现有人编写了帐号类Account,用于管理个人的存款余额, public Account{ private double balan

Question

现有人编写了帐号类Account，用于管理个人的存款余额， public Account{ private double balance; //帐号余额，余额最低为0 public double getBalance(){ return balance; } Public void setBalance(double b){ balance=b; } public double withdrawl(double money) throws Exception { //取款，money如果为负数或余额不足，抛出异常 } } 请用错误推测法为withdrawl()函数至少设计3个测试用例，并写出基于Junit的测试代码 。

Answer 1

正确答案：
publicclassTestSampleextendsTestCase{publicvoidtestWithDrawlEqual(doublemoney){Accounta=newAccount();a.setAccount(5);doubleresult=a.withdrawl(5);Assert.assertEquals(0,result);}publicvoidtestWithDrawlNegative(){try{Accounta=newAccount();a.setAccount(5);doubleresult=a.withdrawl(-1);fail();}catch(Exceptionerr){Assert.assertTrue(true);}}publicvoidtestWithDrawlTooMuch(){try{Accounta=newAccount();a.setAccount(5);doubleresult=a.withdrawl(8);fail();}catch(Exceptionerr){Assert.assertTrue(true);}}}