QueryDsl BooleanExpression - nested field is NULL - spring-boot

Question

I want to create a predicate with QueryDSL and I don't know why but some nested field is NULL:
BooleanExpression emailSender = qFreight.message.account.user.id.eq(userId);
user is NULL.
qFreight.message.account.user gives me NPE error
And then in logs I have
.180 ERROR 7316 --- [nio-9090-exec-3] p.a.m.s.filter.JwtAuthorizationFilter : Request processing failed; nested exception is java.lang.NullPointerException
Of course I have generated QFreight, QMessage, QAccount, QUser... Where can bet the problem? I don't have any idea
UPDATE
My entities (the question is how to set #QueryInit properly):
#Entity
#Table(name = "freight")
#Getter
#Setter
#Builder
#NoArgsConstructor
#AllArgsConstructor
public class Freight {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(nullable = false, updatable = false)
private Long id;
#QueryInit("*")
#ManyToOne(fetch = FetchType.EAGER)
#JoinColumn(name = "message_id")
private Message message;
#OneToOne(fetch = FetchType.LAZY)
#JoinColumn(name = "user_id")
private User user;
}
#Entity
#Table(name="message")
#Getter
#Setter
public class Message {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(nullable = false, updatable = false)
private Long id;
#ManyToOne(fetch = FetchType.LAZY)
#JoinColumn(name = "email_account_id", foreignKey = #ForeignKey(name = "FK_account_to_message"))
private Account account;
}
#Entity
#Table(name="account")
#Getter
#Setter
#NoArgsConstructor
#SuperBuilder(builderMethodName = "of")
public class Account {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(nullable = false, updatable = false)
private Long id;
#ManyToOne(fetch = FetchType.LAZY)
private User user;
}

Answer 1

qFreight.message.account.user.id is not a valid JPQL expression. You'd have to create the joins between the entities explicitly: JOIN qFreight.message message JOIN message.account account JOIN account.user user. In QueryDSL this would be: .join(qFreight.message, QMessage.message).join(QMessage.message.account, QAccount.account).join(QAccount.account.user, QUser.user).where(QUser.user.id.eq(...)).
Furthermore, the QueryDSL metamodel by default is only initialized one level deep. This is a performance decision. If you need the metamodel to be initialized deeper (even though usecases are rare, because JPQL lacks support for implicit joins), you have to use #QueryInits: http://www.querydsl.com/static/querydsl/4.4.0/reference/html_single/#d0e2265