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javahibernatecriteriahibernate-criteria

Hibernate Criteria Query without Relationship Between Entities


I have two tables:

A (x, y, z, date1, date2)
B (t, date1, date2)

I want to execute a query like this:

SELECT A.x, A.y, A.z, A.date1
FROM   A, B 
WHERE  A.date1 < B.date1 
AND   (A.date2 is null or A.date2 <= B.date2 )
ORDER BY A.x DESC;

How can I do that using Hibernate Criteria?


Solution

  • String           dateIdValue   = "...";
    Class<?>         mainClass     = A.class;
    Class<?>         dateClass     = B.class;
    
    String           colDate1      = "date1";
    String           colDate2      = "date2";
    String           colDateId     = "id";
    
    Property         date1Prop     = Property.forName(colDate1);
    Property         date2Prop     = Property.forName(colDate2);
    
    DetachedCriteria date1Criteria = DetachedCriteria.forClass(dateClass)
                                                     .setProjection(date1Prop)
                                                     .add(Restrictions.eq(colDateId, dateIdValue));
    DetachedCriteria date2Criteria = DetachedCriteria.forClass(dateClass)
                                                     .setProjection(date2Prop)
                                                     .add(Restrictions.eq(colDateId, dateIdValue));
    
    Criteria         criteria      = getSession().createCriteria(mainClass)
                                    .add(date1Prop.lt(date1Criteria))
                                    .add(Restrictions.or(date2Prop.isNull(), date2Prop.le(date2Criteria)))
                                    .addOrder(Order.desc("x"));
    
    /*
        SELECT A.*
        FROM   A, P
        WHERE  A.date1 < P.date1
        AND   (A.date2 is null or A.date2 <= P.date2 )
        ORDER BY A.x DESC;
     */