object references an unsaved transient instance -

Question

I receive following error when I save the object using Hibernate

object references an unsaved transient instance - save the transient instance before flushing

Answer 1

You should include cascade="all" (if using xml) or cascade=CascadeType.ALL (if using annotations) on your collection mapping.

This happens because you have a collection in your entity, and that collection has one or more items which are not present in the database. By specifying the above options you tell hibernate to save them to the database when saving their parent.

Answer 2

i get this error when i use

getSession().save(object)

but it works with no problem when I use

getSession().saveOrUpdate(object) 

Answer 3

For the sake of completeness: A

org.hibernate.TransientPropertyValueException 

with message

object references an unsaved transient instance - save the transient instance before flushing

will also occur when you try to persist / merge an entity with a reference to another entity which happens to be detached.

Answer 4

I also faced the same situation. By setting following annotation above the property made it solve the exception prompted.

The Exception I faced.

Exception in thread "main" java.lang.IllegalStateException: org.hibernate.TransientObjectException: object references an unsaved transient instance - save the transient instance before flushing: com.model.Car_OneToMany

To overcome, the annotation I used.

    @OneToMany(cascade = {CascadeType.ALL})
    @Column(name = "ListOfCarsDrivenByDriver")
    private List<Car_OneToMany> listOfCarsBeingDriven = new ArrayList<Car_OneToMany>();

What made Hibernate throw the exception:

This exception is thrown at your console because the child object I attach to the parent object is not present in the database at that moment.

By providing @OneToMany(cascade = {CascadeType.ALL}) , it tells Hibernate to save them to the database while saving the parent object.

Answer 5

To add my 2 cents, I got this same issue when I m accidentally sending null as the ID. Below code depicts my scenario (and OP didn't mention any specific scenario).

Employee emp = new Employee();
emp.setDept(new Dept(deptId)); // --> when deptId PKID is null, same error will be thrown
// calls to other setters...
em.persist(emp);

Here I m setting the existing department id to a new employee instance without actually getting the department entity first, as I don't want to another select query to fire.

In some scenarios, deptId PKID is coming as null from calling method and I m getting the same error.

So, watch for null values for PK ID

Answer 6

There are so many possibilities of this error some other possibilities are also on add page or edit page. In my case I was trying to save a object AdvanceSalary. The problem is that in edit the AdvanceSalary employee.employee_id is null Because on edit I was not set the employee.employee_id. I have make a hidden field and set it. my code working absolutely fine.

    @Entity(name = "ic_advance_salary")
    @Table(name = "ic_advance_salary")
    public class AdvanceSalary extends BaseDO{

        @Id
        @GeneratedValue(strategy = GenerationType.IDENTITY)
        @Column(name = "id")
        private Integer id;

        @ManyToOne(fetch = FetchType.EAGER)
        @JoinColumn(name = "employee_id", nullable = false)
        private Employee employee;

        @Column(name = "employee_id", insertable=false, updatable=false)
        @NotNull(message="Please enter employee Id")
        private Long employee_id;

        @Column(name = "advance_date")
        @DateTimeFormat(pattern = "dd-MMM-yyyy")
        @NotNull(message="Please enter advance date")
        private Date advance_date;

        @Column(name = "amount")
        @NotNull(message="Please enter Paid Amount")
        private Double amount;

        @Column(name = "cheque_date")
        @DateTimeFormat(pattern = "dd-MMM-yyyy")
        private Date cheque_date;

        @Column(name = "cheque_no")
        private String cheque_no;

        @Column(name = "remarks")
        private String remarks;

        public AdvanceSalary() {
        }

        public AdvanceSalary(Integer advance_salary_id) {
            this.id = advance_salary_id;
        }

        public Integer getId() {
            return id;
        }

        public void setId(Integer id) {
            this.id = id;
        }

        public Employee getEmployee() {
            return employee;
        }

        public void setEmployee(Employee employee) {
            this.employee = employee;
        }


        public Long getEmployee_id() {
            return employee_id;
        }

        public void setEmployee_id(Long employee_id) {
            this.employee_id = employee_id;
        }

    }