Class WebSim

java.lang.Object
   |
   +----java.awt.Component
           |
           +----java.awt.Container
                   |
                   +----java.awt.Panel
                           |
                           +----java.applet.Applet
                                   |
                                   +----WebSim

public class WebSim

extends Applet

implements Parsable

This code is (c) 1996-1998 Leemon Baird <leemon@cs.cmu.edu>, http://www.cs.cmu.edu/~baird
The source and object code may be redistributed freely. If the code is modified, please state so in the comments.

Version:

1.05, 11 May 97

Author:

Leemon Baird

myThreadGroup

The thread group containing this thread (and all other WebSim threads)

restartNumber

All projects check this occasionally, and restart when it changes

watchManager

This static variable allows any thread in memory (such as another Applet like VRMLInterface) to communicate with WebSim's WatchManager.

watchManagerGuard

Synchronize on watchManagerGuard before attempting to read or write watchManager.

WebSim()

constructor for WebSim includes setting the background color and layout manager

WebSim(String, int, int, int, int)

Instantiate a WebSim manually rather than with a browser or applet viewer.

BNF(int)

destroy()

The browser calls this when quitting.

destroyAll()

close all windows, kill all threads, dispose of all Graphics contexts

getAppletInfo()

Information about the applet that a browser or Java interpretor can give the user

getParameterInfo()

Parameter info that a browser or Java interpretor can give the user

getParameters(int)

Return a parameter array if BNF(), parse(), and unparse() are to be automated, null otherwise.

initialize(int)

Initialize, either partially or completely.

parse(Parser, int)

parseAndRun()

parses the BNF string and runs a set of projects.

resumeAllThreads()

resume all threads created by WebSim that have been suspended

saveFile()

save everything as a WebSim HTML file.

setWatchManager(WatchManager, String)

Register all variables with this WatchManager.

start()

Parse projects and start them running in separate threads

stop()

The browser calls this when the document is no longer on the screen, either because another Web page has been loaded, or because the current window was minimized.

stopAllThreads()

stop all threads created by WebSim

suspendAllThreads()

suspend all threads created by WebSim

unparse(Unparser, int)

unparseAll()

Unparse everything into a file, asking the user for the filename and whether to overwrite it if it exists.

unparseAll(String, boolean)

Unparse everything into the given file, and if it is overwriting an existing file, and makeBackup, then rename the old file *.BAK, and delete any existing .BAK with that same name

 public static WatchManager watchManager

This static variable allows any thread in memory (such as another Applet like VRMLInterface) to communicate with WebSim's WatchManager. If there are several WatchManagers, then it gives the one belonging to the last WebSim Project that finished initializing. To wait for the WatchManager to become available then put it into a new local variable called watchManager, run the following code:

            WatchManager watchManager;
            synchronized(WebSim.watchManagerGuard) {
                if (WebSim.watchManager==null)
                        try {
                            WebSim.watchManagerGuard.wait();
                        } catch(InterruptedException e) {
                        }
                watchManager=WebSim.watchManager;
            }
                                                                          

 public static Double watchManagerGuard

Synchronize on watchManagerGuard before attempting to read or write watchManager. Why is there a separate variable just for the guard? This is a workaround for a BUG: it's needed in Netscape 3.0 for SunOs 4, but not in Netscape for Win95/NT.

 public static int restartNumber

All projects check this occasionally, and restart when it changes

 public ThreadGroup myThreadGroup

The thread group containing this thread (and all other WebSim threads)

 public WebSim()

constructor for WebSim includes setting the background color and layout manager

 public WebSim(String bnfString,
               int x,
               int y,
               int width,
               int height)

Instantiate a WebSim manually rather than with a browser or applet viewer. The BNF code is in bnfString, and the window has upper-left corner (x,y) and dimensions (width,height).

 public Object[][] getParameters(int lang)

Return a parameter array if BNF(), parse(), and unparse() are to be automated, null otherwise.

See Also:

getParameters

 public String getAppletInfo()

Information about the applet that a browser or Java interpretor can give the user

Overrides:

getAppletInfo in class Applet

 public String[][] getParameterInfo()

Parameter info that a browser or Java interpretor can give the user

Overrides:

getParameterInfo in class Applet

 public void start()

Parse projects and start them running in separate threads

Overrides:

start in class Applet

 public void parseAndRun()

parses the BNF string and runs a set of projects.

 public void stop()

The browser calls this when the document is no longer on the screen, either because another Web page has been loaded, or because the current window was minimized. It should kill all threads and release all graphics contexts.

Overrides:

stop in class Applet

 public void destroyAll()

close all windows, kill all threads, dispose of all Graphics contexts

 public void destroy()

The browser calls this when quitting. It should kill all threads and release all graphics contexts.

Overrides:

destroy in class Applet

 public void stopAllThreads()

stop all threads created by WebSim

 public void suspendAllThreads()

suspend all threads created by WebSim

 public void resumeAllThreads()

resume all threads created by WebSim that have been suspended

 public void unparseAll()

Unparse everything into a file, asking the user for the filename and whether to overwrite it if it exists.

 public void unparseAll(String filename,
                        boolean makeBackup)

Unparse everything into the given file, and if it is overwriting an existing file, and makeBackup, then rename the old file *.BAK, and delete any existing .BAK with that same name

 public void saveFile()

save everything as a WebSim HTML file.

 public void initialize(int level)

Initialize, either partially or completely.

See Also:

initialize

 public void setWatchManager(WatchManager wm,
                             String name)

Register all variables with this WatchManager. This method should register all the variables in this object and in those it links to. The name of each variable should be appended to the end of the String name.

 public String BNF(int lang)

 public void unparse(Unparser u,
                     int lang)

 public Object parse(Parser p,
                     int lang) throws ParserException