我有一個名為 savingAccount 的對象，當我在 main 上創建兩個這種類型的對象時，我可以設置用戶初始帳戶余額。當我創建第一個對象時，初始值設置為 3000，當我創建第二個對象時，我的第一個和第二個對象的初始值都設置為 2000首先，我認為這與公共方法和類有關，但我將它們全部設置為私有、受保護等，問題仍然存在。這是我的對象：public class SavingsAccount {private static double annualInterestRate = 0;private static double savingsBalance = 0;private static double monthlyInterest = 0;SavingsAccount(double savingsBalance){    this.savingsBalance = savingsBalance;}void setAnnualInterestRate(double annualInterestRate){    this.annualInterestRate = annualInterestRate;}private static void updateSavingsBalance(){    savingsBalance = savingsBalance + monthlyInterest;}double getSavingsBalance(){    return savingsBalance;}}這是我的司機：    SavingsAccount saver1 = new SavingsAccount(3000.00);    System.out.println("User 1 balance: " + saver1.getSavingsBalance()); // 3000    SavingsAccount saver2 = new SavingsAccount(2000.00);    System.out.println("User 2 balance: " + saver2.getSavingsBalance()); // 2000    //2000 for both now    System.out.println("User 1 balance: " + saver1.getSavingsBalance());    System.out.println("User 2 balance: " + saver2.getSavingsBalance());