No need to explicitly use javaw on Windows

[urmuzov]

My app has different subcommands, one of which launches Lanterna UI. This required me to have a launcher .bat file on windows, that selects java or javaw depending on the command.

Recenly I noticed that debugger in IntelliJ IDEA uses java.exe, but launches SwingTerminalWindow correctly.

After debugging, the difference I found is in behaviour of DefaultTerminalFactory.hasTerminal:

• On Windows form cmd: true
• On Linux (WSL in my case): true
• In IntelliJ debugger: false

So in this function (see comments inline):

    @Override
    public Terminal createTerminal() throws IOException {
        // 3 different reasons for tty-based terminal:
        //   "explicit preference", "no alternative",
        //       ("because we can" - unless "rather not")
        if (forceTextTerminal || isAwtHeadless() ||
                (hasTerminal() && !preferTerminalEmulator) ) {
            return createHeadlessTerminal(); // <--- Windows and Linus go into this branch
        }
        else {
            // while Lanterna's TerminalEmulator lacks mouse support:
            // if user wanted mouse AND set a telnetPort, and didn't
            //   explicitly ask for a graphical Terminal, then go telnet:
            if (!preferTerminalEmulator && mouseCaptureMode != null && telnetPort > 0) {
                return createTelnetTerminal();
            } else {
                return createTerminalEmulator(); // <--- App started with debugger goes into this branch
            }
        }
    }

On windows it enters createHeadlessTerminal and later fails in createWindowsTerminal with "To start java on Windows, use javaw! (see https://github.com/mabe02/lanterna/issues/335 )"

So basically what I did is replaced:

        this.terminal = new DefaultTerminalFactory().createTerminal();

with

        Terminal t;
        try {
            t = new DefaultTerminalFactory().createTerminal(); // <--- Linux and debugger use this branch
        } catch (IOException e) {
            t = new DefaultTerminalFactory().setPreferTerminalEmulator(true).createTerminal(); // <--- Windows uses this branch
        }
        this.terminal = t;

in my code, and now I can remove java/javaw switching logic and whole .bat file alltogether. As far as I tested - everything works just fine.

Are there any downsides to this approach? Maybe createTerminal() should not fail with "To start java on Windows, use javaw! (see https://github.com/mabe02/lanterna/issues/335 )" if we actually can create SwingTerminalWindow without using javaw?