One-To-Many in Hibernate

CREATE TABLE FATHER (   
    ID CHAR(32) NOT NULL,   
    NAME CHAR(32) NOT NULL,   

    PRIMARY KEY(id)   
)   

CREATE TABLE SON (   
    ID CHAR(32) NOT NULL,   
    NAME CHAR(32) NOT NULL,   

    FATHER_ID CHAR(32) NOT NULL,   

    PRIMARY KEY(id)   
)   
ALTER TABLE SON ADD FOREIGN KEY FATHER_ID REFERENCE FATHER(ID);

Father.hbm.xml

<set name="children" lazy="true" inverse="true">   
    <key>
        <!-- Son.father_id -->
        <column name="FATHER_ID" not-null="true" />   
    </key>
    <one-to-many class="com.zero.demo.Son" />   
</set>

Son.hbm.xml

<many-to-one column="FATHER_ID" name="father" class="com.zero.demo.Father" not-null="true" cascade="none" />