checkbook.java

Java程序设计技巧与开发实例附书源代码。

public class CheckBook
{
   private final static int MAX_TRANSACTIONS = 500;
   private Transaction transactions[] = new Transaction[MAX_TRANSACTIONS];
   private double balance = 0;
   private int numTransactions = 0;

   public CheckBook(double startBalance)
   {
      add(new Adjustment("Starting balance", startBalance));
   }

   public void add(Transaction aTransaction)
   {
      if (numTransactions < MAX_TRANSACTIONS)
      {
         transactions[numTransactions] = aTransaction;
         balance += aTransaction.getAmount();
         numTransactions++;
      }
      else
      {
         System.out.println("\nMaximum number of transactions reached\n");
      }
   }

   public void showCheckBook()
   {
      System.out.println("\n=> Transaction:\t" + numTransactions);
      System.out.println("=> Balance:\t" + balance + "\n");
   }

   public void list()
   {
      showCheckBook();
      for (int i = 0; i < numTransactions; i++)
      {
         transactions[i].showTransaction();
      }
   }
}