Open powershell with java processbuilder and keep it opened

Question

is there some way on how to open powershell with process builder in javafx and keep it opened to execute any command anytime?

Example code(executing only one command at a time):

try {
    ProcessBuilder builder = new ProcessBuilder("cmd.exe", "/c", "powershell -Command \"Add-Type -AssemblyName System.DirectoryServices.AccountManagement; [System.DirectoryServices.AccountManagement.UserPrincipal]::Current.DisplayName\"&&exit");
    Process p = builder.start();
    BufferedReader reader = new BufferedReader(new InputStreamReader(p.getInputStream()));
    String line = null;
    while ((line = reader.readLine()) != null) {
        if (!line.trim().isEmpty()) {
            displayname = line;
        }
    }
    reader.close();
    p.waitFor();
    p.destroy();

} catch (IOException | InterruptedException ex) {
    Logger.getLogger(AccountStatus.class.getName()).log(Level.SEVERE, null, ex);
}

Reason to keep it opened: loading powershell takes maybe 3 seconds and loading for example active directory plugin takes another maybe 2 seconds everytime i want to execute some command. If there is some way on how to preload powershell and send command to processbuilder anytime it would be very helpfull, thanks for advices.

EDIT:

I have found solution here: Apache Commons exec PumpStreamHandler continuous input

Thanks to MichalVales!

With this quick sample i am able to open powershell, keep it opened, preload some module and execute any new command anytime without loading all again.

public class FXMLDocumentController implements Initializable {

private BufferedWriter writer;

@FXML
private void handleButtonAction(ActionEvent event) {

    try {
        writer.write("Import-Module ActiveDirectory -Cmdlet Get-ADUser\n");
        writer.flush();
    } catch (IOException ex) {
        Logger.getLogger(FXMLDocumentController.class.getName()).log(Level.SEVERE, null, ex);
    }

}

@FXML
private void handleButtonAction2(ActionEvent event) {
    try {
        writer.write("Get-ADUser somenamehere -Properties * | Select-Object LockedOut\n");
        writer.flush();
    } catch (IOException ex) {
        Logger.getLogger(FXMLDocumentController.class.getName()).log(Level.SEVERE, null, ex);
    }
}

@Override
public void initialize(URL url, ResourceBundle rb) {

    ProcessBuilder builder = new ProcessBuilder("powershell.exe");
    Process process;
    try {
        process = builder.start();
        writer = new BufferedWriter(new OutputStreamWriter(process.getOutputStream()));
        StreamReader outputReader = new StreamReader(process.getInputStream(), System.out);
        outputReader.start();
        StreamReader err = new StreamReader(process.getErrorStream(), System.err);
        err.start();
    } catch (IOException ex) {
        Logger.getLogger(FXMLDocumentController.class.getName()).log(Level.SEVERE, null, ex);
    }

}

}

StreamReader code can be found on link from MichalVales

EDIT2:

I was trying to pass czech characters with any writer, but without success. I think that its impossible to pass czech characters like "ěščřžýáíé" to powershell without changing system locale, but i dont want to do it. I have tried processbuilder, apache exec, all failed, but i have found super library which works and is really easy to use: jPowerShell

So if you have problems with keeping powershell alive or problem with characters, this is the best solution.