java - Spring @Aspect 未正确 Autowiring

Question

我有以下代码:

package com.cooldomain.coolapp.application.rest.session;

import javax.annotation.PostConstruct;
import javax.servlet.http.HttpServletRequest;

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

@Aspect
@Component
public class SessionAspect
{
    @Autowired
    private HttpServletRequest request;

    @Autowired
    private SessionService sessionService;

    @PostConstruct
    public void init()
    {
        /*
        * XXX Note: On application startup this piece of code prints the right values and I can see that they have been autowired correctly:
        * ------------------------------------------------------------------------------------------------
        * request: Current HttpServletRequest
        * sessionService: com.cooldomain.coolapp.application.rest.session.SessionService@3700511f
        * ------------------------------------------------------------------------------------------------
        */
        System.out.println("request: " + request);
        System.out.println("sessionService: " + sessionService);
    }

    @Around("@annotation(com.cooldomain.coolapp.application.rest.session.SessionRequired) && within(com.cooldomain.coolapp.application..*)")
    public Object proceedWithValidSession(ProceedingJoinPoint joinPoint) throws Throwable
    {
        /*
        * XXX Note: But when I make a request to the annotated with @SessionRequired method i get the following output and hence a nullpointer exception afterwards:
        * ------------------------------------------------------------------------------------------------
        * request: null
        * sessionService: null
        * ------------------------------------------------------------------------------------------------
        */
        System.out.println("request: " + request);
        System.out.println("sessionService: " + sessionService);

        return setSessionAsFirstArgument(joinPoint);
    }

    private Object setSessionAsFirstArgument(ProceedingJoinPoint joinPoint) throws Throwable
    {
        Object[] args = joinPoint.getArgs();
        args[0] = sessionService.getSession(request);

        return joinPoint.proceed(args);
    }
}

所以问题是，当我启动应用程序时，所有内容都会正确自动连接，但是当我向引用方面的带注释方法发出请求时，自动连接字段会神奇地设置为 null。我不确定 spring 是否使用这个 bean 或者正在尝试创建另一个 bean...

注意:这段代码存在于其他两个项目中，并且绝对相同(复制/粘贴)，并且在那里它工作得很好，但在这里它中断了......我使用 spring 版本 4.1.5 和方面jrt 1.8.5，就像在其他两个项目中一样。

我已经完成了以下解决方法，该方法有效，但它很难看，我想将其删除:

package com.cooldomain.coolapp.application.rest.session;

import javax.annotation.PostConstruct;
import javax.servlet.http.HttpServletRequest;

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

@Aspect
@Component
public class SessionAspect
{
    @Autowired
    private HttpServletRequest request;

    @Autowired
    private SessionService sessionService;

    // WORKAROUND
    private static SessionAspect sessionAspect;

    @PostConstruct
    public void init()
    {
        /*
         * Note: On application startup this piece of code prints the right values and I can see that they have been autowired correctly:
         * ------------------------------------------------------------------------------------------------
         * request: Current HttpServletRequest
         * sessionService: com.cooldomain.coolapp.application.rest.session.SessionService@3700511f
         * ------------------------------------------------------------------------------------------------
         */
        System.out.println("request: " + request);
        System.out.println("sessionService: " + sessionService);

        // WORKAROUND
        sessionAspect = this;
    }

    @Around("@annotation(com.cooldomain.coolapp.application.rest.session.SessionRequired) && within(com.cooldomain.coolapp.application..*)")
    public Object proceedWithValidSession(ProceedingJoinPoint joinPoint) throws Throwable
    {
        /*
         * XXX Note: But when I make a request to the annotated with @SessionRequired method i get the following output and hence a nullpointer exception afterwards:
         * ------------------------------------------------------------------------------------------------
         * request: null
         * sessionService: null
         * ------------------------------------------------------------------------------------------------
         */
        System.out.println("request: " + request);
        System.out.println("sessionService: " + sessionService);

        // WORKAROUND
        return sessionAspect.setSessionAsFirstArgument(joinPoint);
    }

    private Object setSessionAsFirstArgument(ProceedingJoinPoint joinPoint) throws Throwable
    {
        Object[] args = joinPoint.getArgs();
        args[0] = sessionService.getSession(request);

        return joinPoint.proceed(args);
    }
}

有人知道如何解决这个问题吗？

Answer 1

.好吧，事实证明 Spring 不应该受到指责，它只创建了一个 bean。 我看到了项目 xml，有一个插件 aspectj-maven-plugin (aspectj-maven-plugin)，它在 spring 上下文之外创建该类的另一个实例，并且 @Aspect 使用此实例 - 而不是 spring 实例 如果可以只制作 spring bean，而不删除插件，将在网上寻找解决方案...也许配置中有一个排除选项