1. Set method injection:
.xml configuration file:
<bean id="userDao" class="com.itlaobin.dao.impl.UserDaoImpl"></bean>
<bean id="userService" class="com.itlaobin.service.impl.UserserviceImpl">
<property name="userDao" ref="userDao"></property>
</bean>
set method:
private UserDao userDao;
public void setUserDao(UserDao userDao) {
this.userDao = userDao;
}
Presentation layer UserController
ApplicationContext app=new ClassPathXmlApplicationContext("applicationContext.xml");
Userservice userService = (Userservice) app.getBean("userService");
userService.save();
Injection of the p namespace in the set:
(1) Add in the namespace
xmlns:p="http://www.springframework.org/schema/p"
(2) Configuration file:
<bean id="userService" class="com.itlaobin.service.impl.UserserviceImpl" p:userDao-ref="userDao" />
2. (with parameters) construction method injection:
the realization of the service construction method with parameters
private UserDao userDao;
public UserserviceImpl(UserDao userDao) {
this.userDao = userDao;
}
public UserserviceImpl() {
}
Configuration file
<bean id="userDao" class="com.itheima.dao.impl.UserDaoImpl"></bean>
<bean id="userService" class="com.itheima.service.impl.UserserviceImpl">
<constructor-arg name="userDao" ref="userDao"></constructor-arg>
</bean>