03Spring - 控制反转IOC入门案例

/**
 * 客户的业务接口
 */
public interface ICustomerService{
    /**
     * 保存客户
     */
    void saveCustomer();
}
/**
 * 客户业务层实现代码
 */
public class CustmoerServiceImpl implements ICustomerService{
    private ICustomerDao custmoerDao = new CustomerDaoImpl();
    @Override
    public void saveCustomer() {
        customerDao.saveCustomer();
    }
}
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/**
 * 客户的持久层接口
 */
public interface ICustomerDao{
    /**
     * 保存客户
     */
    void saveCustmoer();
}
/**
 * 客户的持久层实现类
 */
public class CustomerDaoImpl implements ICustomerDao{
    @Override
    public void saveCustmoer() {
        System.out.println("保存了用户");
    }
}

public class Client{
    public static void main(String[] args){
        //1.使用ApplicationContext接口，获取Spring容器
        ApplicationContext ac = new ClassPathXmlAPplicationContext("bean.xml");
        //2.根据bean的id获取对象
        ICustomerService cs = (ICustomerService)ac.getBean("customerService");
        System.out.println(cs);
        ICustomerDao cd = (ICustomerDao)ac.getBean("customerDao");
         System.out.println(cd);
    }
}