edu.hws.jcm.awt
Class DataTableInput

java.lang.Object
  |
  +--java.awt.Component
        |
        +--java.awt.Container
              |
              +--java.awt.Panel
                    |
                    +--edu.hws.jcm.awt.DataTableInput

All Implemented Interfaces:

javax.accessibility.Accessible, java.awt.image.ImageObserver, MathObject, java.awt.MenuContainer, ParserExtension, java.io.Serializable

public class DataTableInput

extends java.awt.Panel

implements ParserExtension

A DataTableInput lets the user input a grid of real numbers arranged in rows and columns. Each column has a name, and rows are numberd starting from 1. The column names and row numbers can be displayed, optionally. By default, a new row is added automatically if the user moves down out of the last row by pressing return or down-arrow, provided the last row is non-empty. Rows can also be added programmatically. Columns are usually added in the constructor, but they can also be added later. If the user leaves a cell at a time when the content of that cell does not represent a legal number, then the message "bad input" will be displayed in the cell.

A DataTableInput can be given a name and can then be added to a parser. The parser will then recognize the name of the table. In an expression, the table name can be followed by a ".", then one of the column names from table, then an expression in parentheses. This represents a reference to the number in one of the cells in the table. The expression gives the number of the row, where rows are numbered starting from 1. For example: "data.A(3)" represents the third number in column "A" in a table named data. The table name and "." can also be followed by the word "sum" and an expression in parentheses. An expression used in this way can include references to the column names in the table and to the special value "rowNumber". The value of expression is computed for each row in the table and the sum of the values is computed. In the expression that is being summed, a column name represents the number in that column and rowNumber represents the number of the row. For example: "data.sum(A^2)". Finally, the "." can be followed by the word "count". "count" can, optionally be followed by an empty pair of parentheses. This represents the number of rows. For example: "data.count". Empty rows at the bottom of the table are ignored in both "sum" and "count".

Note that rows are numbered starting from 1 because row numbers can be visible to the user, who shouldn't be subjected to zero-based numbering. However, columns are always numbered from zero.

See Also:

Serialized Form

Inner classes inherited from class java.awt.Panel

java.awt.Panel.AccessibleAWTPanel

Inner classes inherited from class java.awt.Container

java.awt.Container.AccessibleAWTContainer

Inner classes inherited from class java.awt.Component

java.awt.Component.AccessibleAWTComponent

Fields inherited from class java.awt.Component

BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT

Fields inherited from interface java.awt.image.ImageObserver

ABORT, ALLBITS, ERROR, FRAMEBITS, HEIGHT, PROPERTIES, SOMEBITS, WIDTH

Constructor Summary

DataTableInput()
Create a DataTableInput with no columns.

DataTableInput(java.lang.String name, int columns)
Create a table with the specified number of columns, named "A", "B", etc.

DataTableInput(java.lang.String name, java.lang.String[] columnNames)
Create a table with the specified column names.

Method Summary

int	addColumn() Add a column at the right side of the table, with all cells initially empty.
int	addColumn(java.lang.String name) Add a column with the specified name at the right side of the table, with all cells initially empty.
void	addRows(int rowCt) Add the specified number of empty rows at the bottom of the table.
void	addVariablesToParser(Parser p) Add a row number variable (from the getRowNumberVariable() method) and a column variable for each column (from the getColumnVariable() method) to the parser.
void	clear() Remove all rows from the table, leaving just one empty row.
void	deleteCurrentRow() Delete the row that contains the cell that the user is editing.
void	doParse(Parser parser, ParserContext context) Required by the ParserExtension interface and not meant to be called directly.
boolean	getAutoAddRows() Get the value of the autoAddRows property, which determines whether empty rows are automatically added to the bottom of the table when needed.
java.awt.Color	getBlankBackground() Returns the color that is used for blank areas in the table, below the rows of cells.
java.awt.Color	getCellBackground() Returns the color that is used as a background for cells in the table.
double	getCellContents(int row, int col) Get the number in the specified row and column.
int	getColumnCount() Get the number of columns in the table.
java.lang.String	getColumnName(int i) Get the name of column number i, where columns are numbered starting from zero.
protected Variable	getColumnVariable(int columnNum) Return a column variable for the specified column, where columns are numbered starting from 1.
int	getCurrentRowNumber() Return the current row number.
double	getEmptyCellValue() Get the value that is represented by an empty cell.
java.awt.Color	getGridColor() Returns the color that is used for the lines between cells in the table.
java.awt.Color	getLabelBackground() Returns the color that is used as a background for row numbers and column titles.
java.lang.String	getName() Get the name of the DataInputTable (which might be null).
int	getNonEmptyRowCount() Return the number of rows in the table, ignoring empty rows at the bottom of the table.
protected Variable	getRowNumberVariable() Get a variable that represents the current row number in the table, as set by the setCurrentRowNumber() method.
long	getSerialNumber() Get the serial number of the table.
boolean	getShowColumnTitles() Test whether the column name is shown at the top of each column.
boolean	getShowRowNumbers() Test whether row numbers are shown.
boolean	getThrowErrors() Get the value of the throwErrors property, which determines whether an error is thrown when an attempt is made to refer to the value of a cell that contains an invalid string.
void	insertRow() Insert a row before the row that contains the cell that the user is editing.
boolean	readFromStream(java.io.Reader in) Read data for table from the specified Reader.
void	setAutoAddRows(boolean auto) If the value of autoAddRows is true, then an empty row is added to the table automatically when the user attempts to move down from the last row of the table, provided that the last row is non-empty (so there can only be one auto-added row at a time).
void	setBlankBackground(java.awt.Color color) Get the color to be used as a background blank areas in the table, below the rows of cells.
void	setCellBackground(java.awt.Color color) Set the color to be used as a background for cells in the table.
void	setCellContents(int row, int col, double val) Put the given real number, val, in the cell in the specified row and column, where rows are numbered starting from 1 and columns are numbered starting from zero.
void	setColumnName(int i, java.lang.String name) Set the name of column number i, where columns are numbered starting from zero.
void	setCurrentRowNumber(int i) Set the current row in the table.
void	setEmptyCellValue(double val) Set the value that should be returned when the value of an empty cell is requested.
void	setGridColor(java.awt.Color color) Get the color to be used for the lines between cells in the table.
void	setLabelBackground(java.awt.Color color) Set the color to be used as a background for row numbers and column titles.
void	setName(java.lang.String name) Set the name of this DataTableInput.
void	setShowColumnTitles(boolean show) If set to true, then the column name is shown at the top of each column.
void	setShowRowNumbers(boolean show) If set to true, then the row number is shown at the left of each row.
void	setThrowErrors(boolean throwErr) Set the throwErrors property.

Methods inherited from class java.awt.Panel

addNotify, getAccessibleContext

Methods inherited from class java.awt.Container

add, add, add, add, add, addContainerListener, addImpl, countComponents, deliverEvent, doLayout, findComponentAt, findComponentAt, getAlignmentX, getAlignmentY, getComponent, getComponentAt, getComponentAt, getComponentCount, getComponents, getInsets, getLayout, getListeners, getMaximumSize, getMinimumSize, getPreferredSize, insets, invalidate, isAncestorOf, layout, list, list, locate, minimumSize, paint, paintComponents, paramString, preferredSize, print, printComponents, processContainerEvent, processEvent, remove, remove, removeAll, removeContainerListener, removeNotify, setFont, setLayout, update, validate, validateTree

Methods inherited from class java.awt.Component

action, add, addComponentListener, addFocusListener, addHierarchyBoundsListener, addHierarchyListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, addPropertyChangeListener, addPropertyChangeListener, bounds, checkImage, checkImage, coalesceEvents, contains, contains, createImage, createImage, disable, disableEvents, dispatchEvent, enable, enable, enableEvents, enableInputMethods, firePropertyChange, getBackground, getBounds, getBounds, getColorModel, getComponentOrientation, getCursor, getDropTarget, getFont, getFontMetrics, getForeground, getGraphics, getGraphicsConfiguration, getHeight, getInputContext, getInputMethodRequests, getLocale, getLocation, getLocation, getLocationOnScreen, getParent, getPeer, getSize, getSize, getToolkit, getTreeLock, getWidth, getX, getY, gotFocus, handleEvent, hasFocus, hide, imageUpdate, inside, isDisplayable, isDoubleBuffered, isEnabled, isFocusTraversable, isLightweight, isOpaque, isShowing, isValid, isVisible, keyDown, keyUp, list, list, list, location, lostFocus, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, postEvent, prepareImage, prepareImage, printAll, processComponentEvent, processFocusEvent, processHierarchyBoundsEvent, processHierarchyEvent, processInputMethodEvent, processKeyEvent, processMouseEvent, processMouseMotionEvent, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, repaint, requestFocus, reshape, resize, resize, setBackground, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setEnabled, setForeground, setLocale, setLocation, setLocation, setSize, setSize, setVisible, show, show, size, toString, transferFocus

Methods inherited from class java.lang.Object

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

Constructor Detail

DataTableInput

public DataTableInput()

Create a DataTableInput with no columns. Columns can be added later using the addColumn() methods. The table initially has no name.

DataTableInput

public DataTableInput(java.lang.String name,
                      java.lang.String[] columnNames)

Create a table with the specified column names. If columnNames is null, the number of columns is zero. The name can be null, if you don't need a name for the table. The length of the array determines the number of columns in the table.

DataTableInput

public DataTableInput(java.lang.String name,
                      int columns)

Create a table with the specified number of columns, named "A", "B", etc. The name can be null, if you don't need a name for the table. The number of columns can be zero.

Method Detail

doParse

public void doParse(Parser parser,
                    ParserContext context)

Required by the ParserExtension interface and not meant to be called directly. This is called by a parser if it encounters the name of the table in an expression. It parses the complete table reference, such as "data.A(3)" or "data.sum(A^2)".

Specified by:

doParse in interface ParserExtension

getNonEmptyRowCount

public int getNonEmptyRowCount()

Return the number of rows in the table, ignoring empty rows at the bottom of the table. Note that an empty row that precedes some non-empty row is included in the count.

getCellContents

public double getCellContents(int row,
                              int col)

Get the number in the specified row and column. Rows are numberd starting from 1, but columns are numbered starting from zero. If the specified cell does not exist in the table, Double.NaN is returned. If the cell is empty, emptyCellValue is returned. If the content of the cell does not define a legal real number, then the action depends on the value of the missingValueIsError property: If this property is true, then a JCMError is thrown; if it is false, then Double.NaN is returned.

setCellContents

public void setCellContents(int row,
                            int col,
                            double val)

Put the given real number, val, in the cell in the specified row and column, where rows are numbered starting from 1 and columns are numbered starting from zero. This is ignored if the specified row and column do not exist in the table.

setCurrentRowNumber

public void setCurrentRowNumber(int i)

Set the current row in the table. If the parameter is less than 1, the current row is set to 1. (The table keeps track of a "current row number", which is always greater than or equal to 1. This row number is used when a column variable or row number variable is evaluated. These variables can be added to a parser using the addVariablesToParser method, and can then be used in expressions parsed by that parser. When the row number variable, which is named rowNumber, is evaluated, its value is the current row number in the table. When a column variable is evaluated, its value is the number in the cell in the associated column and in the current row. The setCurrentRowNumber() method, in combination with the getNonEmptyRowCount() method allow you to iterate through the rows of the table and evaluate the expression for each row.)

getCurrentRowNumber

public int getCurrentRowNumber()

Return the current row number.

getColumnVariable

protected Variable getColumnVariable(int columnNum)

Return a column variable for the specified column, where columns are numbered starting from 1. The value of this variable is the number in the specified column and in the current row of the table (as set by the setCurrentRowNumber() method.) The name of the variable is the name of the column. This method is protected since variables are not meant to be used as regular variables. But they can be added to a Parser by calling the addVariablesToParser() method.)

getRowNumberVariable

protected Variable getRowNumberVariable()

Get a variable that represents the current row number in the table, as set by the setCurrentRowNumber() method. The name of the variable is rowNumber.

addVariablesToParser

public void addVariablesToParser(Parser p)

Add a row number variable (from the getRowNumberVariable() method) and a column variable for each column (from the getColumnVariable() method) to the parser. The parser will then be able to parse expressions that refer to these variables. The value of such an expression depends on the current row number, as set by setCurrentRowNumber().

getSerialNumber

public long getSerialNumber()

Get the serial number of the table. This is incremented each time the table changes in any way.

setThrowErrors

public void setThrowErrors(boolean throwErr)

Set the throwErrors property. If this is true, then a JCMError is thrown when an attempt is made to use the value of a cell that contains an invalid String. Note that referring to an empty cell is not an error. The default value is true.

getThrowErrors

public boolean getThrowErrors()

Get the value of the throwErrors property, which determines whether an error is thrown when an attempt is made to refer to the value of a cell that contains an invalid string.

setEmptyCellValue

public void setEmptyCellValue(double val)

Set the value that should be returned when the value of an empty cell is requested. The default value is Double.NaN. Another plausible value, in some circumstances, would be zero.

getEmptyCellValue

public double getEmptyCellValue()

Get the value that is represented by an empty cell.

setAutoAddRows

public void setAutoAddRows(boolean auto)

If the value of autoAddRows is true, then an empty row is added to the table automatically when the user attempts to move down from the last row of the table, provided that the last row is non-empty (so there can only be one auto-added row at a time). If the user leaves this row while it is still empty, it will automatically be deleted. The default value is true.

getAutoAddRows

public boolean getAutoAddRows()

Get the value of the autoAddRows property, which determines whether empty rows are automatically added to the bottom of the table when needed.

setName

public void setName(java.lang.String name)

Set the name of this DataTableInput. This is only needed if the table is to be added to a parser. The name should be a legal identifier.

Specified by:

setName in interface MathObject

Overrides:

setName in class java.awt.Component

getName

public java.lang.String getName()

Get the name of the DataInputTable (which might be null).

Specified by:

getName in interface MathObject

Overrides:

getName in class java.awt.Component

setColumnName

public void setColumnName(int i,
                          java.lang.String name)

Set the name of column number i, where columns are numbered starting from zero. If column variables are to be used or if the DataTableInput itself is to be added to a parser, then the name should be a legal identifier. If the showColumnTitles property is set to true, then column names are shown at the top of the table.

getColumnName

public java.lang.String getColumnName(int i)

Get the name of column number i, where columns are numbered starting from zero.

addRows

public void addRows(int rowCt)

Add the specified number of empty rows at the bottom of the table. If you want a table with a fixed number of rows, add them with this method and set the autoAddRows property to false.

insertRow

public void insertRow()

Insert a row before the row that contains the cell that the user is editing.

deleteCurrentRow

public void deleteCurrentRow()

Delete the row that contains the cell that the user is editing. However, if that is the only row in the table, just make the row empty.

clear

public void clear()

Remove all rows from the table, leaving just one empty row.

getColumnCount

public int getColumnCount()

Get the number of columns in the table.

addColumn

public int addColumn()

Add a column at the right side of the table, with all cells initially empty. The name of the columns will be single letter such as 'A', 'B', ...

addColumn

public int addColumn(java.lang.String name)

Add a column with the specified name at the right side of the table, with all cells initially empty. This is inefficient if the table already contains a bunch of non-empty rows.

getShowColumnTitles

public boolean getShowColumnTitles()

Test whether the column name is shown at the top of each column.

setShowColumnTitles

public void setShowColumnTitles(boolean show)

If set to true, then the column name is shown at the top of each column. The default value is false. This is meant to be called before the table has been shown on the screen, such as in the init() method of an applet. If you call it after the table has already been shown, you will have to validate the panel yourself.

getShowRowNumbers

public boolean getShowRowNumbers()

Test whether row numbers are shown.

setShowRowNumbers

public void setShowRowNumbers(boolean show)

If set to true, then the row number is shown at the left of each row. The default value is false. This is meant to be called before the table has been shown on the screen, such as in the init() method of an applet. If you call it after the table has already been shown, you will have to validate the panel yourself.

getLabelBackground

public java.awt.Color getLabelBackground()

Returns the color that is used as a background for row numbers and column titles.

setLabelBackground

public void setLabelBackground(java.awt.Color color)

Set the color to be used as a background for row numbers and column titles. The default is a very light gray.

getCellBackground

public java.awt.Color getCellBackground()

Returns the color that is used as a background for cells in the table.

setCellBackground

public void setCellBackground(java.awt.Color color)

Set the color to be used as a background for cells in the table. The default is a light yellow.

getBlankBackground

public java.awt.Color getBlankBackground()

Returns the color that is used for blank areas in the table, below the rows of cells.

setBlankBackground

public void setBlankBackground(java.awt.Color color)

Get the color to be used as a background blank areas in the table, below the rows of cells. The default is a gray.

getGridColor

public java.awt.Color getGridColor()

Returns the color that is used for the lines between cells in the table.

setGridColor

public void setGridColor(java.awt.Color color)

Get the color to be used for the lines between cells in the table. The default is a blue.

readFromStream

public boolean readFromStream(java.io.Reader in)

Read data for table from the specified Reader. One row is filled from each non-empty line of input. The line should contain numbers separated by spaces/tabs/commas. The word "undefined" can be used to represent an empty cell. Otherwise, if a non-number is encountered, an error occurs. If not enough numbers are found on a line, the extra columns are filled with empties. After filling all columns, extra data on the line is ignored. Data currently in the table is removed and replaced (if no error occurs during reading). In the case of an error, if throwErrors is true, then a JCMError is thrown; if throwErrors is false, no error is thrown, but the return value is false. If no error occurs, the return value is true. If an error occurs, the previous data in the table is left unchanged.