合併兩個賬戶

Question

這是一項家庭作業。我需要合併這兩個賬戶（acct2和acct3），並生成第三個賬戶名稱相同，賬號不同，價格爲200美元的賬戶。我也必須關閉前兩個賬戶。但這並不是真正的問題。如果我不聲明公共靜態帳戶accountConsolidate（Account acct1，Account acct2）作爲一個靜態方法，並且只是在main中創建一個對象，那麼我可以使一切正常工作。這不起作用，因爲我需要將此方法聲明爲靜態。此外，如果我確實聲明它是靜態的，我可以在if(acct1.name.equalsIgnoreCase(acct2.name) && acct1.acctNum != acct2.acctNum)中得到正確的返回值，如果我排除了其他明智的情況，它將返回null（「這兩個帳戶不能夠得到鞏固。請再次檢查標準」，不知道爲什麼。

任何幫助將是巨大的。謝謝

import java.util.Random; 

    public class Account 
    { 
     private static int numAccounts = 0; 
     private double balance; 
     private static String name; 
     private static double acctNum; 
     static Random gen = new Random(); 

    //------------------------------------------------- 
    //Constructor -- initializes balance, owner, and account number 
    //------------------------------------------------- 
     public Account(double initBal, String owner, double number) 
     { 
      balance = initBal; 
      name = owner; 
      acctNum = number; 
      numAccounts++; 
     } 

     public Account(double initBal, String owner) 
     { 
      balance = initBal; 
      name = owner; 
      acctNum = Math.abs(gen.nextDouble()); 
      numAccounts++; 
     } 

     public Account(String owner) 
     { 
      balance = 0; 
      name = owner; 
      acctNum = Math.abs(gen.nextDouble()); 
      numAccounts++; 
     } 

    //------------------------------------------------- 
    // Checks to see if balance is sufficient for withdrawal. 
    // If so, decrements balance by amount; if not, prints message. 
    //------------------------------------------------- 
     public void withdraw(double amount) 
     { 
      if (balance >= amount) 
      { 
       balance -= amount; 
      } 
      else 
       System.out.println("Insufficient funds"); 
     } 

     public void withdraw(double amount, double fee) 
     { 
      if (balance >= amount) 
       { 
        balance -= amount; 
        balance -= fee; 
       } 
      else 
       System.out.println("Insufficient funds"); 
     } 

    public String getName() 
    { 
     return name; 
    } 

    public double getNum() 
    { 
     return acctNum; 
    } 

    //------------------------------------------------- 
    // Adds deposit amount to balance. 
    //------------------------------------------------- 
     public void deposit(double amount) 
     { 
      balance += amount; 
     } 

    //------------------------------------------------- 
    // Returns balance. 
    //------------------------------------------------- 
     public double getBalance() 
     { 
      return balance; 
     } 

    // Static method to keep track of incrementing Account 
     public static int getNumAccounts() 
     { 
      return numAccounts; 
     } 

    // Close the account 
     public void close() 
     { 
      balance = 0; 
      name = "CLOSED"; 
      numAccounts--; 
     } 


    // Consolidate accounts 
     public static Account accountConsolidate(Account acct1, Account acct2) 
     { 

      if(acct1.name.equalsIgnoreCase(acct2.name) && acct1.acctNum != acct2.acctNum) 
      { 
       Account Account2 = new Account(0, acct1.name); 
       Account2.balance = acct1.getBalance() + acct2.getBalance(); 
       acctNum = Math.abs(gen.nextDouble()); 

       acct1.close(); 
       acct2.close(); 
       return Account2; 

      } 
      else 
      { 
       System.out.println("These two accounts are not able to be consolidated. Please check the criteria again"); 
       return null; 
      } 
     } 

    //------------------------------------------------- 
    // Returns a string containing the name, account number, and balance. 
    //------------------------------------------------- 
     public String toString() 
     { 
      return "Name:" + name + 
       "\nAccount Number: " + acctNum + 
       "\nBalance: " + balance; 
     } 
    } 

//************************************************************ 
//TestAccounts1 
//A simple program to test the numAccts method of the 
//Account class. 
//************************************************************ 
import java.util.Scanner; 

    public class TestAccount1 
    { 
     public static void main(String[] args) 
     { 
      String name1; 
      String name2; 
      String name3; 

      Scanner scan = new Scanner(System.in); 

      System.out.print("Please enter the name for account 1: "); 
      name1 = scan.nextLine(); 
      Account acct1 = new Account (100, name1); 
      System.out.println(acct1); 
      System.out.println("Now there are " + Account.getNumAccounts() + " accounts"); 
      System.out.println(""); 

      System.out.print("Please enter the name for account 2: "); 
      name2 = scan.nextLine(); 
      Account acct2 = new Account (100, name2); 
      System.out.println(acct2); 
      System.out.println("Now there are " + Account.getNumAccounts() + " accounts"); 
      System.out.println(""); 

      System.out.print("Please enter the name for account 3: "); 
      name3 = scan.nextLine(); 
      Account acct3 = new Account (100, name3); 
      System.out.println(acct3); 
      System.out.println("Now there are " + Account.getNumAccounts() + " accounts"); 
      System.out.println(""); 

      acct1.close(); 
      System.out.println(""); 
      System.out.println("There are now " + Account.getNumAccounts() + " accounts"); 


      System.out.println("Accounts consolidated"); 
      System.out.println(Account.accountConsolidate(acct2, acct3)); 
} 
} 

Answer 1

您的帳戶號碼是隨機生成的，但accNum是靜態的，所以每個帳戶將有創建的最後一個帳戶的帳號，因此acct1.acctNum != acct2.acctNum將永遠是fals即

您的帳戶名稱也是靜態的，因此每個帳戶都有最後創建的帳戶的帳戶名稱。

更改後，請閱讀您的編譯器錯誤。它會告訴你下一步該做什麼。考慮你將修改哪個對象的哪些變量。像acctNum = Math.abs(gen.nextDouble());將不會設置您的合併帳戶Account2的帳號。