我试图在Spring中实现一个非常简单的自定义身份验证过程的示例，以便更好地理解这个概念。
我以为我现在已经准备好了一切，但是发送一个请求来测试我实现的东西，结果导致了一个NullPointerException，可以追溯到 this.getAuthenticationManager（） 在我的自定义过滤器中返回null。但是我不明白为什么。很不幸，这个非常相似的现有问题并没有真正帮助我。所以我会感谢帮助;这里是我认为最相关的课程，如果还需要的话，请随时询问。

• MyAuthenticationFilter*（基于用户名密码AuthenticationFilter的源代码），错误发生在以下代码的最后一行：

public class MyAuthenticationFilter extends AbstractAuthenticationProcessingFilter {

    public MyAuthenticationFilter() {
        super(new AntPathRequestMatcher("/login", "POST"));
    }

    @Override
    public Authentication attemptAuthentication(HttpServletRequest request, HttpServletResponse response) throws AuthenticationException {
            if (!request.getMethod().equals("POST")) {
                throw new AuthenticationServiceException(
                        "Authentication method not supported: " + request.getMethod());
            }

            String username = request.getParameter("username");
            String password = request.getParameter("password");
            String secondSecret = request.getParameter("secondSecret");

            if (username == null) {
                username = "";
            }

            if (password == null) {
                password = "";
            }

            username = username.trim();

            MyAuthenticationToken authRequest = new MyAuthenticationToken(username, new MyCredentials(password, secondSecret));

            return this.getAuthenticationManager().authenticate(authRequest);
    }
}

我的配置类：

@Configuration
@EnableWebSecurity
@EnableWebMvc
@ComponentScan
public class AppConfig extends WebSecurityConfigurerAdapter {
    @Autowired
    MyAuthenticationProvider myAuthenticationProvider;

    @Override
    protected void configure(AuthenticationManagerBuilder auth) throws Exception {
        auth.authenticationProvider(myAuthenticationProvider);
    }

    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http.addFilterBefore(new MyAuthenticationFilter(), BasicAuthenticationFilter.class)
                .authorizeRequests().antMatchers("/**")
                    .hasAnyRole()
                    .anyRequest()
                    .authenticated()
                    .and()
                .csrf().disable();
    }

    @Bean
    public ViewResolver viewResolver() {
        InternalResourceViewResolver viewResolver = new InternalResourceViewResolver();
        viewResolver.setPrefix("/WEB-INF/views/");
        viewResolver.setSuffix(".jsp");
        return viewResolver;
    }
}

• 我的验证提供者 *：

@Component
public class MyAuthenticationProvider implements AuthenticationProvider {
    @Override
    public Authentication authenticate(Authentication authentication) throws AuthenticationException {
        MyAuthenticationToken myAuthenticationToken = (MyAuthenticationToken) authentication;
        MyCredentials credentials = (MyCredentials) myAuthenticationToken.getCredentials();
        if (credentials.getPassword().equals("sesamOeffneDich") && credentials.getSecondSecret().equals(MyAuthenticationToken.SECOND_SECRET)) {
            myAuthenticationToken.setAuthenticated(true);
            return myAuthenticationToken;
        } else {
            throw new BadCredentialsException("Bad credentials supplied!");
        }
    }

    @Override
    public boolean supports(Class<?> authentication) {
        return MyAuthenticationToken.class.isAssignableFrom(authentication);
    }
}