objectmapper only serialize specific fields

Question

I want to write a function that only serializes a POJO with given implicit field names.

For example,

class Car{
    public int id;
    public String type;
    public Manufacture manufacture;
}

Class Manufacture{
   public int id;
   public String name;
}

if I want to serialize a Car object with a given list(i.e. [Car.id, Car.Manufacture.name]) Then I want to get

{
    Car:{
        id: xxx,
        Manufacture: {
            name: xxx
        }
    }
}

Another example, given list = [Car.type]
Then I should get

{
    Car:{
        type: xxx
    }
}

I am currently trying to override the serializeAsField method to check if the field is in the given list, but the problem here is that I don't know the depth, then I cannot correctly compare the current field with the list.

How could I achieve it? Are there any other ways?

What is your goal? Can you provide an example of what you get vs. what you expected? The question is not clear. — tucuxi, Oct 26 '21 at 10:19
How do you currently serialize your data as JSON? Which API are you using? Please [edit] your question to include the relevant source code you have, if possible as a [mcve]. — Progman, Oct 26 '21 at 18:25

DwB · Accepted Answer · 2021-10-26T19:10:08.870

2

Mark the unwanted fields with the @JsonIgnore annotation.

On-the-fly filtering
Here is a Baeldung article that discusses using a filter to determine which fields are serialized: https://www.baeldung.com/jackson-serialize-field-custom-criteria

I suspect that is the answer you want.

edited Oct 26 '21 at 19:10

answered Oct 26 '21 at 17:24

DwB

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if the unwanted fields are implicit – uyyFactorio Oct 26 '21 at 17:52
There is no magic. You must identify what you want and what you dont want. – DwB Oct 26 '21 at 17:56
The wanted fields are generated in runtime, I believe I should override some methods to achieve it. – uyyFactorio Oct 26 '21 at 18:03

objectmapper only serialize specific fields

1 Answers1