bank.java

JAVA的银行系统。采用java语言编写。有简单的功能

package Bank;

//Define the bank 银行

class Bank{
//Perform a transaction  执行一个事务：借款或存款
	 public void doTransaction(Transaction transaction){		//同步方法，把操作帐户的方法声明为synchronized
																//这样当一个职员对帐号进行操作时，会阻止另一个职员的介入。
		 int balance = transaction.getAccount().getBalance(); 	//Get current balance 获取帐号的余额
	
	    switch(transaction.getTransactionType()){				//switch()多分支语句
	    
			case Transaction.CREDIT:	//Credits require a lot of checks.... 存款业务
				
				synchronized(transaction.getAccount()){			//synchronized   对存款业务同步
					try{
					    Thread.sleep(100);
					}catch(InterruptedException e){
				            System.out.println(e);
					}
				    balance = transaction.getAccount().getBalance();
					balance += transaction.getAmount();				//Increment the balance
					break;											//使用break跳出。
				}
				
				
			case Transaction.DEBIT:				//Debits require even more checks...  借款业务
				
				synchronized(transaction.getAccount()){			//synchronized  对取款业务同步
					try{
					    Thread.sleep(150);
					}catch(InterruptedException e){
					    System.out.println(e);
					}
					balance = transaction.getAccount().getBalance();
					balance -= transaction.getAmount();				//Decrement the balance
					break;
				}
			default:
			    System.out.println("Invalid transaction");
			    System.exit(1);
	    } 
	   
	    transaction.getAccount().setBalance(balance);			//Restore the account balance
	}
}