How do I use the “return” value of one method in another method

问题

I am currently working on this project that plays the high low dice game. I am stuck on how to use the returned char from getHighLow and the returned int from getBet and getRoll in determineWinnings. This is my first year learning Java currently, so any help would be appreciated. Thank you in advance for any help you can give!

public static void main(String[] args) {
    Scanner keyboard = new Scanner(System.in);
    int currentPool = 100;
    getBet(keyboard, currentPool);
    getHighLow(keyboard);
    getRoll();
    >>  determineWinnings(highLow, userBet, rollSum);


}

// Given a Scanner and a current maximum amount of money, prompt the user for
// an integer representing the number of dollars that they want to bet. This
// number must be between 0 and to maximum number of dollars. If the user enters
// a number that is out of bounds, display an error message and ask again.
// Return the bet to the calling program.
private static int getBet(Scanner inScanner, int currentPool) {
    int userBet = -1;
    while (userBet == -1) {
        inScanner = new Scanner(System.in);
        System.out.println("You have $" + currentPool);
        System.out.println("Enter an amount to bet (0 to quit): ");
        userBet = inScanner.nextInt();
        if (userBet > currentPool || userBet < 0) {
            System.out.println("Your bet MUST be between 0 and " + currentPool + " dollars");
            userBet = -1;
        }
        if (userBet == 0) {
            System.out.println("You have " + currentPool + " dollars left.");
            System.out.println("Goodbye!");
        }
    }
    return userBet;
}

// Given a Scanner, prompt the user for a single character indicating whether
// they
// would like to bet High ('H'), Low ('L') or Sevens ('S'). Your code should
// accept
// either capital or lowercase answers, but should display an error if the user
// attempts
// to enter anything but one of these 3 values and prompt for a valid answer.
// Return the character to the calling program.
private static char getHighLow(Scanner inScanner) {
    Scanner keyboard = new Scanner(System.in);
    int i = 0;
    String userChoice = "";
    while (i == 0) {
        System.out.println("High, low or sevens (H/L/S): ");
        userChoice = keyboard.nextLine();
        if (userChoice.length() > 1 || (userChoice.charAt(0) != 'H' && userChoice.charAt(0) != 'h'
                && userChoice.charAt(0) != 'L' && userChoice.charAt(0) != 'l' && userChoice.charAt(0) != 'S'
                && userChoice.charAt(0) != 's')) {
            System.out.println("ERROR: You must type H, L, or S.");
        } else {
            i++;
        }
    }
    char highLow = 'N';
    if (userChoice.charAt(0) == 'H' || userChoice.charAt(0) == 'h') {
        highLow = 'H';
    } else if (userChoice.charAt(0) == 'L' || userChoice.charAt(0) == 'l') {
        highLow = 'L';
    } else {
        highLow = 'S';
    }
    return highLow;
}

// Produce a random roll of a single six-sided die and return that value to the
// calling
// program
private static int getRoll() {
    int dieOne = (int) (Math.random() * 6 + 1);
    System.out.println("Die 1 rolls: " + dieOne);
    int dieTwo = (int) (Math.random() * 6 + 1);
    System.out.println("Die 2 rolls: " + dieTwo);
    int rollSum = dieOne + dieTwo;
    System.out.println("The total of two dice is: " + rollSum);
    return rollSum;
}

// Given the choice of high, low or sevens, the player's bet and the total
// result of
// the roll of the dice, determine how much the player has won. If the player
// loses
// the bet then winnings should be negative. If the player wins, the winnings
// should
// be equal to the bet if the choice is High or Low and 4 times the bet if the
// choice
// was Sevens. Return the winnings to the calling program.
private static int determineWinnings(char highLow, int bet, int roll) {
    int highLowValue = 0;
    int winnings = 0;
    if (highLow == 'H') {
        highLowValue = 8;
    } else if (highLow == 'L') {
        highLowValue = 6;
    } else {
        highLowValue = 7;
    }
    if (roll >= 8 && highLowValue == 8) {
        winnings = bet;
        System.out.println("You won " + winnings + " dollars!");
    } else if (roll <= 6 && highLowValue == 6) {
        winnings = bet;
        System.out.println("You won " + winnings + " dollars!");
    } else if (roll == 7 && highLowValue == 7) {
        winnings = bet * 4;
        System.out.println("You won " + winnings + " dollars!");
    } else {
        winnings = -1 * bet;
    }
    return winnings;

}

回答1:

You can assign the output of each method to variable or call methods directly on determineWinnings.

plan 1)

int userBet = getBet(keyboard, currentPool);
char highLow = getHighLow(keyboard);
int roll = getRoll();
determineWinnings(highLow, userBet, roll);

plan 2)

determineWinnings(getHighLow(keyboard), getBet(keyboard, currentPool), getRoll());

回答2:

There are following approaches to get the result of one method to another.

Pass result of one method to another
Define private/static members

Better way would be passing result of one method to another method.

来源：https://stackoverflow.com/questions/52746162/how-do-i-use-the-return-value-of-one-method-in-another-method

标签

java

methods

return-value