constructor - Findbugs 在验证构造函数参数时报告已知空值的负载

Question

使用 findbugs 扫描以下代码后，它会报告 Dodgy code:NP: Load of known null value in new ....(at line where new Exception isthrowed)

有时需要在初始化对象之前检查 null。
为什么这被认为是“狡猾的”？

public class Employee{

  @Valid
  private Department dept;

  @JsonCreator
  public Employee(@JsonProperty(value = "department", required = true) Department aDepartment)
      throws EmpServiceException{
    if (aDepartment == null) {
      throw new EmpServiceException(aDepartment, "Invalid Request");
    }
    this.dept= aDepartment;
  }

Answer 1

我的猜测是 FindBugs 指出您抛出异常的那一行

throw new EmpServiceException(aDepartment, "Invalid Request");

相当于

throw new EmpServiceException(null, "Invalid Request");

并希望您使用后者。是第一个参数 EmpServiceException用 @NonNull 注释的构造函数?