Spring（13）：新增功能：超市订单的供应商表查询 and 根据供应商名称查询供应商信息--解释（下）

2017/12/31

承接上文：Spring（13）：新增功能：超市订单的供应商表查询 and 根据供应商名称查询供应商信息--功能实现（上）（http://blog.youkuaiyun.com/qq_29166327/article/details/78943953）

Spring框架下的相关函数：

1、ClassPathXmlApplicationContext构造方法：

ClassPathXmlApplicationContext ctx = new ClassPathXmlApplicationContext("applicationContext-mybatis.xml");

ClassPathXmlApplicationContext

public ClassPathXmlApplicationContext(String configLocation)
                               throws BeansException

Create a new ClassPathXmlApplicationContext, loading the definitions from the given XML file and automatically refreshing the context.

Parameters:

configLocation - resource location

Throws:

BeansException - if context creation failed

2、getBean()方法：

ProviderService providerService = (ProviderService) ctx.getBean("providerServiceImpl");

getBean

public Object getBean(String name)
               throws BeansException

Description copied from interface: BeanFactory

Return an instance, which may be shared or independent, of the specified bean.

This method allows a Spring BeanFactory to be used as a replacement for the Singleton or Prototype design pattern. Callers may retain references to returned objects in the case of Singleton beans.

Translates aliases back to the corresponding canonical bean name. Will ask the parent factory if the bean cannot be found in this factory instance.

Specified by:

getBean in interface  BeanFactory

Parameters:

name - the name of the bean to retrieve

Returns:

an instance of the bean

Throws:

NoSuchBeanDefinitionException - if there is no bean definition with the specified name

BeansException - if the bean could not be obtained

sqlSession 类的相关函数：

【根据查询是否需要传参来确定】

1、selectList

<E> List<E> selectList(String statement)

Retrieve a list of mapped objects from the statement key and parameter.

Type Parameters:

E - the returned list element type

Parameters:

statement - Unique identifier matching the statement to use.

Returns:

List of mapped object

或：

2、selectList

<E> List<E> selectList(String statement,
                       Object parameter)

Retrieve a list of mapped objects from the statement key and parameter.

Type Parameters:

E - the returned list element type

Parameters:

statement - Unique identifier matching the statement to use.

parameter - A parameter object to pass to the statement.

Returns:

List of mapped object