请高手写出这个方法..谢谢(只是根据id来修改的方法,返回int即可)

<hibernate-mapping>
    <class name="ssssss.begger.bug.entity.Product" table="product" schema="dbo" catalog="epai">
        <id name="id" type="java.lang.Integer">
            <column name="id" />
            <generator class="native" />
        </id>
        <property name="pname" type="java.lang.String">
            <column name="pname" length="50" />
        </property>
        <property name="xinghao" type="java.lang.String">
            <column name="xinghao" length="20" />
        </property>
        <property name="guige" type="java.lang.String">
            <column name="guige" length="100" />
        </property>
        <property name="price" type="java.lang.Double">
            <column name="price" scale="4" />
        </property>
        <property name="startTime" type="java.util.Date">
            <column name="startTime" length="23" />
        </property>
        <property name="stopTime" type="java.util.Date">
            <column name="stopTime" length="23" />
        </property>
        <property name="res" type="java.lang.String">
            <column name="res" length="200" />
        </property>
        <property name="ptype" type="java.lang.Integer">
            <column name="ptype" />
        </property>
        <property name="bimage" type="java.lang.String">
            <column name="bImage" length="50" />
        </property>
        <property name="simage" type="java.lang.String">
            <column name="sImage" length="50" />
        </property>
    </class>
</hibernate-mapping>-----本人想用hql写一个根据id来修改上面实体中的某一行信息的方法，经过努力还是失败
-----请高手写出这个方法..谢谢(只是根据id来修改的方法,返回int即可);