<mapping resource="com/imooc/model/Seller.hbm.xml"/>
? ?<mapping resource="com/imooc/model/Customer.hbm.xml"/>等語句的使用
? 比如在這節(jié)課中，如果我創(chuàng)建了五條映射語句，<mapping resource="com/imooc/model/Seller.hbm.xml"/>
?<mapping resource="com/imooc/model/Customer.hbm.xml"/>
?<mapping resource="com/imooc/model/Commodity.hbm.xml"/>
?<mapping resource="com/imooc/model/Order.hbm.xml"/>
?<mapping resource="com/imooc/model/OrderItem.hbm.xml"/>
而沒有創(chuàng)建對應的5個持久化類以及映射文件，只有商家和顧客兩個。則junit測試

@Test

public void testFromClause(){

String hql = " from Customer ";

Query query = session.createQuery(hql);

List<Customer> customers = query.list();

for(Customer customer : customers){

System.out.println("name:"+customer.getName());

}

}

會拋出指示Query query = session.createQuery(hql);session.close();這兩行有空指針異常

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