실습

1. 기본 프로그램 완성

Board.java

Write.java

MainApp.java

2. 강결합
Write.java -> FreeWrite.java변경
Board.java에서 일일이 코드 변경해주어야함
board.java
public void setWrite(Write write){     this.write = write;  }	public void setWrite(FreeBoardWrite write){     this.write = write;  }
public Board(){     this.setWrite(new Write());  }	public Board(){     this.setWrite(new FreeBoardWrite write));  }

3. 약결합 - 팩토리메서드 디자인, 인터페이스
팩토리메서드디자인 패턴으로 변경
static 메서드가 내부적으로 객체 구현하여 반환
반환할 객체만 변경해주면 Board.java에서 수정할 코드는 없다.
public class Factory{      public statis Write getWrite Instance(){         retrurn new FreeBoardWrite();      }      public static Board getBoardInstance(){         return new BoardCafe();      }  }	Board board = Factory.getBoardInstance();  public BoardCafe(){     this.setWrite(Factory.getWriteInstance());  }
인터페이스를 작성하여 상속하도록 함

4. Spring Application으로의 전환

1. resource/spring/springcontext4.xml

2. 빈 생성     <bean id ="board" class="part4.BoardCafe"/>

3. import org.springframwork.context.ApplicationContext;       ....     public static void main(String[] args){         ApplicationContext ac = new GenericXmlApplicationContext;         Board board = ac.getBean("board",Boardclass);         board.boardWrite();     }

5. @Autowired 이용한 DI

1. 자동 주입 - type 기준

2. 메서드

3. 객체

6. @Qualifier

1. @Autowired     @Qualifier("qnaWrite")

7. @Resource

1. 자동 주입 - name기준

8. component-scan

1. <context:component-scan base-package="part9" />

2. @Component("qnaWrite")

9. 전처리기
<beans>         <context:annotation-config>         <bean id="board" class="part5.BoardCafe" init-method="init"/>  </beans>
<beans>         <context:annotation-config>         <bean id="board" class="part5.BoardCafe"/>  </beans>	@PostConstruct  public void init(){      this.setsBoardName("Free Board");  }

10. AOP

1. AOP 라이브러리 추가  <dependency>     <groupId>org.springframework</groundId>     <artifactId>spring-aop</artifactId>  </dependency>  <dependency>     <groupId>org.aspectj</groupId>     <artifactId>aspectjweaver</artifactId>     <version>1.8.9</version>  </dependency>

2.    <beans>     <aop:config>         <aop:aspect ref="profiler">            <aop:pointcut id="publicMethod" expression="execution(public * part11..*(..))"/>            <aop:around pointcut-ref="publicMethod" method="trace"/>         </aop:aspect>     </aop:config>   </beans>