Gson: How to exclude specific fields from Serialization without annotations

Question

I\'m trying to learn Gson and I\'m struggling with field exclusion. Here are my classes

public class Student {    
  private Long                id;
  privat         


        

Answer 1

I came up with a class factory to support this functionality. Pass in any combination of either fields or classes you want to exclude.

public class GsonFactory {

    public static Gson build(final List fieldExclusions, final List> classExclusions) {
        GsonBuilder b = new GsonBuilder();
        b.addSerializationExclusionStrategy(new ExclusionStrategy() {
            @Override
            public boolean shouldSkipField(FieldAttributes f) {
                return fieldExclusions == null ? false : fieldExclusions.contains(f.getName());
            }

            @Override
            public boolean shouldSkipClass(Class clazz) {
                return classExclusions == null ? false : classExclusions.contains(clazz);
            }
        });
        return b.create();

    }
}

To use, create two lists (each is optional), and create your GSON object:

static {
 List fieldExclusions = new ArrayList();
 fieldExclusions.add("id");
 fieldExclusions.add("provider");
 fieldExclusions.add("products");

 List> classExclusions = new ArrayList>();
 classExclusions.add(Product.class);
 GSON = GsonFactory.build(null, classExclusions);
}

private static final Gson GSON;

public String getSomeJson(){
    List list = getEntitiesFromDatabase();
    return GSON.toJson(list);
}