Need help in Hibernate

Question

Below is the table

CREATE TABLE MyTable(
  'a_id' varchar(50) NOT NULL,
  'b_id' varchar(100) NOT NULL,
  'my_field' varchar(1) DEFAULT '0',
  PRIMARY KEY ('a_id','b_id'));

Values will be

a_id   -   b_id   -   my_field
aa   -   b1   -   N
aa-b2-N
aa-b3-Y
aa-b5-N
pp-q1-Y
pp-q2-N
pp-q3-N
pp-q4-B    

I want to have two Java beans as

Pojo1.java

private String aId
private List<Pojo2> pojo2

Pojo2.java

private String bId
private boolean myField

I want to retrieve the a_id for a given b_id (I'm am able to retrieve this) I want to retrieve the List of pojo2 for a single a_id (Have issue with this)

My Java code which throws

[b]java.lang.ClassCastException: [Ljava.lang.Object; cannot be cast to pojo2[/b]

try {
    session = // create Hibernate session;
    String query = "select x.bId,x.myField from MyTable x where x.aId=?";
    Query queryObj = session.createQuery(query);
    queryObj.setString(0, "value to aId");
    Pojo2 mypojo2 = (Pojo2) queryObj.list();

} catch (Exception e) {
} finally {
    close the connection
}

Below is the hibernate file for MyTable

<hibernate-mapping auto-import="true" default-lazy="false">
<class name="com.db.beans.MyTable" table="MYTABLE">
<composite-id>
    <key-property name="aId" type="string" column="a_id" length="100"/>
    <key-property name="bId" type="string" column="b_id" length="100"/>
</composite-id>
<property  name="myField"  type="string"    column="my_field" length="1"   />
</class>
</hibernate-mapping>

Please help in correcting my mapping file or Java code.

Answer 1

queryObj.list() returns a list. You can't cast a list to a single Pojo2. If your query and mapping are right, then you'll be able to use

Pojo2 mypojo2 = (Pojo2) (queryObj.list().get(0));