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How to use setProjection correctly?

I only want to get certain columns in my UserAccount class, so I have below code:

UserAccount aUser = (UserAccount)currentSession().createCriteria(UserAccount.class)
                        /*  .setProjection(Projections.projectionList()
                                    .add(Projections.property("id"))
                                    .add(Projections.property("username"))
                                    .add(Projections.property("email"))
                                    .add(Projections.property("displayname"))) */
                            .add(Restrictions.eq("email", email))
                            .add(Restrictions.eq("password", password))
                            .add(Restrictions.eq("enabled", true))
                            .add(Restrictions.eq("role", Role.CUSTOMER))
                            .uniqueResult();
    System.out.println(aUser);
    return aUser;

I got zero in return. But if I comment out setProjections, I get the user with all properties. How can I use setProjection correctly in this case?

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2 answers


It returns an array of objects, so the code should be:



Object[] rows = (Object[]) session
        .createCriteria(UserAccount.class)
        .setProjection(
                Projections.projectionList()
                        .add(Projections.property("id"))
                        .add(Projections.property("username"))
                        .add(Projections.property("email"))
                        .add(Projections.property("displayname")))
        .add(Restrictions.eq("email", email))
        .add(Restrictions.eq("password", password))
        .add(Restrictions.eq("enabled", true))
        .add(Restrictions.eq("role", Role.CUSTOMER))
        .uniqueResult();
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With projections, we have to use result transformation and anti-aliasing :

UserAccount aUser = (UserAccount)currentSession()
    // FROM
    .createCriteria(UserAccount.class)
    // WHERE
    .add(Restrictions.eq("email", email))
    .add(Restrictions.eq("password", password))
    .add(Restrictions.eq("enabled", true))
    .add(Restrictions.eq("role", Role.CUSTOMER))
    // SELECT with alias
    .setProjection(Projections.projectionList()
       .add(Projections.property("id"),"id")             // alias is a must for
       .add(Projections.property("username"),"username") // result transformer
       .add(Projections.property("email"),"email")
       .add(Projections.property("displayname"),"displayname")
    )
    // here we go - this will convert projection into entity
    .setResultTransformer(Transformers.aliasToBean(UserAccount.class))
    .uniqueResult();


Check:

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