Really appreciate ANY help (at least ways how to trace root cause of the problem) because I've been fighting with this for several days and didn't find even workaround.
The problem itself: I have a few entities, all of them work good - persist(), find() etc. except one method where I create two different entities (Order and Items, one order can have many Items). After calling em.persist(..) order is saved and I see its id generated by DB, item is saved to DB (I see it through SELECT directly in DB) but it shows ID=0. And whatever I do it always 0 (e.g. when I open the order I still see its ID=0) until I restart server - then it shows correct ID of item.
Code of the method (after logging I added actual values I get):
public void createOrderFromItems(ArrayList<TehnomirItemDTO> items, User user) {
Order ord = new Order();
User managers = getUserByEmail(Constants.ALL_MANAGERS_GROUP);
ord.setAssignedTo(managers);
Date date = new Date();
ord.setCreatedOn(date);
User customer = user;
ord.setCustomer(customer);
BigDecimal custBalance = new BigDecimal(0);
ArrayList<Balance> balances = getBalanceForUser(customer);
for (Balance b:balances) {
custBalance.add(b.getAmount());
}
logger.debug("before1. order: "+ord.getOrderId()); //here I get 0
em.persist(ord);
logger.debug("before2. order: "+ord.getOrderId()); //still 0
State new_state = getStateByName(SharedConstants.STATE_NEW);
logger.debug("before3. order: "+ord.getOrderId()); //here I get actual ID, generated by DB, e.g. 189
State overpriced = getStateByName(SharedConstants.STATE_LIMIT_EXCEEDED);
ArrayList<Item> itemList = new ArrayList<Item>();
for (TehnomirItemDTO tid:items) {
Item item = new Item(tid);
item.setOrder(ord);
logger.debug("order inside2:"+ord.getOrderId()); //again, actual ID
item.setPriceInt(tid.getPrice_int());
custBalance = custBalance.subtract(item.getPriceInt());
if (custBalance.floatValue()>0) {
item.setStateBean(new_state);
} else item.setStateBean(overpriced);
logger.debug("item before:"+item.getItemId()); //here I get 0
em.persist(item);
item = em.merge(item);
em.setFlushMode(FlushModeType.COMMIT);//added just in case it would work but it didn't
em.flush();//same as previous line
Item tst = getItemByID(1);
logger.debug("item after:"+item.getItemId()+" ord:"+ord.getOrderId()); //again, orderID is correct, itemID is 0
itemList.add(item);
}
ord.setItems(itemList);
State new_state2 = getStateByName(SharedConstants.STATE_NEW);
logger.debug(ord.getItems().get(0).getItemId()+" order: "+ord.getOrderId());//again, orderID is correct, itemID is 0
}
Order class:
#Entity
#Table(name="orders")
public class Order implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy=GenerationType.IDENTITY/*, generator="ORDERS_ORDERID_GENERATOR"*/)
#Column(name="ORDER_ID")
private int orderId;
#Temporal(TemporalType.TIMESTAMP)
#Column(name="CREATED_ON")
private Date createdOn;
//bi-directional many-to-one association to Item
#OneToMany(mappedBy="order")
private List<Item> items;
//uni-directional many-to-one association to User
#ManyToOne
#JoinColumn(name="ASSIGNED_TO")
private User assignedTo;
//uni-directional many-to-one association to User
#ManyToOne
#JoinColumn(name="CUSTOMER")
private User customer;
public Order() {
}
public int getOrderId() {
return this.orderId;
}
}
Item class (removed getters and setters to make it more readable):
#Entity
#Table(name="items")
public class Item implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#Column(name="ITEM_ID")
private int itemId;
private String code;
private BigDecimal weight;
public BigDecimal getWeight() {
return weight;
}
public void setWeight(BigDecimal weight) {
this.weight = weight;
}
private String comments;//any additional info user'd like to add
private String description;
#Column(name="EXT_ID")
private int extId;
private String manufacturer;
#Column(name="PRICE_EXT")
private BigDecimal priceExt;
#Column(name="PRICE_INT")
private BigDecimal priceInt;
private String region;
private String term;
//bi-directional many-to-one association to Order
#ManyToOne(cascade=CascadeType.PERSIST)
#JoinColumn(name="ORDER_ID")
private Order order;
//bi-directional many-to-one association to State
#ManyToOne
#JoinColumn(name="STATE")
private State state;
}
I had some thoughts about caching so I added to my persistence.xml lines
property name="toplink.cache.type.default" value="NONE"
property name="toplink.cache.type.Order" value="NONE"
but it didn't help either
Try to change int to Integer
private Integer orderId;
and getters and setters as well.
You mention Item is assigned an ID value by the database, but missed the #GeneratedValue(strategy=GenerationType.IDENTITY) annotation you have on order. This is what tells JPA the db controls the value, otherwise it expects the application to set it, keeping it the default 0.
after calling em.persist(obj), call em.flush();. It should work.
better have a private method save
like
private void save(object obj)
{
em.persist(obj);
em.flush();
}
Related
Hello programming council, this is my first use of JPA in anger.
I have 2 Tables:
Entity
#Table(name="category")
public class Category {
#Id
#Column(name="id")
#GeneratedValue(strategy=GenerationType.IDENTITY)
private int id;
#Column(name="category")
private String category;
#Column(name="budget")
private double budget;
#Column(name="savings")
private String savings;
#Column(name="archive")
private String archive;
Entity
#Table(name="Transaction")
public class Transaction {
#Id
#Column(name="transaction_no")
#GeneratedValue(strategy=GenerationType.IDENTITY)
private long transactionNo;
#Column(name="transaction_date")
private String transactionDate;
#Column(name="transaction_category")
private String transactionCategory;
#Column(name="transaction_description")
private String transactionDescription;
#Column(name="transaction_amount")
private double transcationAmount;
#Column(name="transaction_auto")
private String transactionAuto;
I want to create a new object called Tile which will contain String category and String balance, the SQL for which would be:
select t.transaction_category as category, sum(t.transaction_amount) as balance
from budgeteer.category c
join budgeteer.transaction t
on c.category = t.transaction_category
group by t.transaction_category;
What is the easiest/best way for me to accomplish this?
Thanks in advance.
Ok, so after a little more research, I discovered that I could actually just do this with the same Entity, repository and service without generating a table. You just need to leave out the #Table annotation when you create your entity.
I use h2 in memory db and I don't want to create duplicate locations in my DataBase. Only when I use createItem and input location column id manualy it write it to the same location. Otherwise even if the country city gps coordinates are the same app write it to other location with it's id.
I tried to understand but It's not working
I got these entities.
#Entity
#Table(name = "item_System_items")
public class Item {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Integer id;
private String title;
private String description;
private BigDecimal price;
private Integer stock;
#ManyToOne
#JoinColumn(name = "location_id")
#Cascade(value={org.hibernate.annotations.CascadeType.ALL})
private Location location;
And
#Entity
#Table(name = "item_System_locations")
public class Location {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private Integer id;
private String country;
private String city;
private String street;
private String gpsCoordinates;
SETTERS AND GETTERS IS THERE I JUST NOT POST THEM HERE
Controller
#RestController
#RequestMapping("/items")
public class ItemsController {
#Autowired
private ItemsService service;
#PostMapping
#ResponseStatus(value=HttpStatus.CREATED)
public int createItem(#RequestBody Item item) {
return service.createItem(item);
}
Service
#Service
#Transactional
public class ItemsService {
#Autowired
private ItemJPARepository repository;
public int createItem(Item item) {
return repository.save(item).getId();
}
I expect after re-coding app doesn't make new location if the column values are the same.
Thank you people!
If you really help me I would be so happy!
There is nothing in your Entity definitions to tell the ORM about the constraint you want.
You can add #UniqueConstraint to the #Table in your Location entity and specify which column(s) must all be in a unique combination (example given in the linked documentation):
#Table(
name="EMPLOYEE",
uniqueConstraints=
#UniqueConstraint(columnNames={"EMP_ID", "EMP_NAME"})
)
This will add a check in the database, if the ORM is managing your database schema, which will throw an exception when violated.
I am trying to establish the aggregation relationship between two Java classes through JPA annotations in order to persist them into a database.
public class Ticket
{
private String ticketNo;
private Date releasedDate;
private boolean printed;
}
public class Discount
{
private String percentage;
private Date releasedDate;
private boolean printed;
}
Such as mentioned here, the aggregation relationship is unidirectional and thus, only it is necessary to map one side. From the solution given by this page, I think the solution will be:
public class Discount
{
private String percentage;
private Date releasedDate;
private boolean printed;
#ManyToOne(name="TICKET_ID")
private Ticket ticket;
}
However, in some examples of aggregation, the many side class appears inside the one side class. Thus, I am considering this too:
public class Ticket
{
private String ticketNo;
private Date releasedDate;
private boolean printed;
#OneToMany(mappedBy="ticket")
private List<Discount> discounts = new ArrayList<Discount>();
}
Which option is the proper one?
This how you map a unidirectional many-to-one relationship:
#Entity
public class Ticket {
#Id
#GeneratedValue
private Long id;
private String ticketNo;
private Date releasedDate;
private boolean printed;
// getters and setters
}
#Entity
public class Discount {
#Id
#GeneratedValue
private Long id;
private String percentage;
private Date releasedDate;
private boolean printed;
#ManyToOne(cascade = {CascadeType.PERSIST, CascadeType.MERGE})
#JoinColumn(name = "TICKET_ID") // you can rename the join column
private Ticket ticket;
// getters and setters
}
Note:
JoinColumn (foreign key in the database terminology) must be on the many side of the relationship (this is the Discount in your case).
The #Id annotations are also mandatory. In this case, the ID will be generated by the persistence provider automatically. If you are using database sequence or table or some other strategy you can redefine it.
That looks right to me. A discount has a ticket. You could also include the discounts accessible from the tickets like ticket.getDiscounts() if you need to access them in a query such as SELECT t FROM Ticket t WHERE t.discounts.percentage >= :discountPercentage.
#Entity
public class Ticket {
#Id
private String ticketNo;
private Date releasedDate;
private boolean printed;
#OneToMany(mappedBy = "ticket", fetch = FetchType.LAZY)
private List<Discounts> discounts;
}
#Entity
public class Discount {
private String percentage;
private Date releasedDate;
private boolean printed;
#ManytoOne(name="TICKET_ID")
private Ticket ticket;
}
However, I wouldn't recommend using #OneToMany as this can create problems serializing too much data to JSON if you are returning this as JSON results or just lazily loading too much data by accident. You should always be able to work with just #ManyToOne as an example if you did not put the #OneToMany association query can be SELECT t FROM Discount d INNER JOIN d.ticket t WHERE d.percentage >= :discountPercentage
pals.
I have an issue with Hibernate's JPA implementation. I use spring-boot-starter-data-jpa and PostgreSql v9.
I have two entities with bidirectional connection via OneToMany & ManyToOne:
#Entity
public class ShoppingCart {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#Column(name = "name")
private String name;
#OneToMany(mappedBy = "shoppingCart", cascade = {CascadeType.ALL})
private List<Good> goods = new ArrayList<>();
public void addGood(Good good) {
good.setShoppingCart(this);
goods.add(good);
}
public Good removeGood(Good good) {
goods.remove(good);
good.setShoppingCart(null);
return good;
}
public ShoppingCart() {
}
public List<Good> getGoods() {
return goods;
}
public ShoppingCart(String name) {
this.name = name;
}
public Long getId() {
return id;
}
public String getName() {
return name;
}
}
And second entity is
#Entity
public class Good {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#Column(name = "name")
private String name;
#ManyToOne(fetch = FetchType.LAZY)
#JoinColumn(name = "cart_id")
#JsonIgnore
private ShoppingCart shoppingCart;
public ShoppingCart getShoppingCart() {
return shoppingCart;
}
public void setShoppingCart(ShoppingCart shoppingCart) {
this.shoppingCart = shoppingCart;
}
public Good(String name) {
this.name = name;
}
public Good() {
}
public Long getId() {
return id;
}
public String getName() {
return name;
}
}
Also I use CrudRepository to access ShoppingCart
public interface ShoppingCartRepository extends CrudRepository<ShoppingCart, Long> {}
And when I'm trying to fill existing cart I have two goods in my database. This is a code to add some goods into existing cart:
ShoppingCart cart = shoppingCartRepository.findOne(id);
cart.addGood(new Good("Butter"));
return shoppingCartRepository.save(cart);
In table "good" I have now two elements with different PKey and same data
5;"Butter";100
6;"Butter";100
Why it happens?
Also, when I'm trying to insert breakpoint at repository.save line, I see only one good in goods list in cart.
So, the problem is solved.
First way to solve is to make method with save code #Transactional.
Secon way is to use getGoods() instead of goods. We should change this code
public void addGood(Good good) {
good.setShoppingCart(this);
goods.add(good);
}
public Good removeGood(Good good) {
goods.remove(good);
good.setShoppingCart(null);
return good;
}
to this
public void addGood(Good good) {
good.setShoppingCart(this);
this.getGoods().add(good);
}
public Good removeGood(Good good) {
this.getGoods().remove(good);
good.setShoppingCart(null);
return good;
}
getGoods() here forces hibernate to update state of object and everything works fine.
As for me, I use both ways together
It happens because you create a new Good object without id. So Hibernate will generate a new id and persist the new object. If you don't want to create a new object, but only assign an already existing one, you either have to fetch the existing one from the database and assign it to the ShoppingCart oder add the ID if you create the new Good object.
I am trying to develop a web application and I was wondering if there is a way to utilize a foreign key without writing a lot of code.
My Trainees.java
#Entity
public class Trainees {
#Id
#GeneratedValue
private int traineesID;
private int groupsID;
#ManyToOne
#JoinColumn(name = "status_trainee")
private String status_TraineeID;
private int customersID;
private String name;
private String surname;
private String phoneDetails;
private String email;
public Trainees(){
}
public Trainees(String name, String surname, String phoneDetails, String email, int id, int groupsID, String status_TraineeID, int customersID) {
super();
this.name = name;
this.surname = surname;
this.email = email;
this.phoneDetails = phoneDetails;
this.groupsID = groupsID;
this.status_TraineeID = status_TraineeID;
this.customersID = customersID;
}
//getters and setters
#Override
public boolean equals(Object object) {
if (object instanceof Trainees){
Trainees contact = (Trainees) object;
return contact.traineesID == traineesID;
}
return false;
}
#Override
public int hashCode() {
return traineesID;
}
}
Status_Trainee.java
#Entity
public class Status_Trainee {
#Id
#GeneratedValue
private int status_traineeID;
private String value;
public Status_Trainee(){
}
public Status_Trainee(String value, int id) {
super();
this.value = value;
}
//getters and setters
#Override
public boolean equals(Object object) {
if (object instanceof Status_Trainee){
Status_Trainee value = (Status_Trainee) object;
return value.status_traineeID == status_traineeID;
}
return false;
}
#Override
public int hashCode() {
return status_traineeID;
}
}
Error: Caused by: org.hibernate.AnnotationException: #OneToOne or #ManyToOne on uaiContacts.model.Trainees.status_TraineeID references an unknown entity: String
So my aim is that using the Trainees table and class, I could retrieve the value of Status_Trainee table using the foreign key. For example: if foreign keys ID is 2, then it would retrieve a string from status_trainee table where primary key would match the foreign key ID.
I am using models, controlers, hibernate and angularjs to display to the view, I don't really want to pass the table through all this, I thought using something like ManyToOne or JoinColumns would retrieve the value?
Thanks for all the help!
You should add a reference to StatusTrainee in Trainee and annotate that with OneToMany, ManyToOne or OneToOne. Depending on which kind of relationship you will need a list of StatusTrainee or just a StatusTrainee.
Tip: dont use underscores in class names.
First of all, it is not recommended to use "_" in a class name when using hibernate. Hibernate uses underscores when accessing foreignKeys. So Lets Say you rename your class to: TraineeStatus and the id change it to traineeStatusId..
Secondly, You can use the Hibernate annotations for what you need. but first you need to know how the relation is:
#OneToMany : One Trainee can have lots of statuses
#ManytoOne : Many trainees can have the same status
#OneToOne : one Trainee Can only have one status and the other way around.
Try this:
#Entity
public class Trainees {
#Id
#GeneratedValue
private int traineesID;
private int groupsID;
#OneToOne
private TraineeStatus status;
private int customersID;
private String name;
private String surname;
private String phoneDetails;
private String email;
...
You can change the #OneToOne for the one you need..
Remember that hibernate will try to map this in your Trainees mysql table as status_traineeStatusId, so if you have this column (as an integer) at your trainess table you are done :)..
That is it..
Hope it helps