错误util.JDBCExceptionReporter-使用Hibernate ORM未为参数1指定值

Question

Below are my POJO's

class User extends AbstractDomainObject{
    private String username;
    private String password;

    //setter and getter
}

class Notification extends AbstractDomainObject{
    private String message;
    private Set<User> notificationFor;

    //setter and getter
}

class AbstractDomainObject{
    private long id;
    // setter and getter
}

Below are mapping's for above POJO

User.hbm.xml

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
    <class name="User" table="user">
        <id name="id" type="long" column="id">
            <generator class="native" />
        </id>

            <property name="username" type="string">
            <column name="username" />
        </property>

        <property name="password" type="string">
            <column name="password" />
        </property>
    </class>
 </hibernate-mapping>

Notification.hbm.xml

 <?xml version="1.0"?>
    <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
    <hibernate-mapping>

         <class name="Notification" table="notification">
            <id name="id" type="long" column="id">
                <generator class="native" />
            </id>

                <set name="notificationFor" table="user_notification" lazy="false" cascade="all">
            <key column="notification_id"/>
            <many-to-many unique="true" class="User" column="user_id"/>
            </set>

                <property name="message" type="string">
            <column name="message" />
            </property>
         </class>
    </hibernate-mapping>

I want list of notifications for given user. below is my daoimpl.

public List<Notification> getNotification(User user) {

        Session session = null;
        List<Notification> notifications = null;
        try {

            session = getSessionFactory().openSession();
            String queryString = "from Notification notification where notification.notificationFor IN (:user)";
            Query query = session.createQuery(queryString);
            query.setParameter("user", user);
            notifications = query.list();        

        } catch (Exception e) {

            e.printStackTrace();

        }

        return notifications;
    }

Above code snippet giving error at query.list() line. Error is ERROR util.JDBCExceptionReporter - No value specified for parameter 1 Any help will be appreciable. I don't know where I am wrong.

Answer 1

User is a user defined class which hibernate do not know about it. You should supply a type which is known by Hibernate. It may be String , Long , int .

I assume that User has a name field and the query will be performed accordingly.

query.setParameter("user", user.getName());

Furthermore, you should give the entity class to Query class. Query#setResultTransformer can be used.

Query query = session.createQuery(queryString).setResultTransformer(Transformers.aliasToBean(Notification.class));