(As reported by my colleague Michael Diamond)

When jshell prints out a stacktrace, it needs to take missing filenames into account, else it will get NullPointerException in jdk.jshell.Eval.translateExceptionStack, causing jshell itself to terminate.

# Recipe:
$ (cat fail/Fail.java; javac -d . -g:none fail/Fail.java; jshell --class-path .)
package fail;
public class Fail {
  static { int x = 1 / 0; }
}
|  Welcome to JShell -- Version 14-ea
|  For an introduction type: /help intro

jshell> Class.forName("fail.Fail");
Exception in thread "main" java.lang.NullPointerException
        at jdk.jshell/jdk.jshell.Eval.translateExceptionStack(Eval.java:1109)
        at jdk.jshell/jdk.jshell.Eval.asEvalException(Eval.java:907)
        at jdk.jshell/jdk.jshell.Eval.asJShellException(Eval.java:924)
        at jdk.jshell/jdk.jshell.Eval.asEvalException(Eval.java:908)
        at jdk.jshell/jdk.jshell.Eval.declare(Eval.java:888)
        at jdk.jshell/jdk.jshell.Eval.eval(Eval.java:140)
        at jdk.jshell/jdk.jshell.JShell.eval(JShell.java:493)
        at jdk.jshell/jdk.internal.jshell.tool.JShellTool.processSource(JShellTool.java:3558)
        at jdk.jshell/jdk.internal.jshell.tool.JShellTool.processSourceCatchingReset(JShellTool.java:1305)
        at jdk.jshell/jdk.internal.jshell.tool.JShellTool.processInput(JShellTool.java:1203)
        at jdk.jshell/jdk.internal.jshell.tool.JShellTool.run(JShellTool.java:1176)
        at jdk.jshell/jdk.internal.jshell.tool.JShellTool.start(JShellTool.java:975)
        at jdk.jshell/jdk.internal.jshell.tool.JShellToolBuilder.start(JShellToolBuilder.java:254)
        at jdk.jshell/jdk.internal.jshell.tool.JShellToolProvider.main(JShellToolProvider.java:120)

(jshell died ...)