I have code like this one:
@Service
class SomeClass (
private val departmentClient : DepartmentClient
) {
fun someFunction(
employee: Employee,
department: Department = departmentClient.getById(employee.departmentId)
): Unit {
here my code
}
}
data class Employee(val departmentId: Long, val id: Long)
data class Department(val id: Long)
@Service
class DepartmentClient() {
fun getById(id: Long): Department
}
When I don't pass the department parameter in someFunction, I expect that departmentClient.getById(employee.departmentId)
will be called. The problem is that in some cases I get a null pointer exception in this line, but in others, I don't. All dependencies are injected by Spring.
The function getById
is probably defined wrongly and at runtime it hits with a null-pointer-exception. Where does this function come from?
It should look like this:
class DepartmentClient() {
fun getById(id: Long): Department?
}
That would mean you need to deal with department: Department?
in here my code
.
I think this happens when You assigned a variable null value You can fix the problem like this by using '?'or '?.' (safety operator) by putting '?' after a Type (Department)
fun someFunction(
employee: Employee,
department: Department? = departmentClient.getById(employee.departmentId)
): Unit {
here my code
}
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