Enums cannot be serialized without transforming them.

I propose, that all java enums are serialized (and deserialized) using the name() method (or valueOf() method).

Example (using QueryDSL):

@Entity
public enum Type {
TYPE1, TYPE2
}

public class MyObject {

protected Type type;

public Type getType() {
}

public void setType(Type type)

}

Usage:

QMyObject.myObject.type.eq(Type.TYPE1); // ends in:

java.lang.IllegalArgumentException: can't serialize class Type
at org.bson.BSONEncoder._putObjectField(BSONEncoder.java:213)
at org.bson.BSONEncoder.putObject(BSONEncoder.java:123)
at org.bson.BSONEncoder._putObjectField(BSONEncoder.java:173)
at org.bson.BSONEncoder.putObject(BSONEncoder.java:123)
at org.bson.BSONEncoder.putObject(BSONEncoder.java:69)
at com.mongodb.OutMessage.putObject(OutMessage.java:189)
at com.mongodb.OutMessage._appendQuery(OutMessage.java:62)
at com.mongodb.OutMessage.query(OutMessage.java:39)
at com.mongodb.DBApiLayer$MyCollection.__find(DBApiLayer.java:293)
at com.mongodb.DB.command(DB.java:152)
at com.mongodb.DBCollection.getCount(DBCollection.java:760)
at com.mongodb.DBCollection.getCount(DBCollection.java:731)
at com.mongodb.DBCollection.count(DBCollection.java:697)
at com.mysema.query.mongodb.MongodbQuery.count(MongodbQuery.java:184)
at org.springframework.data.document.mongodb.repository.QueryDslMongoRepository.count(QueryDslMongoRepository.java:151)
at sun.reflect.GeneratedMethodAccessor9.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:616)
at org.springframework.data.repository.support.RepositoryFactorySupport$QueryExecuterMethodInterceptor.executeMethodOn(RepositoryFactorySupport.java:356)
at org.springframework.data.repository.support.RepositoryFactorySupport$QueryExecuterMethodInterceptor.invoke(RepositoryFactorySupport.java:337)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202)
at $Proxy18.count(Unknown Source)