I try to get a Set from many-to-one and I get an empty set. What is wrong?
Class A{

Set classB = new HashSet


* @hibernate.set
* cascade="all"
* lazy="true"
* @hibernate.collection-key
* column="A_ID
* @hibernate.collection-one-to-many
class="A_B"

getClassB(){
return classB
}

}

Class B{

Set classA = new HashSet

* @hibernate.set
* cascade="all"
* lazy="true"
* @hibernate.collection-key
* column="B_ID
* @hibernate.collection-one-to-many
class="A_B"

getClassA(){
return classA
}
}


Class A_B{

ClassA a;
ClassB b;
String str;

* @hibernate.many-to-one
* column="A_ID"
ClassA getA(){
return a;
}


* @hibernate.many-to-one
* column="B_ID"
ClassB getB(){
return b;
}


}



When I try to get the Set of ClassB from ClassA in ClassC I get an empty Set

ClassA a1 = new ClassA();
a1.getClassB()

What is wrong?