Ale*_*Man 2 java lambda throwable java-8 supplier
我有两个函数调用 Employee 和 Address DAO 类,我在其中检查员工姓名或地址是否已被使用
为了使检查和抛出异常通用,我创建了以下通用函数
checkOrElseThrow在CommonUtil.java
public static <R, C, T extends Throwable> R checkOrElseThrow(R rtn, C chk, Supplier<? extends T> ex) throws T
{
if (chk != null)
{
throw ex.get();
}
return rtn;
}
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上面的通用函数在EmployeeDAO.java和AddressDAO.java 中被调用,如下所示
checkAndReturnEmployee在EmployeeDAO.java
public Employee checkAndReturnEmployee(Employee employee) {
return checkOrElseThrow(
employee,
employee.getAddressName(),
() -> new EntityNotFoundException("Employee already in use for another address"));
}
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checkAndReturnAddress在AddressDAO.java
public Address checkAndReturnAddress(Address address) {
return checkOrElseThrow(
address,
address.getEmployeeName(),
() -> new EntityNotFoundException("Address already in use for another address"));
}
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我的解决方案工作正常,但我想知道是否有其他更好的方法来重写我编写的通用函数(checkOrElseThrow)
写这个的最好方法是不写。
public Employee checkAndReturnEmployee(Employee employee) {
if (employee.getAddressName() == null) {
throw new EntityNotFoundException("Employee already in use for another address"));
}
return employee;
}
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上面的代码同样简短,但更具可读性。条件是什么,不满足时会发生什么就更清楚了。
您的自定义函数仅用于尝试为 Java 创建一种新语法,其他人不会理解这种语法,您可能很快也会忘记。