NullConverter for Debezium sample

NullConverter.java

public class NullConverter implements CustomConverter<SchemaBuilder, RelationalColumn> {
	
	private SchemaBuilder stringSchema;

	public void configure(Properties props) {
		stringSchema = SchemaBuilder.string();	}

	public void converterFor(RelationalColumn column, ConverterRegistration<SchemaBuilder> registration) {
		Converter converter = this::anyToString;
		registration.register(stringSchema, converter);
	}

	private String anyToString(Object rawValue) {
		String converted;
		if (rawValue == null) {
			converted = "[null]";
		} else {
			converted = rawValue.toString();
		}

		return converted;
	}
}