HttpMessageConverter for Single Object and List of Object

I have an Object (here: Property) and I want to add csv export ability to my Spring Backend for single and list of objects.

I added this to my config:

@Override
public void configureContentNegotiation(ContentNegotiationConfigurer configurer) {
    configurer.(more config).mediaType("csv", new MediaType("text", "csv"));
}

@Override
public void extendMessageConverters(List<HttpMessageConverter<?>> converters) {
     converters.add(new PropertyConverter());
     converters.add(new StatsConverter());
}

and the Property Converter looks like this:

public class PropertyConverter extends AbstractGenericHttpMessageConverter<Property> {

    private static final Logger LOGGER = LoggerFactory.getLogger(PropertyConverter.class);

    public PropertyConverter() {
        super(new MediaType("text", "csv"));
    }

    @Override
    protected void writeInternal(Property property, Type type, HttpOutputMessage outputMessage) throws IOException, HttpMessageNotWritableException {
        try (var writer = new OutputStreamWriter(outputMessage.getBody())) {
            new StatefulBeanToCsvBuilder<>(writer).withSeparator(',').build().write(property);
        } catch (CsvDataTypeMismatchException | CsvRequiredFieldEmptyException ex) {
            LOGGER.error("CSV failed to convert property: ".concat(property.getExternalId()).concat(", exception: ".concat(ex.toString())));
        }
    }

    @Override
    protected Property readInternal(Class<? extends Property> clazz, HttpInputMessage inputMessage) throws IOException, HttpMessageNotReadableException {
        return null;
    }

    @Override
    public Property read(Type type, Class<?> contextClass, HttpInputMessage inputMessage) throws IOException, HttpMessageNotReadableException {
        return null;
    }
}

This code works for a Single Property. When I try to return a list of Properties:

org.springframework.web.util.NestedServletException: Request processing failed; nested exception is java.lang.ClassCastException: class java.util.LinkedHashMap cannot be cast to class eu.webeng.model.Property (java.util.LinkedHashMap is in module java.base of loader 'bootstrap'; eu.webeng.model.Property is in unnamed module of loader 'app')
    ...

Caused by: java.lang.ClassCastException: class java.util.LinkedHashMap cannot be cast to class eu.webeng.model.Property (java.util.LinkedHashMap is in module java.base of loader 'bootstrap'; eu.webeng.model.Property is in unnamed module of loader 'app')
    at eu.webeng.converter.PropertyConverter.writeInternal(PropertyConverter.java:20) ~[classes/:na]
    at org.springframework.http.converter.AbstractGenericHttpMessageConverter.write(AbstractGenericHttpMessageConverter.java:104) ~[spring-web-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.AbstractMessageConverterMethodProcessor.writeWithMessageConverters(AbstractMessageConverterMethodProcessor.java:287) ~[spring-webmvc-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.HttpEntityMethodProcessor.handleReturnValue(HttpEntityMethodProcessor.java:219) ~[spring-webmvc-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.web.method.support.HandlerMethodReturnValueHandlerComposite.handleReturnValue(HandlerMethodReturnValueHandlerComposite.java:82) ~[spring-web-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    ....

I tried to add a PropertyListConverter but then it doesn't work for Single Property. When I tried to add both, the first converter added is being used.

How can I make the Converter work for Single and List of Property (or any Object)

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