使用同一类中的多个方法计算折扣

Question

我知道我的main方法中没有任何东西，所以没有任何东西会执行，这是作业的第二部分。

我的问题是，我在调用computeNumCases方法的computeDiscount方法中遇到错误。我得到的错误是

variable numCases might not have been initialized

所以我需要帮助找出错误。

此外，computeCost方法中的帮助也非常有用。

 public class Customer {
 private String customerLastName;
 private String candyType;
 private int numCandyBars;
 private double costPerBar;
 private int NUMBERPERCASE = 12;

 public static void main(String[] args) {

 }

 public Customer() {

 }

 public Customer(String name, String type, int numCandyBars, double costPerBar) {
  //this.name = name;
  candyType = type;
  this.numCandyBars = numCandyBars;
  this.costPerBar = costPerBar;
 }

 public static double getCostPerBar(double costPerBar) {
  return costPerBar;
 }

 public static int getNumCandyBars(int numCandyBars) {
  return numCandyBars;
 }

 public String getCandyType() {
  return candyType;
 }

 public String GetCustomerLastName() {
  return customerLastName;
 }

 public void setCustomerLastName(String name) {
  this.customerLastName = name;
 }

 public void setNumCandyBars(int num) {
  this.numCandyBars = num;
 }

 public void setCandyType(String candyType) {
  this.candyType = candyType;
 }

 public void setCostPerBar(double cost) {
  costPerBar = cost;
 }

 public int computeNumCases(int numCases) {
  numCases = numCandyBars / NUMBERPERCASE;
  return numCases;
 }

 public int computeNumIndividuals(int numIndividuals) {
  numIndividuals = numCandyBars % NUMBERPERCASE;
  return numIndividuals;
 }

 public int computeDiscount(int discount) {
  int numCases = computeNumCases(numCases);
  if (numCases < 20)
   discount = 100;
  else if (numCases < 50)
   discount = 85;
  else
   discount = 75;
  return discount;
 }

 public double computeCost(double totalCost) {
  return computeNumCases(numCases) * getCostPerBar(costPerBar) * (NUMBERPERCASE * discount / 100.00) + computeNumIndividuals(numIndividuals) * getCostPerBar(costPerBar);
 }
}