Putting down here how I implemented this. Basically we need to make a Hibernate Component (read @Embeddable object) out of the set of columns we need to query on and embed it in the main Entity.
The group of columns can be combined as below:
@Embeddable
public class CompositeColumns{
private String col1;
private String col2;
//Empty constructor is required by Hibernate for instantiation
public CompositeColumns(){
}
public CompositeColumns(String col1, String col2){
this.col1 = col1;
this.col2 = col2;
}
@Column(name="COL1")
public String getCol1(){
}
...
...
//Rest of getters and setters
}
Embed the above in your main entity class as below:
@Entity
public class MyEntity{
@Id
private Integer id;
private String col3;
private String col4
@Embedded
private CompositeColumns pairedCol1Col2;
...
...
//Getters Setters
}
The query would then look as below:
List<CompositeColumns> cols = //get a list of CompositeColumns type
Query query=session.createQuery( "from MyEntity where pairedCol1Col2 in (:list)" );
query.setParameterList( "list", list );
This does the job.
Note: I ran this on an Oracle database