bankaccount.java

来自「Java 入门书的源码」· Java 代码 · 共 57 行

//Copyright (c) 1998, Arthur Gittleman
//This example is provided WITHOUT ANY WARRANTY either expressed or implied.

/* Revision of Example 2.9, 
 * changing type of balance to double
 * adding withdraw method
 * overloading BankAccount constructor
 */

import iopack.Io;
public class BankAccount {
  private double balance;                                                                 

  public BankAccount()   {                                                                    
    balance = 0;
  }

  public BankAccount(double initialAmount) {
    balance = initialAmount;
  }

  public void deposit(double amount) {                                             
    balance += amount;
  }

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

  public double getBalance() {                                                         
    return balance;
  }

  public static void main (String [ ] args) {                                         
    BankAccount myAccount = new BankAccount(25.00);              
    System.out.print("My balance = ");
    Io.println$(myAccount.getBalance());
    myAccount.deposit(700.00);                                                          
    System.out.print("My balance = ");
    Io.println$(myAccount.getBalance());
    myAccount.withdraw(300.00);
    System.out.print("My balance = ");
    Io.println$(myAccount.getBalance());
    myAccount.withdraw(450.00);
    System.out.print("My balance = ");
    Io.println$(myAccount.getBalance());
    BankAccount  yourAccount = new BankAccount();                                            
    yourAccount.deposit(1234.56);                                                   
    System.out.print("Your balance = ");
    Io.print$(yourAccount.getBalance());
    Io.readString("Press any key to exit");   // Added for IDE use
  }
}