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Netscape wont show my applet

843807Aug 21 2001 — edited Aug 21 2001
Can anyone help? I cannot run the applet I have written in netscape. The applet reads data from a text file, parses it and prints out results on a graph. It works fine in Internet Explorer 5.5 but refuses to show in Nescape Navigator 4.7 when I see the following exception in the Java console. I include the code for the init() method below and fot the other method mentioned in the exception, parseTextDataBase() in case you need to read it(Important bits in bold. If anyone has any ideas otr a solution I'd be grateful. Thanks, .....John Loughran, Ireland

Applet::init() // a SOP that tells me init() was reached

netscape.security.AppletSecurityException: security.class from local disk trying to access url: file:/C|/Documents and Settings/jloughran/My Documents/webApplet/SimRecDataBase960.txt
at java.lang.Throwable.<init>(Compiled Code)
at java.lang.Exception.<init>(Compiled Code)
at java.lang.RuntimeException.<init>(Compiled Code)
at java.lang.SecurityException.<init>(Compiled Code)
at netscape.security.AppletSecurityException.<init>
(Compiled Code)
at netscape.security.AppletSecurityException.<init>(Compiled Code)
at netscape.security.AppletSecurity.checkURLConnect(Compiled Code)
at java.lang.SecurityManager.checkURLConnect(Compiled Code)
at netscape.net.URLConnection.connect(Compiled Code)
at netscape.net.URLConnection.getInputStream(Compiled Code)
at java.net.URL.openStream(Compiled Code)
at SimRec.parseTextDataBase(Compiled Code)
at WebApplet.init(Compiled Code)
at Netscape.applet.DerivedAppletFrame$InitAppletEvent
.dispatch(Compiled Code)
at java.awt.EventDispatchThread$EventPump
.dispatchEvents(Compiled Code)
at java.awt.EventDispatchThread.run(Compiled Code)
at netscape.applet.DerivedAppletFrame$AppletEvent
DispatchThread.run(Compiled Code)

public void init()
{
mayPrintln("Applet::init()"); // calls System.out.println

// Background and fonts code not shown
try {
aEPAppletURL = new URL(getCodeBase(), "SimRecDataBase960.txt");
//} catch (MalformedURLException mue) {
} catch (Exception mue) {
mayPrintln("Bad URL");
}

/* parse the text file into a vector of recordV's */
allSimRecsV = aSimRec.parseTextDataBase();
/** Configure componenents in topLPaneland then other ones */
configureTopLeftComponents();

/* note and count choice items from the recordsV for choice 1 */
choiceItemsVA[1] = SimRec.noteChoiceItems(choiceNo[1], choiceNoS[0], allSimRecsV);
// add choice1Items to the display
for (int i = 0; i < choiceItemsVA[1].size(); i++)
{
serverPlatformOSChoice.addItem(choiceItemsVA[1].elementAt(i).toString());
}

//mayPrintln("After configureTopLeftComponents: choice = "+ serverPlatformOSChoice.getSelectedIndex());
configureButtons();// contains controls for starting, stopping and clearing graph configureOtherComponents();
placeComponents();

/** Start the graph */
currentGraph.startGraphLayout();
currentGraph.startThread(); // starts the graph thread1 running

} // ends init()

In case you are still awake I include the code for aSimRec.parseTextDataBase()

public Vector parseTextDataBase()
{
// locate the file at an absolute URL, then read it in
try {
aEPAppletURL = WebApplet.aEPAppletURL;
SimRecDBBufReader = new BufferedReader
(new InputStreamReader(aEPAppletURL.openStream()));
}
catch (FileNotFoundException fnfe) { // if file not found
WebApplet.mayPrintln("FileNotFound");
}
catch (IOException e) { // if error in reading URL
WebApplet.mayPrintln("Error reading simulation records TextDataBase or URL");
}

// start parsing text database file
boolean eof = false;
try
{ // read first line
dBLine = SimRecDBBufReader.readLine(); // goes to first line of file
if (dBLine == null)
eof = true;

while (eof == false)
{
tempRecordV = null; // leave it empty for next iteration
Vector tempRecordV = new Vector();
dBLine = dBLine.trim(); /** Removes white space from both ends of this string */
dBLineLength = dBLine.length ();

if(dBLine.startsWith (comment)); // do 0
else if(dBLine.equals("")); // do 0
else
{
// note the first and last character index of each field, store the substring as a field
beginIndex = 0; // index of char at start of each "field"
while (beginIndex < dBLineLength)
{
endIndex = beginIndex; // both 0 initially
while (dBLine.charAt(endIndex) != delimiter
&& endIndex < dBLineLength - 1)
{
endIndex++;
//i++;
}
fieldString = dBLine.substring(beginIndex, endIndex);
tempRecordV.addElement(fieldString); // adds the field string to the record vector

// jumps while loop forward in chunks to maintain linear complexity
beginIndex = endIndex + 1; // brings bI to just after the next delimiter
} // end while bI < line length
simRecordsV.addElement(tempRecordV);
} // end else

dBLine = SimRecDBBufReader.readLine(); // goes to next line of file
if (dBLine == null)
eof = true;
} // end while not eof
} //end try
catch (EOFException eofe) { // if file ends
eof = true;
WebApplet.mayPrintln("End of file reached unexpectedly");
} catch (IOException iof) {
eof = true;
WebApplet.mayPrintln("I/O exception");
}
WebApplet.mayPrintln("all sim recs read in");
return simRecordsV;
} // end parseTextDataBase()

Thanks for any help in advance. :-)
John
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Locked on Sep 18 2001
Added on Aug 21 2001
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