问题是我不知道如何存储来自控制台的输入。
这是我的密码：

for (int j = 0; j < arr1.length; j++) {
    System.out.println("");
    System.out.print("Select product code:        ");
    arr1[j] = reader.next();

    if (arr1[j].contains("A001")){
        mouse = 100.00;
        System.out.print("Enter quantity:               ");
        qty = reader.nextInt();
        amount = qty * mouse;
        System.out.print("Amount:\t\t\t    " + amount);
    }
    if (arr1[j].contains("A002")) {
        monitor = 2500.00;
        System.out.print("Enter quantity:               ");
        qty = reader.nextInt();
        amount = qty * monitor;
        System.out.print("Amount:\t\t\t    " + amount);
    }
    if (arr1[j].contains("A003")) {
        keyboard = 200.00;
        System.out.print("Enter quantity:               ");
        qty = reader.nextInt();
        amount = qty * keyboard;
        System.out.print("Amount:\t\t\t    " + amount);
    }
    if (arr1[j].contains("A004")) {
        flashdisk = 300.00;
        System.out.print("Enter quantity:               ");
        qty = reader.nextInt();
        amount = qty * flashdisk;
        System.out.print("Amount:\t\t\t    " + amount);
    }
    if (arr1[j].contains("A005")) {
        harddisk = 1500.00;
        System.out.print("Enter quantity:               ");
        qty = reader.nextInt();
        amount = qty * harddisk;
        System.out.print("Amount:\t\t\t    " + amount);
    }

这里的代码必须是显示存储数据结果的代码行。

System.out.println("");
System.out.print("Add item (y/n) " );
yn = reader.next().charAt(0);

if (yn == 'y' || yn == 'Y') {           
    continue;
}       
else if (yn == 'n' || yn == 'N') {          
    System.out.println("Code\tDescription\tUnit Price\tQuantity\tAmount");
    System.out.print(arr1[j]);
    if (arr1[j].contains("A001")) {
        System.out.print("\tMouse");
        System.out.print("\t\t"+mouse);
        System.out.print("\t\t"+qty);
        System.out.print("\t\t"+amount);

        if (arr1[j].contains("A002")) {
            System.out.print("\t\nMonitor");
            System.out.print("\t\t"+mouse);
            System.out.print("\t\t"+qty);
            System.out.print("\t\t"+amount);
        }
    }
}

示例输入必须是：

Select product code: A004
Enter quantity: 2
Amount: 800
add item(y/n)?: y

Select product code: A001
Enter quantity: 1
Amount: 100
add item(y/n)?: n

然后它将被存储在一个数组中，这将是结果，但是我没有得到两个输入数组，而是只得到第二个输入数组，而不是两个。

Code    Description Unit Price  Quantity    Amount
A001    Mouse       100.0       1           100.0