hibernate多对多删除被控方时出现异常解决

 ProuductItem 和 OtmsCharge是多对多关系，OtmsCharge是主控方。

主要的映射代码如下

ProductItem:

<set name="charges" table="ChargeDetail" inverse="true"><key column="productItem"></key><many-to-many column="chargeId" class="com.xycentre.otms.usermanager.model.OtmsCharge"></many-to-many></set>

OtmsCharge:

<set name="productItems" table="ChargeDetail"><key column="chargeId"/><many-to-many column="productItem" class="com.xycentre.otms.model.ProductItem"></many-to-many></set>

直接删除ProductItem会发生异常，正确的删除方法是：

public void unbindProductItem(Long piId){ if(piId < 0)return; Object piObj = this.getHibernateTemplate().get(ProductItem.class, piId); if(piObj != null && piObj instanceof ProductItem){ ProductItem pi = (ProductItem)piObj; Set<OtmsCharge> charges = pi.getCharges(); for(OtmsCharge charge : charges){ charge.getProductItems().remove(pi); } this.getHibernateTemplate().delete(pi); } }