对于此代码，我想模拟老虎机并将游戏的用户名和分数放在名为scores.txt的文本文件中，这样如果用户选择选项2，他们就可以查看他们的分数。
但是，我在FileWriter语句中收到了很多错误（行到了最后并标有注释），特别是我不理解为CP1252编码的不可映射字符。从我检查的所有地方，当有人使用像日语字符这样的不同字符时，我看到这个错误 - 那么为什么会出现这样的错误呢？我查看了代码示例，但我还没有学过流，尝试捕获或缓冲。
使用filewriter和printwriter 有人可以向我解释如何创建文件编写器对象并将其正确传递给printwriter对象，以及如何正确读取该文件中的数据（scores.txt） 。非常感谢，如果这是一个简单的错误，那就很抱歉。
问题的具体领域：
File file = new File(“scores.txt”); //illegal start of expression
if (!file.exists())
{
file.createNewFile();
}
Scanner inputFile = new Scanner(file);
String line = inputReader.nextLine();
FileWriter fwriter = new FileWriter(“scores.txt”, true); //this is where the error CP1252,
PrintWriter outputWriter = new PrintWriter(file);
outputFile.println(username);
outputFile.println(userFinalTotal);
}
else if (option == 2)
{
if (file.exists())
{
while (inputFile.hasNext())
{
username = inputFile.nextLine();
System.out.println ("Name\n------\n" + name + "\n");
userFinaltotal = inputFile.nextDouble();
System.out.printf("Scores\n------\n$%.2f\n", userFinalTotal);
System.out.println();
inputReader.close();
}
以下是查看变量来源的完整程序。
import java.util.Scanner;
import java.util.Random;
import java.io.*;
public class SlotsMachine
{
public static void main(String[] args) throws IOException
{
int number;
System.out.println ("Welcome to the Slot Machine Simulator!");
System.out.println ("\nActions\n1. Start a new game\n2. Scores\n3. Exit");
System.out.print ("\nPlease select an action: ");
Scanner keyboard = new Scanner(System.in);
int option = keyboard.nextInt();
while (option != 1 && option != 2 && option != 3)
{
System.out.print ("\nThat is not an option. Please select an item number between 1-3: ");
option = keyboard.nextInt();
break;
}
if (option == 1)
{
String username;
double startingTotal = 100.0;
double userTotal = startingTotal;
System.out.print ("\nBefore the game begins, please enter your name: ");
username = keyboard.next( );
System.out.print ("\nGame start! You will begin with $100.00. Enter a negative value to quit the game. Good luck, " + username + "!");
do
{
double bet = keyboard.nextDouble();
bet = 0.0;
userTotal = startingTotal - bet;
System.out.print ("You currently have: " + startingTotal + "\nHow much would you like to bet?");
double winnings = 0.0;
double userFinalTotal = 0.0;
if ((bet < 0) || (userFinalTotal <= 0))
{
break;
}
while (bet > userFinalTotal)
{
System.out.print("\nYour bet is greater than your current total. Please enter a valid amount: ");
bet = keyboard.nextDouble();
}
Random generator = new Random();
int slot1 = generator.nextInt(6);
keyboard.nextLine();
int slot2 = generator.nextInt(6);
int slot3 = generator.nextInt(6);
String firstSlot = "";
switch (slot1)
{
case 0:
firstSlot = "Cherries";
break;
case 1:
firstSlot = "Oranges";
break;
case 2:
firstSlot = "Plums";
break;
case 3:
firstSlot = "Bells";
break;
case 4:
firstSlot = "Melons";
break;
case 5:
firstSlot = "Bars";
break;
}
String secondSlot = "";
switch (slot2)
{
case 0:
secondSlot = "Cherries";
break;
case 1:
secondSlot = "Oranges";
break;
case 2:
secondSlot = "Plums";
break;
case 3:
secondSlot = "Bells";
break;
case 4:
secondSlot = "Melons";
break;
case 5:
secondSlot = "Bars";
break;
}
String thirdSlot = "";
switch (slot3)
{
case 0:
thirdSlot = "Cherries";
break;
case 1:
thirdSlot = "Oranges";
break;
case 2:
thirdSlot = "Plums";
break;
case 3:
thirdSlot = "Bells";
break;
case 4:
thirdSlot = "Melons";
break;
case 5:
thirdSlot = "Bars";
break;
}
System.out.println ("-------------------------------");
System.out.println ("" + firstSlot + " " + secondSlot + " " + thirdSlot);
System.out.print ("-------------------------------");
if (slot1 == slot2 && slot1 == slot3)
{
winnings = bet * 3;
userFinalTotal = userTotal + winnings;
System.out.printf ("\nNumber of matches: 3. You win: $%.2f", winnings);
System.out.printf ("\nYou currently have: $%.2f", userFinalTotal);
}
else if ((slot1 == slot2 && slot2 != slot3) || (slot1 == slot3 && slot1 != slot2) || (slot2 == slot3 && slot3 != slot1))
{
winnings = bet * 2;
userFinalTotal = userTotal + winnings;
System.out.printf ("\nNumber of matches: 2. You win: $%.2f", winnings);
System.out.printf ("\nYou currently have: $%.2fn", userFinalTotal);
}
else
{
System.out.printf ("\nNumber of matches: 0. You win: $%.2f", winnings);
System.out.printf ("\nYou currently have: $%.2f", userFinalTotal);
}
} while (userTotal > 0);
File file = new File(“scores.txt”); //illegal start of expression
if (!file.exists())
{
file.createNewFile();
}
Scanner inputFile = new Scanner(file);
String line = inputReader.nextLine();
FileWriter fwriter = new FileWriter(“scores.txt”, true); //this is where the error CP1252
PrintWriter outputWriter = new PrintWriter(file);
outputFile.println(username);
outputFile.println(userFinalTotal);
}
else if (option == 2)
{
if (file.exists())
{
while (inputFile.hasNext())
{
username = inputFile.nextLine();
System.out.println ("Name\n------\n" + name + "\n");
userFinaltotal = inputFile.nextDouble();
System.out.printf("Scores\n------\n$%.2f\n", userFinalTotal);
System.out.println();
inputReader.close();
}
}
else
{
System.out.println("There are no scores to display at this time.");
}
System.out.println("Actions:");
System.out.print("1. Start a new game\n2. View scores\n3. Exit ");
System.out.println("Please select an action: ");
option = keyboard.nextInt();
}
else if (number == 3)
{
System.out.print ("\nGoodbye!");
System.exit(0);
}
}
}
答案 0 :(得分：0)
现在编译，唯一的问题是它多次打印得分 import java.util.Scanner; import java.util.Random; import java.io。*;
public class Slot3
{
public static void main(String[] args) throws IOException
{
System.out.println ("Welcome to the Slot Machine Simulator!");
int option = 0;
//if the user selects a 1 or 2 (does not want to exit) then this loop will run
do
{
System.out.println ("\nActions\n1. Start a new game\n2. Scores\n3. Exit");
System.out.print ("\nPlease select an action: ");
Scanner keyboard = new Scanner(System.in);
option = keyboard.nextInt();
keyboard.nextLine();
while (option != 1 && option != 2 && option != 3)
{
System.out.print ("\nThat is not an option. Please select an item number between 1-3: ");
option = keyboard.nextInt();
keyboard.nextLine();
}
//this will occur if the user selects 1 to play the game
if (option == 1)
{
double money = 100.00;
double bet = 0.00;
double winnings = 0.00;
double score = 0.00;
int count = 0;
System.out.print ("\nBefore the game begins, please enter your name: ");
String username = keyboard.nextLine();
System.out.print ("\nGame start! You will begin with $100.00. Enter a negative value to quit the game. Good luck, " + username + "!");
System.out.printf("\nYou currently have $%.2f.", 100.00);
do
{
System.out.printf("\n\nHow much would you like to bet? ");
bet = keyboard.nextDouble();
if ((bet < 0) || (money <= 0))
{
break;
}
while (bet > money)
{
System.out.print("\nYour bet is greater than your current total. Please enter a valid amount: ");
bet = keyboard.nextDouble();
}
//create random numbers
Random generator = new Random();
int slot1 = generator.nextInt(6);
int slot2 = generator.nextInt(6);
int slot3 = generator.nextInt(6);
String firstSlot = "";
switch (slot1)
{
case 0:
firstSlot = "Cherries";
break;
case 1:
firstSlot = "Oranges";
break;
case 2:
firstSlot = "Plums";
break;
case 3:
firstSlot = "Bells";
break;
case 4:
firstSlot = "Melons";
break;
case 5:
firstSlot = "Bars";
break;
}
String secondSlot = "";
switch (slot2)
{
case 0:
secondSlot = "Cherries";
break;
case 1:
secondSlot = "Oranges";
break;
case 2:
secondSlot = "Plums";
break;
case 3:
secondSlot = "Bells";
break;
case 4:
secondSlot = "Melons";
break;
case 5:
secondSlot = "Bars";
break;
}
String thirdSlot = "";
switch (slot3)
{
case 0:
thirdSlot = "Cherries";
break;
case 1:
thirdSlot = "Oranges";
break;
case 2:
thirdSlot = "Plums";
break;
case 3:
thirdSlot = "Bells";
break;
case 4:
thirdSlot = "Melons";
break;
case 5:
thirdSlot = "Bars";
break;
}
System.out.println ("\n-------------------------------");
System.out.printf ("%-12s%-10s%5s\n", firstSlot , secondSlot , thirdSlot);
System.out.print ("\n-------------------------------");
//check how many of the slots match to calculate the winnings
if (slot1 == slot2 && slot1 == slot3)
{
winnings = bet * 3;
money -= bet;
score = money + winnings;
System.out.printf ("\nNumber of matches: 3. You win: $%.2f", winnings);
System.out.printf("\nYou currently have: $%.2f", score);
}
else if ((slot1 == slot2 && slot2 != slot3) || (slot1 == slot3 && slot1 != slot2) || (slot2 == slot3 && slot3 != slot1))
{
winnings = bet * 2;
money -= bet;
score = money + winnings;
System.out.printf ("\nNumber of matches: 2. You win: $%.2f", winnings);
System.out.printf("\nYou currently have: $%.2f", score);
}
else
{
winnings = bet * 0;
money -= bet;
score = money + winnings;
System.out.printf ("\nNumber of matches: 0. You win: $%.2f", winnings);
System.out.printf("\nYou currently have: $%.2f", score);
}
} while ((bet > 0) && (money > 0));
FileWriter fwriter = new FileWriter("scores.txt", true);
PrintWriter outputWriter = new PrintWriter(fwriter);
outputWriter.printf("\n\n%1s%15s" , "Name" , "Score");
outputWriter.printf ("\n\n%1s%15s" , "----" , "-----");
outputWriter.printf ("\n\n%1s%15s" , username , score);
outputWriter.close();
System.out.println("\n\nGame over! Your score has been written to scores.txt, " + username + "!");
} //end of actions for select option 1
//option 2 user wants to read their scores
if (option == 2)
{
File myFile = new File("scores.txt");
//if there are no scores to read
if (!myFile.exists())
{
System.out.println("There are no scores to display at this time.");
continue;
}
File file = new File("scores.txt");
Scanner inputFile = new Scanner(file);
while (inputFile.hasNext())
{
String username = inputFile.nextLine();
System.out.println(username);
}
inputFile.close();
} //close option 2
} while (option != 3); //close 1st do-while loop
if (option == 3)
{
System.out.print ("\nGoodbye!");
System.exit(0);
}
}
}