java - 堆栈值未读入文件

Question

我目前正在研究以下方法:

public void addExpenditure(Stack<Double> costStack){

    try(BufferedWriter bw = new BufferedWriter(new FileWriter(f.getPath(), true))) {

        while (costStack.size() != 0)
            bw.write(costStack.pop().toString() + " ,");

    }catch(Exception e){
        e.printStackTrace();
    }

}

方法是简单地取出存储在堆栈costStack中的值并将它们写入文件中。然而，由于未知的原因，这并没有发生。

相反，每次都不会向文件写入任何内容。这很奇怪，因为这个方法完全按照其应有的方式执行，并且几乎相同:

public void addExpenditure(double amount){

    Double amount1 = amount;

    try(BufferedWriter bf = new BufferedWriter(new FileWriter(f.getPath(), true))){
        bf.write(amount1.toString() + " , ");
    }catch(IOException e){
        e.printStackTrace();
    }

}

也不会抛出任何异常。

以下是我目前用于实现此“工作”的所有方法:

import java.util.Scanner;
import java.util.Stack;

public class BudgetMain {

/*
Pre-Tax income per month: $5875
After-Tax income per month: $4112
Savings Goal per month (61% of After-Tax income): $2508.62
Expendable income per month (After-Tax income - Savings Goal Per month): $1604
 */

public static void main(String[] args){

    try {
        Budget b = new Budget();
        b.clearFile();
        System.out.println("Available funds left to spend this month: " + b.availableFundsLeft());
        Stack<Double> costStack = new Stack<>();
        costStack = takeValues(costStack);
        b.addExpenditure(costStack);
        System.out.println("Available funds left to spend this month: " + b.availableFundsLeft());
    }catch(Exception e){e.printStackTrace();}

    }


public static Stack<Double> takeValues(Stack<Double> costStack){

    System.out.println("Enter appropriate expenditures");
    Scanner stdin = new Scanner(System.in);

    while(true) {
        costStack.push(stdin.nextDouble());
        if (costStack.peek() == -1){
            costStack.pop();
            return costStack;
        }
    }


}

}

不同的类文件:

public void addExpenditure(Stack<Double> costStack){

    try(BufferedWriter bw = new BufferedWriter(new FileWriter(f.getPath(), true))) {

        while (costStack.size() != 0)
            bw.write(costStack.pop().toString() + " ,");

    }catch(Exception e){
        e.printStackTrace();
    }

}

public double availableFundsLeft(){
    try{return afterTaxIncome - savingsGoalPerMonth - 
getTotalExpenditureThisMonth();}
    catch(Exception e){e.printStackTrace();}
    return -1;
}

Answer 1

这段代码似乎有效，它创建了一个内容为 2.0 ,1.0 的 test.out 文件，

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Scanner;
import java.util.Stack;

public class BudgetMain {


    public static void main(String[] args){
        Stack<Double> stack = new Stack<>();
        stack.push(1.0);
        stack.push(2.0);
        addExpenditure1(stack, new File("test.out"));
    }


    public static void addExpenditure1(Stack<Double> costStack, File f){

        try(BufferedWriter bw = new BufferedWriter(new FileWriter(f.getPath(), true))) {

            while (costStack.size() != 0)
                bw.write(costStack.pop().toString() + " ,");

        }catch(Exception e){
            e.printStackTrace();
        }

    }
}