從AOP建議中設置變量

Question

我使用AOP建議將User對象轉換爲Owner對象。轉換是在建議中完成的，但我想將該對象傳遞給調用者。

@Aspect 
public class UserAuthAspect { 
    @Inject 
    private OwnerDao ownerDao; 

    @Pointcut("@annotation(com.google.api.server.spi.config.ApiMethod)") 
    public void annotatedWithApiMethod() { 
    } 

    @Pointcut("execution(* *.*(.., com.google.appengine.api.users.User)) && args(.., user)") 
    public void allMethodsWithUserParameter(User user) { 
    } 

    @Before("annotatedWithApiMethod() && allMethodsWithUserParameter(user)") 
    public void checkUserLoggedIn(com.google.appengine.api.users.User user) 
      throws UnauthorizedException { 
     if (user == null) { 
      throw new UnauthorizedException("Must log in"); 
     } 
     Owner owner = ownerDao.readByUser(user); 
    } 
} 

一類以建議的方法：

public class RealEstatePropertyV1 { 
    @ApiMethod(name = "create", path = "properties", httpMethod = HttpMethod.POST) 
    public void create(RealEstateProperty property, User user) throws Exception { 
     Owner owner = the value set by the advice 
    } 
} 

Answer 1

我不知道，如果是做正確的方式，可以隨意發表評論。我創建了一個接口Authed及其實現AuthedImpl。

public interface Authed { 
    void setOwner(Owner owner); 
} 

然後我做了RealEstatePropertyV1從AuthedImpl延伸。我爲從AuthedImpl延伸的所有類添加了切入點，並且還更改了切入點，以便可以訪問目標。

@Pointcut("execution(* *..AuthedImpl+.*(..))") 
public void extendsAuthedImpl() { 
} 

@Pointcut("execution(* *.*(.., com.google.appengine.api.users.User)) && args(.., user) && target(callee)") 
public void allMethodsWithUserParameter(User user, Authed callee) { 
} 

最後建議使用所有切入點：

@Before("annotatedWithApiMethod() && allMethodsWithUserParameter(user, callee) && extendsAuthedImpl()") 
public void checkUserLoggedIn(com.google.appengine.api.users.User user, 
     Authed callee) throws UnauthorizedException { 
    System.out.println(callee.getClass()); 
    if (user == null) { 
     throw new UnauthorizedException("Must log in"); 
    } 
    Owner owner = ownerDao.readByUser(user); 
    callee.setOwner(owner); 
}