Why Exclusion Strategy by name does not prevent “class declares multiple JSON fields named XXX” error?

[Cahangirova Gunel]

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I have to serialize Java classes without modifying their source code. I am using GSON and getting "class Person declares multiple JSON fields named serialVersionUID", as the superclass of Person also has this field. So I want to to exclude fields named serialVersionUID during serialisation to avoid this error (it is ok for my purposes) adding the code below: GsonBuilder gsonBuilder = new GsonBuilder(); ExclusionStrategy excludePolicy = new ExclusionStrategy() { @Override public boolean shouldSkipField(FieldAttributes arg0) { return arg0.getName().contains("serialVersionUID"); } @Override public boolean shouldSkipClass(Class<?> arg0) { return false; } }; gsonBuilder.addSerializationExclusionStrategy(excludePolicy); gsonBuilder.excludeFieldsWithModifiers(java.lang.reflect.Modifier.TRANSIENT); Gson gson = gsonBuilder.create(); Writer writer; try { writer = new FileWriter("fileLoc"); gson.toJson(personList, writer); writer.close(); } catch (IOException e) { e.printStackTrace(); } However, I still get the error and cannot understand the reason beyond it. Here is the example class hierarchy: public class Person extends SuperPerson { private static final long serialVersionUID = 1L; } public class SuperPerson { private static final long serialVersionUID = 1L; }

[vypro...@gmail.com]

I know this question is very old but I had the same issue and I found a workaround and I want to share it: just make transient serialVersionUID fields.

This is not the way of solving it for any other field, but serialVersionUID is a kind of special field as explained in Javadoc for Serializable interface: https://docs.oracle.com/javase/7/docs/api/java/io/Serializable.html

I'm sure any other field should be serialized by a JsonAdapter.

[Inderjeet Singh]

Something is wrong in the way you have setup your Gson instance. 

serialVersionID is a static field, and Gson ignores them.

Please submit a PR to the Gson project with a JUnit test that reproduces the problem, and we can take a look.