How to use Mongo with Spring Data without ObjectId

Question

I have an existing mongo database in which ids (_id) are persisted as plain Strings.. This is sample data in Mongo DB:

{
    \"_id\" : \"528bb0e2e4b0442f1479         


        

Answer 1

A workaround that could work is to create your own converter for ObjectId.

You can customize the mongo mapper by supplying a @Bean of type MappingMongoConverter

@Configuration
public class MongoConfig {

    @Bean
    public CustomConversions customConversions() {
        List> converters = new ArrayList>();
        converters.add(new MyObjectIdConverter());
        return new CustomConversions(converters);
    }

    @Bean
    public MappingMongoConverter mappingMongoConverter(MongoDbFactory factory, MongoMappingContext context, BeanFactory beanFactory) {
        DbRefResolver dbRefResolver = new DefaultDbRefResolver(factory);
        MappingMongoConverter mappingConverter = new MappingMongoConverter(dbRefResolver, context);
        try {
            mappingConverter.setCustomConversions(customConversions());
        }
        catch (NoSuchBeanDefinitionException ignore) {}

        // Don't save _class to mongo
        mappingConverter.setTypeMapper(new DefaultMongoTypeMapper(null));

        return mappingConverter;
    }

}