drawString should have better runtime error handling so that a bogus
argument to drawString doesn't cause the applet to hang.

overpaint.java is:



import java.lang.*;
import java.awt.*;
import java.applet.*;

/**
 * Try to crash AWT by asking it to draw a huge string
 *
 * AWT should throw an exception, probably, but instead
 * it goes on a trip through Xerror BadRequest and
 * eventually hangs the applet
 */

public class overpaint extends Applet {
    int count = 0;
    String s = "supercalifragilisticexpealidocious";
    String t;

    public void init() {
setLayout(new BorderLayout());
add("North", new Button("Exit"));
    }

    public void start() {
// Send in a string that is a tad too big, to g.drawString
oversizedString(s);
overpaint(t);
   }

    public void oversizedString(String s){
int i = 0;

// Construct a string that is jjjuuusstttt too big
t = s;
try {
// Quickly build up a big string
for(i=0; i<16; i++) {
t = t.concat(t);
}
// Then push it over the edge
for(i=0; i<17; i++) {
t = t.concat("Z");
count++;
}
} catch (OutOfMemoryError e) {
System.out.println("Sorry, Charlie, out of memory when t is length " + t.length());
}
   }

    public void overpaint(String s){
System.out.println("Before drawString, in overpaint");
getGraphics().drawString(s,10,10);
System.out.println("After drawString, in overpaint");
    }

    public boolean action(Event e, Object arg) {
String label = (String)arg;
if (label.equals("Exit")){
System.exit(10);
}
return true;
    }
}



overpaint.html is:

<title>overpaint</title>
<hr>
<applet code="overpaint.class" width=137 height=42>
</applet>
<hr>
<a href="overpaint.java">The source, Luke.</a>



and output I get is:
puffin% puffin% !!
appletviewer overpaint.html
status: applet loaded
status: applet initialized
Before drawString, in overpaint
After drawString, in overpaint
Xerror BadLength (poly request too large or internal Xlib length error)
Major opcode 75 (X_PolyText16)
Xerror BadRequest (invalid request code or no such operation)
Major opcode 0 (Unknown)
Xerror BadRequest (invalid request code or no such operation)
Major opcode 0 (Unknown)

(etc, for approx 3,200 such Xerrors)