Hibernate Join query to fetch the data in Java?

Question

I am new to Hibernate and Java server side. I have mapped MySQL table in Java using javax.persistence annotation. I have two tables:

order_header
In this table, I have
order_number(primary_key),total_order_value,delivery_charge,order_time columns.

order_details
In this table, I have
order_number,product_code,price columns.

In order_header the order_number is primary key.

For Each order_number there are n number of products in order_details table.
How can I combine both these tables?
What is the Query to get the value like Final Output

For Example :

Order Headers Table

Order_number     total_order_value     delivery_charge      order_time
----------------------------------------------------------------------
   25                2550                     50             03:20:50
   36                350                      50             03:20:50
----------------------------------------------------------------------

Order_headers.java

@Entity
@Table(name = "order_headers")
public class Order_headers {

@Id @GeneratedValue
@Column(name = "order_number")
private int order_number;

@Column(name = "total_order_value")
private double order_value;

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

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

//here getter and setter methods
}

Order_details

Order_number     product_code     price
---------------------------------------
    25               235          1500
    25               240          1000
    36               50           40
    36               96           60
    36               150          200    

Order_details.java

@Entity
@Table(name = "order_details")
public class Order_details {

@Column(name = "Order_number")
private int Order_number;

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

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

//here getter and setter methods
}

I don't know how to write the combined query in Hibernate to get the details like final output.

Final Output

Order_number     total_order_value     product_value   delivery_charge      order_time
---------------------------------------------------------------------------------------
   25                2550                   2500             50             03:20:50
   36                350                    300              50             03:20:50
---------------------------------------------------------------------------------------

Please help me to solve this issue.

Answer 1

you have to add relationship between Order_headers and Order_details one to many in hibernate you can achieve this by following code in your Order_headers.java

@OneToMany(mappedBy = "Order_number", fetch = FetchType.LAZY)
private List<Order_details> orderDetailList;

//add getter and setter methods for orderDetailList.

once you add this code now you can write Criteria like

Criteria criteria = session.createCriteria(Order_headers.class);
criteria.setFetchMode("Order_details",FetchMode.JOIN);
List<Order_headers> list = criteria.list();

or you can Writer HQL like

session.createQuery("from Order_headers cont join cont.Order_details where cont.id=1");

or you can also write SQL Query in case you want to writer SQL Query no need of adding property orderDetailList in Order_headers.java here is SQL

session.createSQLQuery("SELECT * FROM Order_headers order JOIN Order_details details ON order.order_number = details.order_number");