springboot的cglib的代理问题

Question

我在springboot项目中通过@configuration和@Bean注解添加了一个filter，可以正常工作；
之后想用AOP使该filter中每个方法被调用前都会输出log,但是在tomcat启动过程中这个filter（已经被cglib增强过了）的logger字段（该logger字段被声明为final,定义在org.springframework.web.filter.GenericFilterBean.java）为null抛出异常，不明白为什么，麻烦大家帮忙看看，谢谢。

调试中filter被cglib增强后的截图：

切面类：

package io.spring.infrastructure;
import org.aspectj.lang.annotation.Aspect;
import org.springframework.stereotype.Component;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

@Component
@Aspect

public class ShowLogger {
    Logger logger = LoggerFactory.getLogger(getClass());
    @Before("within(io.spring.api.security.*)")
    public void outputLog(JoinPoint joinPoint) {
        logger.info("@@@@@@@@@@@@@@@@: "+
                joinPoint.getSignature());

    }
}    

Filter类：

package io.spring.api.security;

import io.spring.core.service.JwtService;
import io.spring.core.user.UserRepository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.security.web.authentication.WebAuthenticationDetailsSource;
import org.springframework.web.filter.OncePerRequestFilter;

import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.Collections;
import java.util.Optional;

//@SuppressWarnings("SpringJavaAutowiringInspection")
public class JwtTokenFilter extends OncePerRequestFilter {

    @Autowired
    private UserRepository userRepository;

    @Autowired
    private JwtService jwtService;

    private String header = "Authorization";

    @Override
    protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain) throws ServletException, IOException {
        getTokenString(request.getHeader(header)).ifPresent(token -> {
            jwtService.getSubFromToken(token).ifPresent(id -> {
                if (SecurityContextHolder.getContext().getAuthentication() == null) {
                    userRepository.findById(id).ifPresent(user -> {
                        UsernamePasswordAuthenticationToken authenticationToken = new UsernamePasswordAuthenticationToken(
                            user,
                            null,
                            Collections.emptyList()
                        );
                        authenticationToken.setDetails(new WebAuthenticationDetailsSource().buildDetails(request));
                        SecurityContextHolder.getContext().setAuthentication(authenticationToken);
                    });
                }
            });
        });

        filterChain.doFilter(request, response);
    }

    private Optional<String> getTokenString(String header) {
        if (header == null) {
            return Optional.empty();
        } else {
            String[] split = header.split(" ");
            if (split.length < 2) {
                return Optional.empty();
            } else {
                return Optional.ofNullable(split[1]);
            }
        }
    }
}

配置类：

package io.spring.api.security;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.HttpMethod;
import org.springframework.http.HttpStatus;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
import org.springframework.security.config.http.SessionCreationPolicy;
import org.springframework.security.web.authentication.HttpStatusEntryPoint;
import org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter;
import org.springframework.web.cors.CorsConfiguration;
import org.springframework.web.cors.CorsConfigurationSource;
import org.springframework.web.cors.UrlBasedCorsConfigurationSource;

import static java.util.Arrays.asList;

@Configuration
@EnableWebSecurity
public class WebSecurityConfig extends WebSecurityConfigurerAdapter {

    @Value("${spring.h2.console.enabled:false}")
    private boolean h2ConsoleEnabled;

    @Bean
    public JwtTokenFilter jwtTokenFilter() {
        JwtTokenFilter T = new JwtTokenFilter();
        return T;
    }

    @Override
    protected void configure(HttpSecurity http) throws Exception {

        if (h2ConsoleEnabled)
            http.authorizeRequests()
                .antMatchers("/h2-console", "/h2-console/**").permitAll()
                .and()
                .headers().frameOptions().sameOrigin();

        http.csrf().disable()
            .cors()
            .and()
            .exceptionHandling().authenticationEntryPoint(new HttpStatusEntryPoint(HttpStatus.UNAUTHORIZED))
            .and()
            .sessionManagement().sessionCreationPolicy(SessionCreationPolicy.STATELESS).and()
            .authorizeRequests()
            .antMatchers(HttpMethod.OPTIONS).permitAll()
            .antMatchers(HttpMethod.GET, "/articles/feed").authenticated()
            .antMatchers(HttpMethod.POST, "/users", "/users/login").permitAll()
            .antMatchers(HttpMethod.GET, "/articles/**", "/profiles/**", "/tags").permitAll()
            .anyRequest().authenticated();

        http.addFilterBefore(jwtTokenFilter(), UsernamePasswordAuthenticationFilter.class);
    }

    @Bean
    public CorsConfigurationSource corsConfigurationSource() {
        final CorsConfiguration configuration = new CorsConfiguration();
        configuration.setAllowedOrigins(asList("*"));
        configuration.setAllowedMethods(asList("HEAD",
            "GET", "POST", "PUT", "DELETE", "PATCH"));
        // setAllowCredentials(true) is important, otherwise:
        // The value of the 'Access-Control-Allow-Origin' header in the response must not be the wildcard '*' when the request's credentials mode is 'include'.
        configuration.setAllowCredentials(true);
        // setAllowedHeaders is important! Without it, OPTIONS preflight request
        // will fail with 403 Invalid CORS request
        configuration.setAllowedHeaders(asList("Authorization", "Cache-Control", "Content-Type"));
        final UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
        source.registerCorsConfiguration("/**", configuration);
        return source;
    }
}

Answer 1

stackoverflow传送门: https://stackoverflow.com/que...

简单来说, CGLib是生成一个委托类, 用来代理原类型的非final方法. 委托类中的属性为null是正常的. 你需要做的应该是把被代理类的方法上的final关键字去掉. 获取logger可以调用getLogger()方法.