java - 如何修复我的子类循环，使其在主类中调用时仅循环一次？

Question

运行程序(在 NetBeans 8.2 中构建和运行)时，它只会运行一次子类循环，而它应该运行 3 次，每个用户输入的变量值运行一次。

我尝试调整 m[0].length，将其替换为:m.length、>4、>3、=>3、=>4，按照 NetBeans 建议转换 for 循环:for (double[] m1:m)。

public class ConversionRate {

    public static void main(String[] args) {

        //scanner for user input for variables
        Scanner input = new Scanner(System.in);

        //declare variables to be used
        String currency;
        double [][] m = new double[3][3];

        //user input for starting rate to be converted
        System.out.print("Enter USD or EURO as the starting currency to be " +
                "converted: ");        
        currency = input.nextLine();

        System.out.println("Enter " + m.length + " values to be converted, " + 
                "adding a space between each value: ");

        for (int i = 0; i < m.length; i++){
            for (int j = 0; j == 0; j++){
                m[i][j] = input.nextDouble();
            }
        }
        if (currency.equalsIgnoreCase("USD")){
        for (int k = 0; k < m.length; k++){
            System.out.println("Converted Value        " + 
                "  Conversion Rate");
            System.out.println("=========================================");
            System.out.println("  " + convertedUs(m,k) +
                    "                      " + conversionRateUs(m,k));
        }
        }
        else if (currency.equalsIgnoreCase("Euro")){
        for (int k = 0; k < m.length; k++){
            System.out.println("Starting Value      Converted Value      " + 
                "  Conversion Rate");
            System.out.println("=========================================" + 
                "==================");
            System.out.println("                         " + convertedEuro(m,k) +
                    "                      " + conversionRateEuro(m,k));
                }
        } else {
            System.out.println("Invalid selection, please try again.");
        }
    } 

public static double conversionRateUs (double [][] m, int columnIndex){

        double conversionRateUs = 0.02; 
        double value2 = 0.00;

        for (int i = 0; i < m[0].length; i++){
            value2 = m[i][columnIndex] * (0.02 * 100) / 100;
        }      
            return value2;

}

public static double conversionRateEuro (double [][] m, int columnIndex){

        double conversionRateEuro = 0.08; 
        double value2 = 0.00;

        for (int i = 0; i < m[0].length; i++){
            value2 = m[i][columnIndex] * (0.08 * 100) / 100;
        }      
            return value2;
}

预期结果将计算总转化率和转化“税”率，以对用户输入的每个值进行收费，目前仅显示第一个值。

Answer 1

我确实解决了我的问题，当我只需要使用一维数组时，我试图使用多维数组。现在正在处理信息格式，但我得到了计算和输出，最终可以正常工作:

https://gist.github.com/sometowngeek/0eaf0dcec5e7318f24f66347ef3748b1