1.构造方法造对象
<!--方式一：构造方法实例化bean-->
<bean id="bookDao" class="com.itheima.dao.impl.BookDaoImpl"/>
public interface BookDao {
public void save();
}
import com.itheima.dao.BookDao;
public class BookDaoImpl implements BookDao {
public BookDaoImpl() {
System.out.println("book dao constructor is running ....");
}
public void save() {
System.out.println("book dao save ...");
}
}
import com.itheima.dao.BookDao;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class AppForInstanceBook {
public static void main(String[] args) {
ApplicationContext ctx = new ClassPathXmlApplicationContext("applicationContext.xml");
BookDao bookDao = (BookDao) ctx.getBean("bookDao");
bookDao.save();
}
}
运行结果
book dao constructor is running ....
book dao save ...
