I have two tables in my database USERS and ADDRESSES, each user can have many addresses.
I have build entity classes with NetBeans wizard, and it create the classes well:
#Entity
#Table(name = "USERS")
#XmlRootElement
public class User implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Basic(optional = false)
#Column(name = "ID")
private Integer id;
// Some fields.......
#OneToMany(cascade = CascadeType.ALL, mappedBy = "user")
private Collection<Address> addressCollection;
public User() {
}
// Getters and Setters.......
}
#Entity
#Table(name = "ADDRESSES")
#XmlRootElement
public class Address implements Serializable {
private static final long serialVersionUID = 1L;
#EmbeddedId
protected AddressPK addressPK;
// Some fields.......
#JoinColumn(name = "USER_ID", referencedColumnName = "ID", insertable = false, updatable = false)
#ManyToOne(optional = false)
private User user;
public Address() {
}
// Getters and Setters.......
}
#Embeddable
public class AddressPK implements Serializable {
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Basic(optional = false)
#Column(name = "ID")
private int id;
#Basic(optional = false)
#NotNull
#Column(name = "USER_ID")
private int userId;
public AddressPK() {
}
}
In the session I save the User instance of the current logged in user. But the User's addressCollection never updates when I change the database like:
Address newAddr = new Address();
// Sets values to newAddr......
AddressFacade addrDao = new AddressFacade();
addrDao.create(newAddr); // Succeeded
LoginManager.getCurrentUser().getAddressCollection(); // Returns the old address list.
How can I refresh the current user's instance to get the correct addressCollection?
First, when you have a bidirectional relationship, JPA requires that you keep both sides of the relationship in synch with each other. This allows caching entities and other performance enhancements to be enabled by many providers. In this case, when you set the USER_ID field, you should update the User's addressCollection that is affected by the change so that your object model stays in synch with what you are committing to the database.
An alternative is to force a refresh manually on the User instance. This can be done with a em.refresh(user) call, or through provider specific options and query hints. This is usually the least performant option though as it requires a database hit that isn't needed.
Related
I have already a user model.
Now I have created a movie model, my requirement is that whenever any existing user is going to add any movie, at that time user_id and movie_id will be store in the movie_added_by table.
Here user model needs to map one to many to movie_added_by and similarly, the movie will be mapped to movie_added_by.
For better understanding, you can refer to the DB diagram.
I really don't know how can I do by using hibernate annotation
The user model is like this:
#Getter
#Setter
public class User {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "user_id", unique = true, nullable = false)
private Integer user_id;
private String name;
}
The movie model is like this:
#Getter
#Setter
public class Movie implements Serializable
{
private static final long serialVersionUID = -6790693372846798580L;
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "movie_id", unique = true, nullable = false)
private Integer movie_id;
private String movie_name;
}
You probably want to create a #ManyToMany relationship between the entities. There are 2 ways of doing it (with intermediary table created explicitly or by Hibernate.
In simple approach your entities would look as following:
public class User {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "user_id", unique = true, nullable = false)
private Integer user_id;
private String name;
#ManyToMany(cascade = CascadeType.Persist)
#JoinTable(name="user_movie",
joinColumns = {#JoinColumn(name="user_id")},
inverseJoinColumns = {#JoinColumn(name="movie_id)})
private Set<Movie> movies = new HashSet<>();
}
public class Movie implements Serializable
{
private static final long serialVersionUID = -6790693372846798580L;
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "movie_id", unique = true, nullable = false)
private Integer movie_id;
private String movie_name;
#ManyToMany(cascade = CascadeType.Persist, mappedBy = "movies" //field from the user class responsible for mapping)
private Set<User> users = new HashSet<>()
}
So basically here you tell Hibernate to create an intermediary table and keep there correlated id's of those 2 entities. Couple of other notes here:
a) you might want to change the id variable type from Integer to Long in case your entities grow;
b) If you have annotated a column with #Id, you don't have to use unique=true and nullable = false in the column annotation;
c) remember about implementing no-args constructor;
d) remember to exclude relationship fileds from the equals(), hashCode() and the toString() methods;
There is another way, where you explicitly create a model for the table keeping relationships. This might become handy, when it turns out that You need to keep more data in the 'relationship table'. In that case, Your entities would look as following:
public class User {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "user_id", unique = true, nullable = false)
private Integer user_id;
private String name;
#OnetToMany(cascade = CascadeType.PERSIST, mappedBy = "user")
private Set<AddedMovie> addedMovies = new HashSet<>()
}
public class Movie implements Serializable
{
private static final long serialVersionUID = -6790693372846798580L;
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "movie_id", unique = true, nullable = false)
private Integer movie_id;
private String movie_name;
#OneToMany(cascade = CascadeType.PERSIST, mappedBy = "movie")
private Set<AddedMovie> moviesAddedByUser = new HashSet<>();
}
#Data
#AllArgsConstructor
#NoArgsConstructor
#Builder
#Entity
public class AddedMovie{
#Id
#GeneratedValue
private Long id;
#ManyToOne(cascade = CascadeType.PERSIST)
#JoinColumn(name = "user_id")
private User user;
#ManyToOne(cascade = CascadeType.PERSIST)
#JoinColumn(name = "movie_id")
private Movie movie;
// sine this entity has now its own lifecycle, you can add more fields here
private Integer rating;
private LocalDateTime movieAddedOn;
}
I have a User Class
#Entity(name = "users")
#Table(name = "users")
public class User implements UserDetails {
static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "user_id", nullable = false)
private Long id;
#Column(name = "username", nullable = false, unique = true)
private String username;
#Column(name = "password", nullable = false)
private String password;
}
Tied to a simple Repository
public interface UserRepository extends PagingAndSortingRepository<User, Long> {
}
And I have an Instructor Class that has a nested User object
#Entity
#Table(name = "instructors")
public class Instructor {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "instructor_id", nullable = false, updatable = false)
private Long id;
#OneToOne(fetch = FetchType.EAGER)
#JoinColumn(name = "user_id")
private User user;
#OneToMany(fetch = FetchType.EAGER)
#JoinColumn(name = "course_id")
private List<Course> courses;
}
It is saved with the following repository
public interface InstructorRepository extends PagingAndSortingRepository<Instructor, Long> {
}
The JSON I am posting
{
"user": {
"id": 1
}
}
When I try to do a POST to /instructors . User is coming in null. Is there something I am missing to get JPA to tie the two together? I have tried adding CascadeType.ALL onto the field and that only throws a detached persist exception.
Leave the CascadeType.ALL to Instructor like you already tried:
#ManyToOne(fetch = FetchType.EAGER, cascade=CascadeType.ALL)
#JoinColumn(name = "user_id")
private User user;
In addition add the following to User. Seems to work with me. It provides the mapping information and makes JPA treat User managed
#OneToMany(mappedBy="user")//, cascade=CascadeType.ALL)
private List<Instructor> instructors = new ArrayList<>();
I have commented out the cascadeType in the above but it might be useful if you want to persist User wit all of its Instructors.
public class Customer implements Serializable {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "idCustomer")
private Integer idCustomer;
#OneToMany(cascade = CascadeType.ALL, mappedBy = "idCustomer")
private Collection<Login> loginCollection;
}
public class Login implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Basic(optional = false)
#Column(name = "idLogin")
#JoinColumn(name = "idCustomer", referencedColumnName = "idCustomer")
#ManyToOne(optional = false)
private Customer idCustomer;
}
//trying to save the customer and login in the database
ArrayList<Login> logins = new ArrayList<Login>();
Login log = new Login();
log.setIdCustomer(cust);
logins.add(log);
cust.setLoginCollection(logins);
cust = custRepo.save(cust); //failed
//Login log = new Login();
//log.setUName(user);
//log.setPassword(pass);
//log.setIdCustomer(cust);
//cust = custRepo.save(cust);
//logRepository.save(log); //failed too.
I'm using spring data in my project. I have 2 model classes Customer and Login. My login class has a foreign key idCustomer in the database. When I try to save the customer without a login, it works fine but the problem is that I can't save a login object in the database.
I'm getting an error saying
Unknown column 'id_customer' in 'field list'
the jpa entities are generated.
Here is an image actual database.
Too many idCustomers in your example.
Try the code below.
I have changed a bit the annotated members #OneToMany and #ManyToOne,
following the tips established here JPA JoinColumn vs mappedBy
Also I have included idLogin in Login class. I don't know if this was a typo in your code.
public class Customer implements Serializable {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "idCustomer")
private Integer idCustomer;
#OneToMany(cascade = CascadeType.ALL, mappedBy = "customer")
private Collection<Login> loginCollection;
}
public class Login implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Basic(optional = false)
#Column(name = "idLogin")
private Integer idLogin;
#ManyToOne
#JoinColumn(name="idCustomer", insertable=false, updatable=false)
private Customer customer;
}
You need to you annotation
#JoinColumn
please go through these
https://docs.jboss.org/hibernate/jpa/2.1/api/javax/persistence/JoinColumns.html
http://docs.oracle.com/javaee/6/api/javax/persistence/JoinColumn.html
I have the following tables :
#Entity
#Table(name = "CUSTOMER")
public class Customers implements Serializable {
private static final long serialVersionUID = -5419345600310440297L;
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "cust")
#SequenceGenerator(name = "cust", sequenceName = "cust_ID_SEQ")
#Column(name = "CUSTOMER_ID")
private Long id;
#Column(name = "NAME")
private String name;
#OneToMany(mappedBy = "customer", cascade = CascadeType.PERSIST)
private Set<CustomerDeal> customerDeals;
//getters and setters goes here ....
}
#Entity
#Table(name = "DEALS")
public class Deals implements Serializable {
private static final long serialVersionUID = -7197428343863081750L;
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "deals_seq")
#SequenceGenerator(name = "deals_seq", sequenceName = "DEALS_SEQ")
#Column(name = "DEAL_ID")
private Long dealId;
#Column(name = "DEAL_NAME")
private String dealColName;
//getters setters
}
#Entity
#Table(name = "CUSTOMER_DEALS")
public class CustomerDeals implements Serializable {
private static final long serialVersionUID = -4249326793843278525L;
#EmbeddedId
private CustomerDealId customerDealId;
#ManyToOne(fetch = FetchType.EAGER)
#JoinColumn(name = "CUSTOMER_ID", insertable = false, updatable = false)
private Customers customers;
#ManyToOne(fetch = FetchType.EAGER)
#JoinColumn(name = "DEAL_ID", insertable = false, updatable = false)
private Deals deals;
//getters setters
}
#Embeddable
public class CustomerDealId implements Serializable {
private static final long serialVersionUID = 9086627167426987610L;
#Column(name = "DEAL_ID")
private Long dealId;
#Column(name = "CUSTOMER_ID")
private Long customerId;
}
however when I try to create a new customer
Customer cust - new Customer ()
cust.setName("Foo")
CustomerDeals custDeals = new CustomerDeals()
Set<CustomerDeal> custDealsSet = new HashSet<CustomerDeal>
CustomerDeal custDealsSet1 = new CustomerDeal()
CustomerDeal custDealsSet2 = new CustomerDeal()
custDealsSet1.setDeals(dealsRepository.findOne(1))//getting existing deal
custDealsSet1.customers(cust)
custDealsSet2.setDeals(dealsRepository.findOne(2))//getting existing deal
custDealsSet2.customers(cust)
custDealsSet.add(custDealsSet1)
custDealsSet.add(custDealsSet2)
cust.setCustomerDeals(custDealsSet)
customerRepository.saveAndFlush(cust)
customerRepository.saveAndFlush(cust)
I am getting
org.hibernate.id.IdentifierGenerationException: null id generated
for:class CustomerDeal
This is not duplication of this question
Your code that throws exception does not make sense so I guess it is not real code.
CustomerDeal has composite key, so you would not be able to retrieve it with dealsRepository.findOne(1), which means that you probably were retrieveing Deal not CustomerDeal but then the part would never compile:
Set<CustomerDeal> custDealsSet = new HashSet<CustomerDeal>();
custDealsSet.add(dealsRepository.findOne(1))
So, apart from that, I guess you were retrieving the existing deals. And you made a new customer. As the key of CustomerDeal depeneds on both customer and deal, both custumer and deal have to be set before persisting it which you probably forgot to do (and you got your exception). So it should look like:
Customer cust - new Customer ();
cust.setName("Foo");
CustomerDeals custDeal = new CustomerDeals();
custDeal.setCustomer(cust);
custDeal.setDeal(dealsRepository.findOne(1));
cust.getCustomerDeals().add(custDeal);
custDeal = new CustomerDeals();
custDeal.setCustomer(cust);
custDeal.setDeal(dealsRepository.findOne(2));
cust.getCustomerDeals().add(custDeal);
customerRepository.saveAndFlush(cust);
Now you are probably still in trouble. If you override the equals and hash on CustomerDeal so they are ID based (which typical code generator for entities does), both new CustomerDeals instances have them as null, so when you add them to the set the second one will override the first inserted (as null ids will be equals).
You also need to inform JPA that the ID will come from the relations.
In your CustomerDea you need to add #MapsId annotation (on both joins), like:
#MapsId("customerId")
#ManyToOne(fetch = FetchType.EAGER)
#JoinColumn(name = "CUSTOMER_ID", insertable = false, updatable = false)
private Customers customers;
Finally, unless your CustomerDeal table contains additional apart from CUSTOMER_ID and Deal_ID, then, it is a simple joint table and should not be mapped at all. That way you will save yourself a lot of trouble.
The reason why you got the error mentioned above is due to a mapping issue(I cant figure out what exactly is wrong though). As a completely different approach, I have modified your mappings. I have tested this and it is working fine. The advantage for you with this mapping is that it makes the CustomerDeals class redundant. Please note that I have removed the sequences as I am using MySQL.
#Entity
#Table(name = "CUSTOMERS")
public class Customer implements Serializable {
private static final long serialVersionUID = -5419345600310440297L;
#Id #GeneratedValue(strategy=GenerationType.IDENTITY)
#Column(name = "CUSTOMER_ID")
private Long id;
#Column(name = "NAME")
private String name;
#ManyToMany(cascade = {CascadeType.ALL}, fetch = FetchType.EAGER)
#JoinTable(
name="CUSTOMER_DEALS",
joinColumns = #JoinColumn( name="CUSTOMER_ID"),
inverseJoinColumns = #JoinColumn( name="DEAL_ID")
)
private Set<Deals> deals = new HashSet<Deals>();
//Setters and Getters to follow
}
The Deals Class will be
#Entity
#Table(name = "DEALS")
public class Deals implements Serializable {
private static final long serialVersionUID = -7197428343863081750L;
#Id #GeneratedValue(strategy=GenerationType.IDENTITY)
#Column(name = "DEAL_ID")
private Long dealId;
#Column(name = "DEAL_NAME")
private String dealColName;
#ManyToMany(fetch = FetchType.EAGER, mappedBy = "deals")
private Set<Customer> customers = new HashSet<Customer>(0);
//Setters and Getters here
}
Finally the main method which does the insert.
Customer customer = new Customer();
customer.setName("NewCust2");
Deals deals = new Deals();
deals.setDealColName("Deal2");
customer.getDeals().add(deals);
customerRepository.save(customer);
I have three entities User, Center and Profile, so a user has different profiles depending on the center he's in. So we have a table which links the three entities called *user_center_profile*.
Then we have another entity, called Permission which is linked to Profile, so a profile has several permissions.
Because the main entity is User, I have it maped like this:
#Entity
#Table(name = "profile")
public class Profile implements Serializable {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "idprofile")
private Long idProfile;
#Column(name = "codprofile")
private String codProfile;
#Column(name = "desprofile")
private String desProfile;
#OneToMany
#JoinTable(name = "profile_permission", joinColumns = { #JoinColumn(name = "idProfile") }, inverseJoinColumns = { #JoinColumn(name = "idPermission") })
private List<Permission> permissions = new ArrayList<Permission>();
/* getters and setters */
}
#Entity
#IdClass(CenterProfileId.class)
#Table(name = "user_center_profile")
public class CenterProfile implements Serializable {
#Id
#ManyToOne
private Center center;
#Id
#ManyToOne
private Profile profile;
/* getters and setters */
}
#Embeddable
public class CenterProfileId implements Serializable {
private static final long serialVersionUID = 1L;
#ManyToOne
#JoinColumn(name = "idCenter")
private Center center;
#ManyToOne
#JoinColumn(name = "idProfile")
private Profile profile;
/* getters, setters, equals, hashcode */
}
#Entity
#Table(name = "user")
public class User implements Serializable {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "idUser")
private Long idUser;
#Column(name = "codUser")
private String codUser;
/* other properties */
#ManyToMany(fetch = FetchType.EAGER)
#JoinTable(name = "user_center_profile", joinColumns = { #JoinColumn(name = "idUser") }, inverseJoinColumns = {
#JoinColumn(name = "idCenter"), #JoinColumn(name = "idProfile") })
private List<CenterProfile> centersProfileUser = new ArrayList<CenterProfile>();
#Transient
private Center selectedCenter;
/* getters, setters */
}
The thing is that at certain point I have to collect all the permissions that a certain user has... I tried several things and I got lazy load errors, no session or session closed errors, problem loading simultaneous bags...
I even tried to write a plain SQL query and I got the same error...
I can't see the way to build a DetachedCriteria for this, and I don't know if it will give an exception too..
My app can connect to different "centers", when he logs in he can choose which center he wants to connect to, but also once logged in, he can change centers... So when he changes it, I have to recalculate his permissions... that's why I need to get that list of permissions..
How could I get this done in a proper way?
In the end, I built the query like this:
HashSet<Permission> set = new HashSet<Permission>();
for (CenterProfile cp : usuario.getCentersProfileUsuario()) {
// First we build subcriteria to return all the permissions for a certain profile
DetachedCriteria criteriaProfile = DetachedCriteria
.forClass(Profile.class);
criteriaProfile.add(Restrictions.eq("idProfile", cp.getProfile()
.getIdProfile()));
criteriaProfile.createAlias("permissions", "permission");
criteriaProfile.setProjection(Property.forName("permission.idPermission"));
// Then we build criteria for permissions, which should match the results given by subcriteria
DetachedCriteria criteria = DetachedCriteria
.forClass(Permission.class);
criteria.add(Property.forName("idPermission").in(criteriaProfile));
List<Permission> permissions = getHibernateTemplate().findByCriteria(
criteria);
set.addAll(permissions);
}