java - 将控制台输出到文本文件中？ - java

Question

给定我的代码:

import java.util.Scanner;

public class AccountTest {

    public static void main(String[] args) {
        Account account1 = new Account(50.00);
        Account account2 = new Account(0.00);

        System.out.printf("account1 balance: $%.2f\n", account1.getBalance());
        System.out.printf("account2 balance: $%.2f\n\n", account2.getBalance());

        Scanner input = new Scanner(System.in);

        System.out.print("Enter withdrawal amount for account1: ");

        double withdrawalAmount = input.nextDouble();

        System.out.printf("\nsubtracting %.2f from account1 balance\n",
                withdrawalAmount);

        account1.debit(withdrawalAmount);

        System.out.printf("account1 balance: $%.2f\n", account1.getBalance());
        System.out.printf("account2 balance: $%.2f\n\n", account2.getBalance());

        System.out.print("Enter withdrawal amount for account2: ");
        withdrawalAmount = input.nextDouble();
        System.out.printf("\nsubtracting %.2f from account2 balance\n",
                withdrawalAmount);
        account2.debit(withdrawalAmount);

        System.out.printf("account1 balance: $%.2f\n", account1.getBalance());
        System.out.printf("account2 balance: $%.2f\n", account2.getBalance());
    }
}

如何将“System.out.printf”转储到文件中(转储为不删除文件内容)？或者也许为每个实例创建单独的文件。初学者如有任何帮助，我们将不胜感激。谢谢。

Answer 1

1) 您可以在运行程序时将 stdout 重定向到文件

java AccountTest >> test.txt 

2)您可以在程序开始时重新分配标准输出

    PrintStream out = new PrintStream(new FileOutputStream("test.txt", true));
    System.setOut(out);

3)你可以使用java.io.PrintWriter代替System.out

    PrintWriter out = new PrintWriter(new FileWriter("test.txt", true));
    out.printf( "account1 balance: $%.2f\n", account1.getBalance() );