Question

我正在开发一个程序，该程序从包含银行帐户列表的文件中读取。我一直遇到IndexOutOfBoundsException错误，我不知道为什么。当我把银行账户直接放在代码中（而不是从文件中读取）时，它工作得很好，这使我相信我的while循环在某处搞砸了。我怀疑它没有正确循环但我并不积极。不幸的是，我没有很多关于while循环的经验。任何帮助将不胜感激，谢谢：）

我正在阅读的文件，按照帐户类型/名称/价值/费率的顺序列出：

1,Waterford Ellingsworth,4350.0,0.002
2,Bethanie Treadwell,500.0,0.35
3,Ira Standish,50000,0.1,59,0.1

实际程序本身：

 Scanner infile = new Scanner("‪C:/Users/Josh/Desktop/prog5input.csv");
    while (infile.hasNextLine()) {
        Scanner s2 = new Scanner(infile.nextLine()); // put string from file into second Scanner object
        s2.useDelimiter(",");
        if (s2.hasNextInt()) {
            int type = s2.nextInt(); 
            if (type == 1) {
                String accountHolder = s2.next();
                double accountInitial = s2.nextDouble();
                double accountRate = s2.nextDouble();
                bank.addNewAccount(new SavingsAccount(accountHolder, accountInitial, accountRate));
                // read fields for Type 1 accounts and create new Type 1 object
            }
            else if (type == 2) {
                String accountHolder = s2.next();
                double accountInitial = s2.nextDouble();
                double accountCostPerMonth = s2.nextDouble();
                bank.addNewAccount(new CheckingAccount(accountHolder, accountInitial, accountCostPerMonth));
            }
            else if (type == 3) {
                String accountHolder = s2.next();
                double accountInitial = s2.nextDouble();
                double accountRate = s2.nextDouble();
                int disbursementAge = s2.nextInt();
                double earlyWithdrawalPenalty = s2.nextDouble();
                bank.addNewAccount(new IRAAccount(accountHolder, accountInitial, accountRate, disbursementAge, earlyWithdrawalPenalty));
            }
        } //ends if statement s2.hasNextInt()
        // now go to top of loop, check infile to see if there is another line to read
    } //ends while loop

编辑包含输出：

Creating accounts...

Performing transactions...
Exception in thread "main" java.lang.IndexOutOfBoundsException: Index: 0, Size: 0
    at java.util.ArrayList.rangeCheck(Unknown Source)
    at java.util.ArrayList.get(Unknown Source)
    at Bank.getAccountByIndex(Bank.java:28)
    at BankDriverFileInput.main(BankDriverFileInput.java:58)

这是我整个计划的链接：https://drive.google.com/drive/folders/0BysdkYqrEP7kazNhMXpQSzd4bUE?usp=sharing

Answer 1

替换

swiper.slideTo(activeSlide);

带

Scanner infile = new Scanner("‪C:/Users/Josh/Desktop/prog5input.csv");

作为您的代码，扫描仪的输入流将是字符串＆＃34; c：....＆＃34;而不是它代表的文件。

Answer 2

我下载了你的谷歌驱动程序，它对我来说很有魅力，有以下变化..

Scanner infile = new Scanner(new FileInputStream("‪C://Users//Josh//Desktop//prog5input.csv"));

确保您在此处指定了正确的文件路径..

我的样本输出供您参考：

计划5，Josh Correia，cssc0491 创建帐户...... Waterford Ellingsworth4350.00.002Customer：Waterford Ellingsworth，储蓄账户1余额：$ 4350.00 客户：Bethanie Treadwell，支票账户2余额：$ 500.00 客户：Ira Standish，IRA储蓄账户3余额：$ 50000.00，支付年龄= 59，提前取款罚款= 0.1

执行交易...... 储蓄账户1余额：4550.00美元支票账户2余额：$ 286.87 IRA储蓄账户3余额：$ 50000.00，支付年龄= 59，提前取款罚款= 0.1

更新帐户... 储蓄账户1余额：4559.10美元支票账户2余额：$ 286.52 IRA储蓄账户3余额：55000.00美元，支付年龄= 59，提前提款罚款= 0.1

while循环读取csv文件超出范围

2 个答案:

我的样本输出供您参考：