Java repeat part of a program with if and boolean operators

Hello I'm fairly new to java and I had troubles in a little test game. So this is just a part of the code, I want that the user can repeat the part as often as he like with an while operater.

The code is here:

else if (a == 6){
        boolean InGame = true;
        while ( InGame );

        System.out.println("Glückspiel: Wer näher an der zufälligen Zahl ist gewinnt! 1-100");
        System.out.println("Spieler Eins");
        double playerOne = scan.nextDouble();
        System.out.println("Spieler Zwei");
        double playerTwo = scan.nextDouble();

        double randomValue = Math.random() * 100.0;

        // Math.abs
        double spacingOne = Math.abs(playerOne - randomValue);
        double spacingTwo = Math.abs(playerTwo - randomValue);
        System.out.println("Die Random Zahl war " + randomValue);

        if (spacingOne < spacingTwo) {
            System.out.println("Spieler Eins hat gewonnen!");
        }

        if (spacingOne > spacingTwo) {
            System.out.println("Spieler Zwei hat gewonnen!");
        }

        if (spacingOne == spacingTwo) {
            System.out.println("Unentschieden!");
        }
        System.out.println("Wenn du nochmal spielen willst schreibe 'ja' wenn nicht 'nein'");
        String PlayAgain = scan.nextLine();
        if  (PlayAgain == "nein");
        boolean inGame = false;

Well I have never worked alot with booleans due to me being new in java. Would nice if you could help me out.