorApplet.init ( )

Used to construct the applet.

Calls setup to do most of the work.

See also:: setup()

References jscicalc.CalculatorApplet.applet, jscicalc.CalculatorApplet.frame(), and jscicalc.CalculatorApplet.setup().

void jscicalc.CalculatorApplet.insert ( PObject p )

Insert at the current caret position.

Delegated to DisplayPanel.

Parameters:

p

The PObject representing whatever we’re trying to insert

See also:: DisplayPanel

References jscicalc.CalculatorApplet.displayPanel(), jscicalc.CalculatorApplet.getParser(), and jscicalc.DisplayPanel.insert().

Referenced by jscicalc.button.STOButton.actionPerformed(), jscicalc.button.SplusButton.actionPerformed(), jscicalc.button.SminusButton.actionPerformed(), jscicalc.button.MplusButton.actionPerformed(), jscicalc.button.MminusButton.actionPerformed(), jscicalc.button.EqualsButton.actionPerformed(), and jscicalc.button.CalculatorButton.add().

void jscicalc.CalculatorApplet.keyPressed ( java.awt.event.KeyEvent keyEvent )

Some keys don’t generate keyTyped Events.

This function handles the arrow keys.

Parameters:

keyEvent

The event of key pressed

References jscicalc.CalculatorPanel.buttons, jscicalc.CalculatorApplet.calculatorPanel, jscicalc.CalculatorApplet.copy(), and jscicalc.CalculatorApplet.shiftDown.

void jscicalc.CalculatorApplet.keyReleased ( java.awt.event.KeyEvent keyEvent )

Some keys don’t generate keyTyped Events.

This function handles the release of the AltGraph key associated with the shift button. As far as I can tell Java 2 doesn’t actually generate an event with this key; so this part of the function is probably redundant. I’ve also implemented a crude hack here to recognise when CTRL-C is pressed and generate a copy-to-clipboard event.

Parameters:

keyEvent

The event of key pressed

References jscicalc.DataTransfer.copy(), jscicalc.CalculatorApplet.dataTransfer, and jscicalc.CalculatorApplet.shiftDown.

void jscicalc.CalculatorApplet.keyTyped ( java.awt.event.KeyEvent keyEvent )

Handle typed keys.

This is how we associate keys to buttons. There are too many buttons to ask each to handle its own (and too much risk of confusion); so we handle them together from a list of buttons generated by CalculatorPanel.

Generally this function just finds which key you typed and uses a map to activate the appropriate button.

Parameters:

keyEvent

The event of key typed

See also:: CalculatorPanel.keyMap()

References jscicalc.button.CalculatorButton.actionPerformed(), jscicalc.CalculatorPanel.buttons, jscicalc.CalculatorApplet.calculatorPanel, jscicalc.CalculatorPanel.keyMap, and jscicalc.CalculatorApplet.shift.

void jscicalc.CalculatorApplet.left ( )

Moves left through the current expression.

We need this so that expressions are editable.

See also:: LeftButton

References jscicalc.CalculatorApplet.displayPanel(), and jscicalc.DisplayPanel.left().

Referenced by jscicalc.button.LeftButton.actionPerformed().

static void jscicalc.CalculatorApplet.main ( final String args[] ) [static]

Use this to construct a calculator.

At the moment the args parameter is completely ignored, though there are some useful possibilities. It would be nice if we could specify the size (minSize) by passing some argument. The MODE button currently allows this and a default is hardcoded.

Parameters:

args

Acceps -g argument for graphical calculator

References jscicalc.CalculatorApplet.showFrame().

Referenced by jscicalc.CalculatorApplet.createFrame().

int jscicalc.CalculatorApplet.minSize ( )

If you look at the CalculatorPanel objects, you’ll see that there’s a minimum gap between most objects.

CalculatorApplet keep control of such things and this function reports them to CalculatorPanel objects when required.

Returns:: Desired size of button-group separation

See also:: CalculatorPanel

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.mSize.

Referenced by jscicalc.CalculatorApplet.buttonHeight(), jscicalc.CalculatorApplet.buttonWidth(), jscicalc.CalculatorApplet.displayHeight(), jscicalc.button.DownButton.DownButton(), jscicalc.button.InfoButton.InfoButton(), jscicalc.CalculatorPanel.layoutSprings(), jscicalc.button.LeftButton.LeftButton(), jscicalc.button.RightButton.RightButton(), jscicalc.CalculatorApplet.setMode(), jscicalc.CalculatorApplet.strutSize(), and jscicalc.button.UpButton.UpButton().

void jscicalc.CalculatorApplet.newExpression ( )

When we evaluate an expression, we need to create a new one.

This function delegates the job to the DisplayPanel.

See also:: DisplayPanel

References jscicalc.CalculatorApplet.displayPanel(), and jscicalc.DisplayPanel.newExpression().

Referenced by jscicalc.button.STOButton.actionPerformed(), jscicalc.button.SplusButton.actionPerformed(), jscicalc.button.SminusButton.actionPerformed(), jscicalc.button.MplusButton.actionPerformed(), jscicalc.button.MminusButton.actionPerformed(), and jscicalc.button.EqualsButton.actionPerformed().

void jscicalc.CalculatorApplet.pushHistory ( )

This is called by EqualsButton and its subclasses and stores an expression in the history list before evaluating it.

This allows the possibility of going back and editing a mistyped expression.

See also:: EqualsButton

References jscicalc.CalculatorApplet.getAngleType(), jscicalc.CalculatorApplet.getBase(), jscicalc.Parser.getList(), jscicalc.CalculatorApplet.getNotation(), jscicalc.CalculatorApplet.history, jscicalc.CalculatorApplet.HISTORY_SIZE, jscicalc.CalculatorApplet.historyPosition, and jscicalc.CalculatorApplet.parser.

Referenced by jscicalc.button.STOButton.actionPerformed(), jscicalc.button.SplusButton.actionPerformed(), jscicalc.button.SminusButton.actionPerformed(), jscicalc.button.MplusButton.actionPerformed(), jscicalc.button.MminusButton.actionPerformed(), and jscicalc.button.EqualsButton.actionPerformed().

void jscicalc.CalculatorApplet.right ( )

Moves right through the current expression.

We need this so that expressions are editable.

See also:: RightButton

References jscicalc.CalculatorApplet.displayPanel(), and jscicalc.DisplayPanel.right().

Referenced by jscicalc.button.RightButton.actionPerformed().

static javax.swing.Spring jscicalc.CalculatorApplet.scale	(	javax.swing.Spring	spring,
		int	s
	)			`[static, private]`

javax.swing.Spring doesn’t have a scale function.

Although we only use this in CalculatorPanel and its derived classes, we define a scale function here. Why? Originally we used this class to generate Springs. It could probably be moved to CalculatorPanel.

Parameters:

	spring	A spring
	s	how much we want to scale the spring: a positive integer - negatives and zero are ignored

See also:: CalculatorPanel

void jscicalc.CalculatorApplet.setAngleType ( AngleType angleType )

We can work with degrees or radians and this is how we set them.

Does anyone use grads? If so you can ay change AngleType etc, to handle. these.

Parameters:

angleType

AngleType.DEGREES or AngleType.RADIANS

See also:: AngleType

Referenced by jscicalc.CalculatorApplet.downHistory(), jscicalc.CalculatorApplet.setMode(), and jscicalc.CalculatorApplet.upHistory().

void jscicalc.CalculatorApplet.setBase ( Base b )

This is where we set the base.

Used by EqualsButton and its derived classed.

Parameters:

b

The base

See also:: EqualsButton; HexButton; BinButton; DecButton; OctButton

References jscicalc.Parser.base, jscicalc.CalculatorApplet.getBase(), jscicalc.CalculatorApplet.parser, and jscicalc.CalculatorApplet.setCalculatorPanel().

Referenced by jscicalc.CalculatorApplet.downHistory(), jscicalc.button.EqualsButton.setBase(), jscicalc.CalculatorApplet.setStat(), jscicalc.CalculatorApplet.setup(), and jscicalc.CalculatorApplet.upHistory().

void jscicalc.CalculatorApplet.setCalculatorPanel ( SpecialButtonType sbt ) [private]

Choose a CalculatorPanel.

You would do this in response to a button press. The most obvious one is the shift button, but we also change panels for Stat mode and when changing base.

Parameters:

sbt

An enumerated type representing the panel we want

References jscicalc.CalculatorApplet.calculatorPanel, jscicalc.CalculatorApplet.calculatorPanels, and jscicalc.CalculatorPanel.setDisplayPanel().

Referenced by jscicalc.CalculatorApplet.setBase(), jscicalc.CalculatorApplet.setPanels(), and jscicalc.CalculatorApplet.setShift().

void jscicalc.CalculatorApplet.setCaretToDisplay ( ) [private]

Set Caret to display.

References jscicalc.CalculatorApplet.displayPanel(), and jscicalc.DisplayPanel.setCaretToDisplay().

Referenced by jscicalc.CalculatorApplet.downHistory().

void jscicalc.CalculatorApplet.setCaretToEntry ( ) [private]

Set Caret to entry.

References jscicalc.CalculatorApplet.displayPanel(), and jscicalc.DisplayPanel.setCaretToEntry().

Referenced by jscicalc.CalculatorApplet.upHistory().

void jscicalc.CalculatorApplet.setGraphical ( boolean g ) [private]

Set whether calculator is graphical.

Parameters:

g

true or false according as you want a graphical calculator

References jscicalc.CalculatorApplet.graphical.

Referenced by jscicalc.CalculatorApplet.CalculatorApplet().

void jscicalc.CalculatorApplet.setMemory ( OObject o )

The calculator can store one value and this is how we do it.

Notice that it allows memory addition and subtraction when used in conjunction with getMemory().

Parameters:

o

The value to put into memory

See also:: getMemory()

References jscicalc.CalculatorApplet.memory.

Referenced by jscicalc.button.STOButton.actionPerformed(), jscicalc.button.MplusButton.actionPerformed(), jscicalc.button.MminusButton.actionPerformed(), and jscicalc.button.MclButton.actionPerformed().

void jscicalc.CalculatorApplet.setMinSize ( int mSize )

An important little function.

This effectively defines the size of the calculator. Values in the range 3-6 seem to work well. The CalculatorApplet object stores this value and uses it to calculate everything else. That way it stays in control of sizes but also allows you to scale the calculator.

Parameters:

mSize

A small integer determining the smallest unit used in drawing the calculator

References jscicalc.CalculatorApplet.frame(), jscicalc.CalculatorApplet.graph, and jscicalc.CalculatorApplet.setPanels().

Referenced by jscicalc.CalculatorApplet.setMode().

void jscicalc.CalculatorApplet.setMode ( int i )

Sets the mode.

Allows us to change from degrees to radians, change calculator size, set STAT mode on or off.

Parameters:

i

The new mode: it’s forced into the right range even if you give an illegal value.

References jscicalc.CalculatorApplet.frame(), jscicalc.CalculatorApplet.mode, and jscicalc.CalculatorApplet.sizes.

void jscicalc.CalculatorApplet.setMode ( PObject p )

Sets the mode.

Allows us to change from degrees to radians, change calculator size, set STAT mode on or off. CalculatorButton objects generate PObjects rather than integers; so we pass these and act accordingly. This is not a particularly good piece of code, but there’s not much that can go seriously wrong with it; so I'm not planning to fix it.

Parameters:

p

A PObject, generated by a Calculator button during change of mode.

References jscicalc.pobject.Numeral.get(), jscicalc.CalculatorApplet.getMode(), jscicalc.CalculatorApplet.minSize(), jscicalc.CalculatorApplet.mode, jscicalc.pobject.Numeral.name(), jscicalc.CalculatorApplet.setAngleType(), jscicalc.CalculatorApplet.setMinSize(), jscicalc.CalculatorApplet.setMode(), jscicalc.CalculatorApplet.setStat(), jscicalc.CalculatorApplet.sizes, and jscicalc.CalculatorApplet.updateDisplay().

void jscicalc.CalculatorApplet.setNotation ( Notation notation )

Set notation (scientific, polar, complex).

Parameters:

notation

The notation to set

Referenced by jscicalc.CalculatorApplet.downHistory(), and jscicalc.CalculatorApplet.upHistory().

void jscicalc.CalculatorApplet.setOn ( boolean value )

Called when we set the calculator on or off.

Parameters:

value

true for on, false for off.

See also:: OnButton; OffButton

References jscicalc.CalculatorApplet.displayPanel(), and jscicalc.DisplayPanel.setOn().

Referenced by jscicalc.button.OnButton.actionPerformed(), jscicalc.button.OffButton.actionPerformed(), and jscicalc.CalculatorApplet.setup().

void jscicalc.CalculatorApplet.setPanels ( ) [private]

The calculator buttons are all set on objects of class CalculatorPanel.

I tried first changing the buttons according to context, but redoing 40 buttons or so every time you press shift slows the calculator down visibly. So this is the alternative. The panels also take some time to generate and so they are created on separate threads. This allows us to see and start using the calculator while some of the panels are still being constructed.

See also:: CalculatorPanel

References jscicalc.CalculatorApplet.calculatorPanel, jscicalc.CalculatorApplet.calculatorPanels, jscicalc.CalculatorPanel.createPanel(), jscicalc.CalculatorApplet.displayPanel(), jscicalc.CalculatorApplet.panelColour, jscicalc.CalculatorApplet.setCalculatorPanel(), and jscicalc.DisplayPanel.setUp().

Referenced by jscicalc.CalculatorApplet.setMinSize(), and jscicalc.CalculatorApplet.setup().

void jscicalc.CalculatorApplet.setShift ( boolean value )

Set the shift button to pressed or unpressed.

Obviously, it will be called by ShiftButton, but it’s also called when a shifted key is pressed and on some other occasions.

Parameters:

value

true or false according as the shift button is pressed or not.

See also:: ShiftButton

References jscicalc.CalculatorApplet.getBase(), jscicalc.CalculatorApplet.setCalculatorPanel(), jscicalc.CalculatorApplet.shift, and jscicalc.CalculatorApplet.stat.

void jscicalc.CalculatorApplet.setSizes ( ) [private]

Set the allowable range of sizes for the calulator.

These are the values that mSize may take.

References jscicalc.CalculatorApplet.getFrameHeight(), jscicalc.CalculatorApplet.getFrameWidth(), jscicalc.CalculatorApplet.jframe, jscicalc.CalculatorApplet.minimumSize, jscicalc.CalculatorApplet.mSize, and jscicalc.CalculatorApplet.sizes.

Referenced by jscicalc.CalculatorApplet.setup().

void jscicalc.CalculatorApplet.setStat ( boolean stat )

Set stat mode on or off.

Parameters:

stat

A value: true for stat mode.

See also:: StatPanel; getStat()

References jscicalc.CalculatorApplet.getShift(), jscicalc.CalculatorApplet.setBase(), and jscicalc.CalculatorApplet.setShift().

Referenced by jscicalc.CalculatorApplet.setMode().

void jscicalc.CalculatorApplet.setTextComponent ( javax.swing.text.JTextComponent textComponent )

This function is useful if you want to attach a JTextComponent such as JTextField to the calculator so that when you calculate a value, it gets transferred to the JTextComponent.

Parameters:

textComponent

The component you want to attach

References jscicalc.CalculatorApplet.textComponent.

Referenced by jscicalc.CalculatorApplet.setup().

void jscicalc.CalculatorApplet.setup ( )

This sets up the calculator for either the applet of the standalone application.

I’m not sure why the function is public because it probably should be private.

Referenced by jscicalc.CalculatorApplet.createFrame(), and jscicalc.CalculatorApplet.init().

void jscicalc.CalculatorApplet.setValue ( OObject o )

when an EqualsButton calculates a value it has to transfer it from the Parser object to this and setValue() is the function we use.

The object should be a Complex, but we can’t represent errors as Complex numbers and it's convenient just to extract what we can as an object and use instanceof to check if needed.

You could modify this function to put a value directly into some other Component. One of the design objectives of the calculator is that you should can use it as part of some applet as a pop up calculator. A better approach might be to use EqualsButton to send the value where you want or to tell the Component to set its value using getValue().

Have a look at CalcButtonApplet if you want to see how you can make the calculator pop up on demand.

Parameters:

o

The value (should be gotten from the Parser Object)

See also:: Parser; EqualsButton; getValue(); CalcButtonApplet

References jscicalc.CalculatorApplet.displayPanel(), jscicalc.DisplayPanel.setValue(), and jscicalc.CalculatorApplet.value.

Referenced by jscicalc.button.STOButton.actionPerformed(), jscicalc.button.SplusButton.actionPerformed(), jscicalc.button.SminusButton.actionPerformed(), jscicalc.button.RCLButton.actionPerformed(), jscicalc.button.OnButton.actionPerformed(), jscicalc.button.MminusButton.actionPerformed(), jscicalc.button.EqualsButton.actionPerformed(), jscicalc.button.AnsButton.actionPerformed(), jscicalc.CalculatorApplet.setup(), and jscicalc.CalculatorApplet.upHistory().

static void jscicalc.CalculatorApplet.showFrame ( final String args[] ) [static, private]

Shows the frame.

This is used by main to make sure the calculator JFrame is created on the event-dispatching thread if we don’t run it as an applet. I haven’t checked that this all works as it should.

Parameters:

args

Acceps -g argument for graphical calculator

References jscicalc.CalculatorApplet.createFrame(), and jscicalc.CalculatorApplet.frame().

Referenced by jscicalc.CalculatorApplet.main().

Complex jscicalc.CalculatorApplet.statAdd ( Complex d )

Add a Complex to statistical memory.

Statistical memory holds a list of these numbers so that mean, standard deviation and the like can be calcualted at will. The function also returns the number of objects in statistical memory as an Object. An object is used because it conveniently fits what we typically want to do with the return result: display it in the calculator where the expression was evaluated.

Parameters:

d

The Complex to put into memory

Returns:: The number of objects in statistical memory.

References jscicalc.CalculatorApplet.statMemory, and jscicalc.CalculatorApplet.statSize().

Mean jscicalc.CalculatorApplet.statMean ( )

Calculate the mean value.

Returns:: The mean value

See also:: Mean

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.complex.Complex.add(), jscicalc.complex.Complex.divide(), jscicalc.pobject.Mean.setError(), jscicalc.pobject.Mean.setValue(), jscicalc.CalculatorApplet.statMemory, jscicalc.CalculatorApplet.statMemoryNeg, jscicalc.CalculatorApplet.statSize(), and jscicalc.complex.Complex.subtract().

Referenced by jscicalc.CalculatorApplet.statSumSquares().

PopStDev jscicalc.CalculatorApplet.statPopulationStDev ( )

Calculate the population standard deviation.

Returns:: The population standard deviation value

See also:: PopStDev

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.complex.Complex.divide(), jscicalc.pobject.PopStDev.setError(), jscicalc.pobject.PopStDev.setValue(), jscicalc.complex.Complex.sqrt(), jscicalc.CalculatorApplet.statSize(), and jscicalc.CalculatorApplet.statSumSquares().

StDev jscicalc.CalculatorApplet.statSampleStDev ( )

Calculate the sample standard deviation.

Returns:: The sample standard deviation value

See also:: StDev

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.complex.Complex.divide(), jscicalc.pobject.StDev.setError(), jscicalc.pobject.StDev.setValue(), jscicalc.complex.Complex.sqrt(), jscicalc.CalculatorApplet.statSize(), and jscicalc.CalculatorApplet.statSumSquares().

double jscicalc.CalculatorApplet.statSize ( ) [private]

Used internally in calculations of mean and standard deviation so that we can get these right even when we’ve removed a number.

Returns:: The number to use in statistical calculations

References jscicalc.CalculatorApplet.statMemory, and jscicalc.CalculatorApplet.statMemoryNeg.

Referenced by jscicalc.CalculatorApplet.statAdd(), jscicalc.CalculatorApplet.statMean(), jscicalc.CalculatorApplet.statPopulationStDev(), jscicalc.CalculatorApplet.statSampleStDev(), and jscicalc.CalculatorApplet.statSub().

Complex jscicalc.CalculatorApplet.statSub ( Complex d )

Removes a Complex from statistical memory.

Parameters:

d

The Complex to put into memory

Returns:: The number of objects in statistcal memory.

See also:: statAdd( Complex )

References jscicalc.CalculatorApplet.statMemoryNeg, and jscicalc.CalculatorApplet.statSize().

Complex jscicalc.CalculatorApplet.statSumSquares ( )

Calculate sum of squares - used in standard deviation/variance calculations.

Returns:: sum of squares of statistical memory values

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.complex.Complex.add(), jscicalc.pobject.Container.error, jscicalc.complex.Complex.square(), jscicalc.CalculatorApplet.statMean(), jscicalc.CalculatorApplet.statMemory, jscicalc.CalculatorApplet.statMemoryNeg, jscicalc.complex.Complex.subtract(), and jscicalc.pobject.Container.value().

Referenced by jscicalc.CalculatorApplet.statPopulationStDev(), and jscicalc.CalculatorApplet.statSampleStDev().

int jscicalc.CalculatorApplet.strutSize ( )

If you look at the CalculatorPanel objects, you’ll see that the buttons are grouped.

This defines the width of the gap between groups. CalculatorApplet keep control of such things and this function reports them to CalculatorPanel objects when required.

Returns:: Desired size of button-group separation

See also:: CalculatorPanel

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.minSize().

Referenced by jscicalc.CalculatorApplet.getFrameHeight(), and jscicalc.CalculatorApplet.getFrameWidth().

int jscicalc.CalculatorApplet.strutSize ( int minSize )

Find the strut size at minSize.

Parameters:

minSize

The minimum size used in the display

Returns:: The strut size at minSize

Implements jscicalc.ReadOnlyCalculatorApplet.

References jscicalc.CalculatorApplet.sSize.

Referenced by jscicalc.CalculatorPanel.layoutSprings().

void jscicalc.CalculatorApplet.updateDisplay	(	boolean	entry,
		boolean	extra
	)

Used to tell the view that we want the display changed, for example, in response to pressing the shift button.

We sometimes want to update the display but not the expression in the EntryLabel object.

Additionally this function will send a copy of the calculated value as a string to any JTextComponent you happen to have attached to the calculator.

Parameters:

	entry	Set to true or false according as we want the entry label updated or not
	extra	Designed so that we can specify whether the ExtraPanel object should be updated, but not currently used

See also:: DisplayPanel; EntryLabel

References jscicalc.CalculatorApplet.displayPanel(), jscicalc.CalculatorApplet.getValue(), jscicalc.CalculatorApplet.textComponent, and jscicalc.DisplayPanel.update().

void jscicalc.CalculatorApplet.upHistory ( )

Moves up the history list (if possible).

CalculatorApplet maintains a list of previously evaluated expressions and this function allows you to move backward through them. It’s called by UpButton and is particularly useful if you want to reedit some expression.