Jackson JSON Ignore Properties Dynamically - json

Question

I have the following classes -
Employee
public class Employee {
private String firstName ;
private String lastName ;
private String emailAddress ;
private String ssn ;
}
Payroll
public class Payroll {
// different payroll related fields
private Employee emp ;
}
HR
public class HR {
// different HR related fields
private Employee emp ;
}
Now when I serialize my Payroll class, I don't want to serialize my ssn field from Employee class.
Where as when I serialize my HR class, I don't want to serialize my emailAddress field from Employee class.
How I can dynamically exclude fields from serializing by using Jackson JSON API?

Answer 1

How I can dynamically exclude fields from serializing by using Jackson JSON API?
This seems like a prime candidate for applying JacksonJsonViews.
public class Employee {
private String firstName;
private String lastName;
#JsonView(Views.Payroll.class) private String emailAddress;
#JsonView(Views.HR.class) private String ssn;
}
public class Payroll {
// snip
#JsonView(Views.Payroll.class)
private Employee emp;
}
public class HR {
// snip
#JsonView(Views.HR.class)
private Employee emp;
}

Answer 2

You can achieve this with the help of a JsonFilter.
Annotate the class you want to filter as thus:
#JsonFilter("employeeFilter")
public class Employee {
private String firstName ;
private String lastName ;
private String emailAddress ;
private String ssn ;
}
Create a service called FilterBeanService(Or anything really)
#Service
public class FilterBeanService {
// fields is an array of field names you wish not to sned in your response
// beanFilterName is value you give when you annotage your bean class
// dataSet is the data you want to filter
public static MappingJacksonValue filterBean(String[] fields, String beanFilterName, Object dataSet ) {
SimpleBeanPropertyFilter filter = SimpleBeanPropertyFilter.serializeAllExcept(fields);
FilterProvider filterProvider = new SimpleFilterProvider().addFilter(beanFilterName, filter);
MappingJacksonValue jacksonValue = new MappingJacksonValue(dataSet);
jacksonValue.setFilters(filterProvider);
return jacksonValue;
}
}
In your controller, you can then filter fileds you do not want
#GetMapping("/whatever")
public ResponseEntity<MappingJacksonValue> getSomething(){
List<Employee> employees = eventRepo.findAll();
String[] fields = {"ssn"};
MappingJacksonValue jacksonValue = FilterBeanService.filterBean(fields, "employeeFilter", employees);
return jacksonValue;
}

Answer 3

I answered below to dynamically deserialise with customer reader. Can do similar thing with writer to ignore when serialising.
Jackson Change JsonIgnore Dynamically