建立exception包，建立Bank类，类中有变量double balance表示存款,Bank类的构造方法能增加存款，Bank类中有取款的发方法withDrawal(double dAmount),
当取款的数额大于存款时,抛出InsufficientFundsException,取款数额为负数，抛出NagativeFundsException,如new Bank(100),表示存入银行100元，
当用方法withdrawal(150)，withdrawal(-15)时会抛出自定义异常。
package exception;
public class Bank {
// 中有变量double balance表示存款,
// Bank类的构造方法能增加存款，
// Bank类中有取款的发方法withDrawal(double dAmount),
// 当取款的数额大于存款时,抛出InsufficientFundsException,
// 取款数额为负数，抛出NagativeFundsException,
double balance;
public double getBalance() {
return balance;
}
public void setBalance(double balance) {
this.balance = balance;
}
public Bank(double balance)
{
System.out.println("存款金额为："+(balance));
}
public void withDrawal(double dAmount)
{
if(dAmount>balance)
{
try {
throw new InsufficientFundsException();
}
catch (InsufficientFundsException e)
{
e.printStackTrace();
}
}
if(dAmount<0)
{
try {
throw new NagativeFundsException();
} catch (NagativeFundsException e) {
e.printStackTrace();
}
}
}
}
package exception;
public class InsufficientFundsException extends Exception {
@Override
public String getMessage() {
return "存款余额不足！";
}
}
package exception;
public class NagativeFundsException extends Exception {
@Override
public String getMessage() {
return "取款数额不能为负数!";
}
}
package exception;
public class test {
public static void main(String[] args) {
// TODO 自动生成的方法存根
// new Bank(100),表示存入银行100元，
// 当用方法withdrawal(150)，
// withdrawal(-15)时会抛出自定义异常
Bank b=new Bank(100);
b.withDrawal(150);
b.withDrawal(-15);
}
}
