无法使用休眠从多个映射表中获取数据

Question

Hi i am new to hibernate.

I have a java web project and i am using spring mvc with hibernate in this project and for database i am using my sql.

The issue i am facing is that : i have a table in db as user and in java project as user.java and i have 2 other tables references and messgaes.In java project i have referances.java and Messages.java and i have created the mapping tables as user_referances_mapping(user_id, referance_id) and user_messages_mapping(user_id, reference_id).

and i have one to many relationship between user and referances table and user and messages table.

I want to get data from both references and messgaes table when i am getting user data.

when i am using "FROM User u LEFT JOIN FETCH u.referances WHERE u.contactNo=:contactNo or u.email=:email" i get reference table data.

So can anyone help me getting the solution, that how i can get the data of the referances table and messages table at the same time and what should be the solution to it.

mapping of referances table and messgaes table in user table:

@OneToMany
@Basic(optional = true)
@BatchSize(size = 5)
@Cascade(CascadeType.ALL)
@Cache(region = IAppConstants.CACHE_REFERANCES, usage = CacheConcurrencyStrategy.READ_WRITE)
@JoinTable(name = "user_referances_mapping", joinColumns = { @JoinColumn(name = "user_id") }, inverseJoinColumns = { @JoinColumn(name = "referance_id") })
private List<Referances> referances = new ArrayList<Referances>();

@OneToMany
@Basic(optional = true)
@BatchSize(size = 5)
@Cascade(CascadeType.ALL)
@Cache(region = IAppConstants.CACHE_MESSAGES, usage = CacheConcurrencyStrategy.READ_WRITE)
@JoinTable(name = "user_messages_mapping", joinColumns = { @JoinColumn(name = "user_id") }, inverseJoinColumns = { @JoinColumn(name = "message_id") })
private List<Messages> messages = new ArrayList<Messages>();

UserDao class function :

public User getC2SUserByContactNoOrEmail(final String value) throws ApplicationException {
try{
@SuppressWarnings("unchecked")
Query query = currentSession().createQuery(
        IQueryConstants.FETCH_USER_BY_CONTACTNO_OR_EMAIL);
query.setParameter("contactNo", value);
query.setParameter("email", value);
return (User) query.uniqueResult();
}catch(Exception e){
    throw new ApplicationException(
            "Issue occurred while fetching user by: " + value, e);
}
//return null;

}

Answer 1

Use @LazyCollection(LazyCollectionOption.FALSE)

with the relationship entry in the User class for messages.