Sonar showing issue for private fields of DTO class

Question

I have this DTO class:

class DTO{
    private String a;

    public DTO(String a){
        this.a = a;
    }
}

I am JSON serializing this class using Gson and sending it over to other application.

I don't need getters for this class. For this class sonar is showing following issue:

"Remove this unused "a" private field."

Should I ignore this sonar issue or there is another ideal way to change my code to eliminate this sonar error?

Refer https://stackoverflow.com/questions/12135939/how-to-make-sonar-ignore-some-classes-for-codecoverage-metric to exclude some code coverage — Bhavesh, Oct 27 '17 at 09:34

janos · Accepted Answer · 2023-07-12T18:05:51.503

2

The issue raised by SonarQube is a false positive in this example. Your best course of action is to mark it as such on SonarQube.

If your DTO files follow a consistent naming pattern, then it could also be interesting to configure SonarQube to ignore this issue in those files by default.

edited Jul 12 '23 at 18:05

answered Oct 27 '17 at 09:32

janos

120,954
29
226
236

The documentation link is no more accessible, feel free to amend/delete it – Ikbel Jul 12 '23 at 07:37

score 0 · Answer 2 · answered Oct 27 '17 at 09:38

In order to prevent SonarQube false positives for your DTOs you could use AutoValue as a library to create DTOs:

@AutoValue
@AutoGson(autoValueClass = AutoValue_DTO.class)
public abstract class DTO
{
    public abstract String getA();
}

with AutoGson defined as:

@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.TYPE)
public @interface AutoGson
{
    Class autoValueClass();
}

and a Gson type adapter defined as:

public class AutoValueTypeAdapterFactory implements TypeAdapterFactory
{
    @SuppressWarnings("unchecked")
    @Override
    public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> type)
    {
        Class<? super T> rawType = type.getRawType();

        AutoGson annotation = rawType.getAnnotation(AutoGson.class);
        if (annotation == null)
        {
            return null;
        }

        return (TypeAdapter<T>) gson.getAdapter(annotation.autoValueClass());
    }
}

which is used by Gson as:

Gson gson = new GsonBuilder().registerTypeAdapterFactory(new AutoValueTypeAdapterFactory())

this seems like adding too much complexity just to resolve sonar cube issue. — vatsal mevada, Oct 27 '17 at 09:58

Sonar showing issue for private fields of DTO class

2 Answers2