实例说明IoC注入方式
IoC有3种注入方式:接口注入、Setter方法注入、构造器注入。由于接口注入不推荐使用,所以只介绍setter方法注入和构造器注入(后面介绍)。
利用spring一步一步搭建起一个例子(本人采用eclipse)
/**
* Dao主要做数据库的交互工作
* Modle 是模型 存放你的实体类
*Service 做相应的业务逻辑处理
*Action是一个控制器
* @author syw
*
*/
Bean.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-2.5.xsd">
<bean id="u" class="com.dao.impl.UserDaoImpl">
</bean>
<bean id="userService" class="com.service.UserService">
<property name="userDAO" ref="u" />
</bean>
</beans>
modle:实体类
package com.model;
public class User {
private String username;
private String password;
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
}
Dao 数据库
package com.dao;
import com.model.User;
public interface UserDAO {
public void saveMySql(User user);
public void saveOracle(User user);
}
DaoImpl 实现(数据不一样,不一样的实现)
package com.dao.impl;
import com.dao.UserDAO;
import com.model.User;
public class UserDaoImpl implements UserDAO{
@Override
public void saveMySql(User user) {
System.out.println("Mysql: " + user.getUsername());
}
@Override
public void saveOracle(User user) {
System.out.println("Oracle: " + user.getPassword());
}
}
service 业务逻辑处理
package com.service;
import com.dao.UserDAO;
import com.model.User;
public class UserService {
private UserDAO userDAO;
public void add(User user) {
userDAO.saveMySql(user);
}
public UserDAO getUserDAO() {
return userDAO;
}
public void setUserDAO(UserDAO userDAO) {
this.userDAO = userDAO;
}
}
service 测试类
package com.service;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.model.User;
/**
* Dao主要做数据库的交互工作
* Modle 是模型 存放你的实体类
*Service 做相应的业务逻辑处理
*Action是一个控制器
* @author tao.zeng
*
*/
public class UserServiceTest {
@Test
public void testAdd() throws Exception {
ApplicationContext ctx = new ClassPathXmlApplicationContext("beans.xml");
UserService service = (UserService)ctx.getBean("userService");
User u = new User();
u.setUsername("syw");
u.setPassword("syw");
service.add(u);
}
}
代码运行:Mysql: syw