not-null property references a null or transient value

Question

Facing trouble in saving parent/child object with hibernate. Any idea would be highly appreciated.

org.hibernate.PropertyValueException: not-null property references a null or transient value: example.forms.InvoiceItem.invoice     at org.hibernate.engine.Nullability.checkNullability(Nullability.java:100)         .... (truncated) 

hibernate mapping:

<hibernate-mapping package="example.forms">     <class name="Invoice" table="Invoices">         <id name="id" type="long">             <generator class="native" />         </id>         <property name="invDate" type="timestamp" />         <property name="customerId" type="int" />         <set cascade="all" inverse="true" lazy="true" name="items" order-by="id">             <key column="invoiceId" />             <one-to-many class="InvoiceItem" />         </set>     </class>     <class name="InvoiceItem" table="InvoiceItems">         <id column="id" name="itemId" type="long">             <generator class="native" />         </id>         <property name="productId" type="long" />         <property name="packname" type="string" />         <property name="quantity" type="int" />         <property name="price" type="double" />         <many-to-one class="example.forms.Invoice" column="invoiceId" name="invoice" not-null="true" />     </class> </hibernate-mapping> 

InvoiceManager.java

class InvoiceManager {      public Long save(Invoice theInvoice) throws RemoteException {         Session session = HbmUtils.getSessionFactory().getCurrentSession();         Transaction tx = null;         Long id = null;         try {             tx = session.beginTransaction();             session.persist(theInvoice);             tx.commit();             id = theInvoice.getId();         } catch (RuntimeException e) {             if (tx != null)                 tx.rollback();             e.printStackTrace();             throw new RemoteException("Invoice could not be saved");         } finally {             if (session.isOpen())                 session.close();         }         return id;     } } 

Invoice.java

public class Invoice implements java.io.Serializable {     private Long id;     private Date invDate;     private int customerId;     private Set<InvoiceItem> items;      public Long getId() {         return id;     }     public Date getInvDate() {         return invDate;     }     public int getCustomerId() {         return customerId;     }     public Set<InvoiceItem> getItems() {         return items;     }     void setId(Long id) {         this.id = id;     }     void setInvDate(Date invDate) {         this.invDate = invDate;     }     void setCustomerId(int customerId) {         this.customerId = customerId;     }     void setItems(Set<InvoiceItem> items) {         this.items = items;     } } 

InvoiceItem.java

public class InvoiceItem implements java.io.Serializable {     private Long itemId;     private long productId;     private String packname;     private int quantity;     private double price;     private Invoice invoice;      public Long getItemId() {         return itemId;     }     public long getProductId() {         return productId;     }     public String getPackname() {         return packname;     }     public int getQuantity() {         return quantity;     }     public double getPrice() {         return price;     }     public Invoice getInvoice() {         return invoice;     }     void setItemId(Long itemId) {         this.itemId = itemId;     }     void setProductId(long productId) {         this.productId = productId;     }     void setPackname(String packname) {         this.packname = packname;     }     void setQuantity(int quantity) {         this.quantity = quantity;     }     void setPrice(double price) {         this.price = price;     }     void setInvoice(Invoice invoice) {         this.invoice = invoice;     } } 

Answer 1

for followers, this error message can also mean "you have it referencing a foreign object that hasn't been saved to the DB yet" (even though it's there, and is non null).

Answer 2

Every InvoiceItem must have an Invoice attached to it because of the not-null="true" in the many-to-one mapping.

So the basic idea is you need to set up that explicit relationship in code. There are many ways to do that. On your class I see a setItems method. I do NOT see an addInvoiceItem method. When you set items, you need to loop through the set and call item.setInvoice(this) on all of the items. If you implement an addItem method, you need to do the same thing. Or you need to otherwise set the Invoice of every InvoiceItem in the collection.