Nsryjdtyk

I store an account Object in session when a user logging in. Now I want to realize that I would check if any account exists in session when each request proceeding. So I come up with using Spring AOP. Now test binding methods in Controllers:

@Aspect

public class AuthAspect {

    @Pointcut("execution(* com.bolaa.sentiment.controller..*.*(javax.servlet.http.HttpSession,..)) && args" +

            "(session,args)")

    public void around(HttpSession session, Object ... args) {

    }



    @Around("around(session,args)")

    public void checkLoggedIn(ProceedingJoinPoint pjp, HttpSession session, Object ... args) {

        System.out.println("Aspect start");

        try {

            pjp.proceed();

        } catch (Throwable throwable) {

            throwable.printStackTrace();

        }

        System.out.println("Aspect end");

    }

}

For example, a request as follows:

@RestController

@RequestMapping("/role")

public class RoleController {

    @Autowired

    public IRoleService iRoleService;



    @RequestMapping(value = "getRoles")

    public IPage<Role> getRoles(HttpSession session, Integer pageNum, Integer pageSize) {

        return iRoleService.selectListPage(pageNum, pageSize);

    }

}

When I get the Roles, there isn't any logs in console. It couldn't bind the method getRoles(session,..). How to correct the Pointcut by arguments with HttpSession first and omit the rest of the arguments?

Arguments matching is strict and bit complex - () matches a method that takes no parameters, whereas (..) matches any number (zero or more) of parameters. The (*) pattern matches a method that takes one parameter of any type.

But args limits matching to join points (the execution of methods when using Spring AOP) where the arguments are instances of the given types.

when specifying args need to specify all the arguments as that will be used to match correct method.

So change your pointcut as below -

@Pointcut("execution(* com.bolaa.sentiment.controller..*.*(..)) && args(session,pageNum, pageSize)")

First a few general remarks about your aspect code:

• An around advice needs to return something, if the intercepted method is not void, so the return type should be Object or something more specific. Otherwise the pointcut will not match.




• You should never just swallow exceptions or only log them, but actually re-throw them after logging, unless you handle them correctly and return a valid object or null.




• A method signature in AspectJ syntax like foo.bar..*.*(..) is a bit too verbose and can be abbreviated like foo.bar..*(..).




• The assumption that ignored arguments could be collected in an additional ... parameter and magically end up in an array is wrong. If you want to ignore something you can just use jokers like '*' or '..' instead, but not bind the ignored arguments to pointcut parameters.




• The assumption that you have to specify and bind all parameters, as shown by Amit Naik, is also wrong. You can do that, but do not have to.

So here is your solution:

package de.scrum_master.aspect;



import javax.servlet.http.HttpSession;



import org.aspectj.lang.ProceedingJoinPoint;

import org.aspectj.lang.annotation.Around;

import org.aspectj.lang.annotation.Aspect;

import org.aspectj.lang.annotation.Pointcut;



@Aspect

public class AuthAspect {

  @Pointcut("execution(* com.bolaa.sentiment.controller..*(..)) && args(session, ..)")

  public void myPointcut(HttpSession session) {}



  @Around("myPointcut(session)")

  public Object checkLoggedIn(ProceedingJoinPoint pjp, HttpSession session) throws Throwable {

    System.out.println("[START] " + pjp + " -> " + session);

    try {

      return pjp.proceed();

    }

    catch (Throwable throwable) {

      throwable.printStackTrace();

      throw throwable;

    }

    finally {

      System.out.println("[EXIT]  " + pjp + " -> " + session);

    }

  }

}

This prints something like the following on the console:

[START] execution(List com.bolaa.sentiment.controller.role.RoleController.getRoles(HttpSession, Integer, Integer)) -> com.bolaa.sentiment.controller.role.RoleController$1@7daf6ecc

[EXIT]  execution(List com.bolaa.sentiment.controller.role.RoleController.getRoles(HttpSession, Integer, Integer)) -> com.bolaa.sentiment.controller.role.RoleController$1@7daf6ecc