General (ChargerLib)

Object
- chargerlib.General

```
public class General
extends Object
```
Some generally useful utilities

Field Summary

Fields
Modifier and Type	Field and Description
`static int`	`AcceleratorKey` Key to use with shortcut commands; i.e., CNTL on PC, Cmd on Mac
`static Border`	`BeveledBorder`
`static Color`	`chargerBlueColor`
`static int`	`defaultMaxUndoLevels`
`static BasicStroke`	`defaultStroke`
`static boolean`	`infoOn`
`private static Border`	`loweredBevel`
`private static Border`	`raisedBevel`

Constructor Summary

Constructors
Constructor and Description

General()

Constructors
Constructor and Description
`General()`

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method and Description
`static String`	`a_or_an(String s)` Prints a string with a prefix, deciding whether to use "a" or "an" for the article, based on the string.
`static void`	`addChangeListener(JTextComponent textComponent, ChangeListener changeListener)` Installs a listener to receive notification when the text of any `JTextComponent` is changed.
`static void`	`adjustTableColumnWidths(JTable table)` For each column of a JTable, scans every entry and determines the maximum width for the column.
`static File`	`chooseInputFile(String query, String filename, File sourceDirectoryFile, FileFilter filter)` Handles the choosing of an input file.
`static File`	`chooseOutputFile(String query, String filename)` Handles the choosing of an input file by the user, with possible user intervention.
`static void`	`consoleMsg(String s)` Displays a status message on System.out
`static String`	`displayAsHex(byte[] bytes)`
`static void`	`drawCenteredString(Graphics2D g, String s, double x, double y)` Displays a centered text string in black
`static void`	`drawCenteredString(Graphics2D g, String s, double x, double y, Color c)` Displays the text string centered about the point x,y in the given color.
`static void`	`drawCenteredString(Graphics2D g, String s, Point2D.Double p, Color c)`
`static long`	`elapsedTime(long time)` Returns a printable string to show the time elapsed since a given time.
`static boolean`	`equalsToRoundedInt(Rectangle2D.Double r1, Rectangle2D.Double r2)` If the rectangles' location and dimension all round (Math.round) to the same int (pixel) then return true.
`static void`	`error(String s)` Displays an error message on System.out
`static String`	`excludeChars(String s, String set)` Convert any forbidden characters to a space character.
`static Point2D.Double`	`get_line_intersection(Line2D.Double pLine1, Line2D.Double pLine2)` Figure out the point where the two lines intersect.
`static Point2D.Double`	`get_rectangle_line_intersection(Rectangle2D.Double rect, Line2D.Double line)`
`static Point`	`get2ndScreenOrigin()` Determine whether there's another screen, and if so, get the x,y of its bounds.
`static String`	`getFileExtension(String filename)` Identifies the extension part of a filename string.
`static String`	`getFileFromClassPath(String desiredFoldername, String desiredFilename)` Returns the contents of a file after first deciding whether to load from a jar file or from a directory and class hierarchy.
`static ImageIcon`	`getIconFromClassPath(String gifname)` Returns the icon image after first deciding whether to load from a jar file or from a directory and class hierarchy.
`static String`	`getPathname(String s)` Extracts the prepended pathname part of a supposed file name string
`static Rectangle`	`getScreenBounds(boolean useMainScreen)` Find the bounds of one of the available screens.
`static String`	`getSimpleFilename(String s)` Extracts the suffixed filename part of a supposed file name string, incl extensions.
`static String`	`getXmlText(org.w3c.dom.Element element, String tagname)` Find the value of the text bracketed inside the given tagname.
`static boolean`	`hasPathName(String s)` Tells whether there's a path prepended or not
`static void`	`hideTableColumn(TableColumn col)`
`static void`	`info(String s)` Displays a status message on System.out
`static Point2D.Double`	`make2DDouble(Point2D.Double point)` Creates a clone of the point.
`static Point2D.Double`	`make2DDouble(Point2D.Float p)`
`static Rectangle2D.Double`	`make2DDouble(Rectangle2D.Double rect)` Creates a clone of the rectangle.
`static String`	`makeLegalChars(String s, String characterSet)` Makes sure that no "illegal" characters remain in the string.
`static Point2D.Double`	`midPoint(Point2D.Double p1, Point2D.Double p2)`
`static String`	`ordinal(int num)` Converts a number to its ordinal description.
`static File`	`queryForInputFile(String query, File sourceDirectoryFile, FileFilter filter)` Queries the user to find a file to be used for input.
`static File`	`queryForOutputFile(String query, File initialDirectory, String filename)` Queries the user to find a file to be used for input.
`static String`	`removeSubstring(String s, int startPos, int endPos)`
`static ArrayList`	`repeatingVector(int theSize, Object value)` Creates a vector of a given size where every element has the same value.
`static void`	`setTableColumnWidth(TableColumn col, int width)`
`static void`	`showArrayList(ArrayList v)`
`static String`	`splitWithSeparator(String original, String regex, String sep)` Splits a string according to each occurrence of a regular expression, inserting a separator between each part of the string.
`static String`	`stripFileExtension(String filename)` Extracts the extension part of a filename string.
`static void`	`tearDownMenu(JMenu menu)` Does a complete erasure of a JMenu.
`static String`	`toXML(org.w3c.dom.Node doc)` Pretty print the doc as given.
`static void`	`warning(String s)` Displays a warning message on System.out
`static void`	`writeToFile(File f, String s, boolean append)` A generic file writer, usable by any Charger class

Methods inherited from class Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - chargerBlueColor
```
public static Color chargerBlueColor
```
  - raisedBevel
```
private static Border raisedBevel
```
  - loweredBevel
```
private static Border loweredBevel
```
  - BeveledBorder
```
public static Border BeveledBorder
```
  - infoOn
```
public static boolean infoOn
```
  - defaultMaxUndoLevels
```
public static int defaultMaxUndoLevels
```
  - AcceleratorKey
```
public static int AcceleratorKey
```
    Key to use with shortcut commands; i.e., CNTL on PC, Cmd on Mac
  - defaultStroke
```
public static BasicStroke defaultStroke
```
- Constructor Detail
  - General
```
public General()
```
- Method Detail
  - info
```
public static void info(String s)
```
    Displays a status message on System.out
    
    Parameters:
    
    s - the status message to be shown
    
    See Also:
    
    Global#infoOn, Global#ShowBoringDebugInfo
  - warning
```
public static void warning(String s)
```
    Displays a warning message on System.out
    
    Parameters:
    
    s - the warning message to be shown
  - error
```
public static void error(String s)
```
    Displays an error message on System.out
    
    Parameters:
    
    s - the error message to be shown
  - consoleMsg
```
public static void consoleMsg(String s)
```
    Displays a status message on System.out
    
    Parameters:
    
    s - the status message to be shown
  - drawCenteredString
```
public static void drawCenteredString(Graphics2D g,
                                      String s,
                                      double x,
                                      double y,
                                      Color c)
```
    Displays the text string centered about the point x,y in the given color. taken from p 586, Naughton and Schildt, 1996
    
    Parameters:
    
    g - the current Graphics context
    
    s - the string to be displayed
    
    x - horizontal position of the centerpoint (in pixels)
    
    y - vertical position of the centerpoint (in pixels)
    
    c - the color to be displayed
  - drawCenteredString
```
public static void drawCenteredString(Graphics2D g,
                                      String s,
                                      double x,
                                      double y)
```
    Displays a centered text string in black
    
    See Also:
    
    CGUtil#drawCenteredString
  - drawCenteredString
```
public static void drawCenteredString(Graphics2D g,
                                      String s,
                                      Point2D.Double p,
                                      Color c)
```
  - queryForInputFile
```
public static File queryForInputFile(String query,
                                     File sourceDirectoryFile,
                                     FileFilter filter)
```
    Queries the user to find a file to be used for input.
    
    Parameters:
    
    sourceDirectoryFile - starting point directory (user may change)
    
    filter - allows the viewing of only certain files.
    
    Returns:
    
    an existing file, possibly unreadable; null if user cancels.
  - setTableColumnWidth
```
public static void setTableColumnWidth(TableColumn col,
                                       int width)
```
  - queryForOutputFile
```
public static File queryForOutputFile(String query,
                                      File initialDirectory,
                                      String filename)
```
    Queries the user to find a file to be used for input.
    
    Parameters:
    
    query - the title for the querying dialog
    
    initialDirectory - path for the directory where we'll start trying to query
    
    filename - initial choice of where to point the saving operation (user may change)
    
    Returns:
    
    an existing file, possibly unreadable; null if user cancels.
  - getFileExtension
```
public static String getFileExtension(String filename)
```
    Identifies the extension part of a filename string.
    
    Parameters:
    
    filename - any string
    
    Returns:
    
    suffix extension (not including'.'); null if no suffix
  - getFileFromClassPath
```
public static String getFileFromClassPath(String desiredFoldername,
                                          String desiredFilename)
```
    Returns the contents of a file after first deciding whether to load from a jar file or from a directory and class hierarchy. If Charger is run by invoking its .jar file (the usual way), then this function assumes the JAR file was created on a Mac or Linux system with Mac or Linux path element separators. That is, on a Windows platform, it's still looking for folder/filename even though its real file name ought to be folder\filename.
    
    Parameters:
    
    desiredFilename - file name of the text file, relative to the classpath
    
    desiredFoldername - folder name containing the text file
    
    Returns:
    
    contents of the file as a string
  - repeatingVector
```
public static ArrayList repeatingVector(int theSize,
                                        Object value)
```
    Creates a vector of a given size where every element has the same value.
    
    Parameters:
    
    theSize - The desired vector size
    
    value - The value of each element
    
    Returns:
    
    a vector with the appropriate values.
  - chooseInputFile
```
public static File chooseInputFile(String query,
                                   String filename,
                                   File sourceDirectoryFile,
                                   FileFilter filter)
```
    Handles the choosing of an input file.
    
    Parameters:
    
    filename - the initial selection of a file; null if none is known
    
    sourceDirectoryFile - initial directory (user may change)
    
    filter - allows the viewing of only certain files.
    
    Returns:
    
    an absolute File, possibly permission-protected.
  - get2ndScreenOrigin
```
public static Point get2ndScreenOrigin()
```
    Determine whether there's another screen, and if so, get the x,y of its bounds. If there are more than two screens, will return an origin for any one other than the main screen.
    
    Returns:
    
    0,0 if there isn't a second screen.
  - chooseOutputFile
```
public static File chooseOutputFile(String query,
                                    String filename)
```
    Handles the choosing of an input file by the user, with possible user intervention.
    
    Parameters:
    
    query - the prompt string for the user
    
    filename - the initial selection of a file; null if none is known. If it's an absolute path name, then the directory is obtained from it, otherwise some implementation-dependent directory is chosen.
    
    Returns:
    
    an absolute File, possibly permission-protected.
  - getScreenBounds
```
public static Rectangle getScreenBounds(boolean useMainScreen)
```
    Find the bounds of one of the available screens.
    
    Parameters:
    
    useMainScreen - whether to get the bounds of the main screen or not
    
    Returns:
    
    if true, return the main screen (x=0,y=0) bounds, if false, then the first non-main screen.
  - elapsedTime
```
public static long elapsedTime(long time)
```
    Returns a printable string to show the time elapsed since a given time.
    
    Parameters:
    
    time - Start time
    
    Returns:
    
    number of millisecons since the start time
  - getIconFromClassPath
```
public static ImageIcon getIconFromClassPath(String gifname)
```
    Returns the icon image after first deciding whether to load from a jar file or from a directory and class hierarchy. If a jar file, then see if there's a directory named for Hub.gifpath. If Charger is run by invoking its .jar file (the usual way), then this function assumes the JAR file was created on a Mac or Linux system with Mac or Linux path element separators. That is, on a Windows platform, it's still looking for GIF/filename even though its real file name ought to be GIF\filename.
    
    Parameters:
    
    gifname - file name of the icon's image, relative to the classpath
  - getSimpleFilename
```
public static String getSimpleFilename(String s)
```
    Extracts the suffixed filename part of a supposed file name string, incl extensions.
    
    Parameters:
    
    s - supposed file name string
    
    Returns:
    
    filename part of the string; if no path, then returns s
  - hideTableColumn
```
public static void hideTableColumn(TableColumn col)
```
  - toXML
```
public static String toXML(org.w3c.dom.Node doc)
```
    Pretty print the doc as given.
    
    Parameters:
    
    doc - Any DOM document
    
    Returns:
    
    a pretty-printed string, omitting an XML header
  - showArrayList
```
public static void showArrayList(ArrayList v)
```
  - ordinal
```
public static String ordinal(int num)
```
    Converts a number to its ordinal description. For example, the value 1 become "1st" etc.
  - displayAsHex
```
public static String displayAsHex(byte[] bytes)
```
  - removeSubstring
```
public static String removeSubstring(String s,
                                     int startPos,
                                     int endPos)
```
    Parameters:
    
    s -
    
    startPos - the index (starting at 0) of the start of the string to remove
    
    endPos - the index (starting at 0) of the start of the string to remove
    
    Returns:
    
    The resulting string after removal
  - get_line_intersection
```
public static Point2D.Double get_line_intersection(Line2D.Double pLine1,
                                                   Line2D.Double pLine2)
```
    Figure out the point where the two lines intersect.
    
    Parameters:
    
    pLine1 -
    
    pLine2 -
    
    Returns:
    
    null, if the lines do not intersect.
  - adjustTableColumnWidths
```
public static void adjustTableColumnWidths(JTable table)
```
    For each column of a JTable, scans every entry and determines the maximum width for the column. Also checks the header row labels.
    
    Parameters:
    
    table - the table to be adjusted.
  - a_or_an
```
public static String a_or_an(String s)
```
    Prints a string with a prefix, deciding whether to use "a" or "an" for the article, based on the string. For example a_or_an( "element" ) returns "an element", whereas a_or_an( "person" ) returns "a person"
  - midPoint
```
public static Point2D.Double midPoint(Point2D.Double p1,
                                      Point2D.Double p2)
```
  - equalsToRoundedInt
```
public static boolean equalsToRoundedInt(Rectangle2D.Double r1,
                                         Rectangle2D.Double r2)
```
    If the rectangles' location and dimension all round (Math.round) to the same int (pixel) then return true. Otherwise false.
    
    Parameters:
    
    r1 -
    
    r2 -
    
    Returns:
  - writeToFile
```
public static void writeToFile(File f,
                               String s,
                               boolean append)
```
    A generic file writer, usable by any Charger class
  - getPathname
```
public static String getPathname(String s)
```
    Extracts the prepended pathname part of a supposed file name string
    
    Parameters:
    
    s - supposed file name string
    
    Returns:
    
    pathname part of the string (including the trailing file separator); if no path, then returns "" (not null!)
  - hasPathName
```
public static boolean hasPathName(String s)
```
    Tells whether there's a path prepended or not
    
    Parameters:
    
    s - supposed file name string
    
    Returns:
    
    true if there seems to be a pathname, false otherwise
  - tearDownMenu
```
public static void tearDownMenu(JMenu menu)
```
    Does a complete erasure of a JMenu. For each item in the menu, gets rid of all listeners and removes item from menu.
    
    Parameters:
    
    menu -
  - excludeChars
```
public static String excludeChars(String s,
                                  String set)
```
    Convert any forbidden characters to a space character.
    
    Parameters:
    
    s -
    
    set - The set of excluded characters, each of which will be converted to a space.
    
    Returns:
  - makeLegalChars
```
public static String makeLegalChars(String s,
                                    String characterSet)
```
    Makes sure that no "illegal" characters remain in the string. Strips out any illegal characters silently.
    
    Parameters:
    
    the - string to be examined
    
    the - character set allowed for that string.
    
    See Also:
    
    CharacterSets
  - splitWithSeparator
```
public static String splitWithSeparator(String original,
                                        String regex,
                                        String sep)
```
    Splits a string according to each occurrence of a regular expression, inserting a separator between each part of the string.
    
    Parameters:
    
    original - The original string to be split
    
    regex - A regular expression to be found in the string. Follows the same rules as String#split
    
    sep - The string to be inserted between the parts (if null, then this method has no effect)
    
    Returns:
    
    a new string with the appropriate separators inserted if the regex was found
  - make2DDouble
```
public static Rectangle2D.Double make2DDouble(Rectangle2D.Double rect)
```
    Creates a clone of the rectangle.
    
    Parameters:
    
    rect -
    
    Returns:
    
    a new instance
  - make2DDouble
```
public static Point2D.Double make2DDouble(Point2D.Double point)
```
    Creates a clone of the point.
    
    Parameters:
    
    point -
    
    Returns:
    
    a new instance
  - make2DDouble
```
public static Point2D.Double make2DDouble(Point2D.Float p)
```
  - stripFileExtension
```
public static String stripFileExtension(String filename)
```
    Extracts the extension part of a filename string.
    
    Parameters:
    
    filename - any string
    
    Returns:
    
    suffix extension (not including'.'); null if no suffix
  - getXmlText
```
public static String getXmlText(org.w3c.dom.Element element,
                                String tagname)
```
    Find the value of the text bracketed inside the given tagname. Returns null if it is not found.
    
    Parameters:
    
    element -
    
    tagname -
    
    Returns:
    
    string value of the text inside the tag (using getTextContent); null if not found.
  - get_rectangle_line_intersection
```
public static Point2D.Double get_rectangle_line_intersection(Rectangle2D.Double rect,
                                                             Line2D.Double line)
```
  - addChangeListener
```
public static void addChangeListener(JTextComponent textComponent,
                                     ChangeListener changeListener)
```
    Installs a listener to receive notification when the text of any JTextComponent is changed. Internally, it installs a DocumentListener on the text component's Document, and a PropertyChangeListener on the text component to detect if the Document itself is replaced.
    
    Parameters:
    
    textComponent - any text component, such as a JTextField or JTextArea
    
    changeListener - a listener to receieve ChangeEvents when the text is changed; the source object for the events will be the text component
    
    Throws:
    
    NullPointerException - if either parameter is null obtained from https://stackoverflow.com/questions/3953208/value-change-listener-to-jtextfield

Class General

Field Summary

Constructor Summary

Method Summary

Methods inherited from class Object

Field Detail

chargerBlueColor

raisedBevel

loweredBevel

BeveledBorder

infoOn

defaultMaxUndoLevels

AcceleratorKey

defaultStroke

Constructor Detail

General

Method Detail

info

warning

error

consoleMsg

drawCenteredString

drawCenteredString

drawCenteredString

queryForInputFile

setTableColumnWidth

queryForOutputFile

getFileExtension

getFileFromClassPath

repeatingVector

chooseInputFile

get2ndScreenOrigin

chooseOutputFile

getScreenBounds

elapsedTime

getIconFromClassPath

getSimpleFilename

hideTableColumn

toXML

showArrayList

ordinal

displayAsHex

removeSubstring

get_line_intersection

adjustTableColumnWidths

a_or_an

midPoint

equalsToRoundedInt

writeToFile

getPathname

hasPathName

tearDownMenu

excludeChars

makeLegalChars

splitWithSeparator

make2DDouble

make2DDouble

make2DDouble

stripFileExtension

getXmlText

get_rectangle_line_intersection

addChangeListener