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问题：

在Spring Boot中添加servlet筛选器时没有默认构造函数

侯英达
2023-03-14

我读了关于如何在Spring Boot中添加servlet过滤器的另一篇文章，但是当我试图遵循它在UiA中添加内部WebConfig类的例子时，我得到了一个No Default Constructor错误-plhd--0/>类文件。

我正在尝试这个，因为添加忽略（/api-url到应用程序的SecurityConfig类导致一条消息，声明/api-url有一个空过滤器列表。我想为/api-url添加一个servlet过滤器，这样它的过滤器列表就不再是空的了。

WebConfig内部类的代码是：

@Configuration
public class WebConfig {

    @Bean
    public FilterRegistrationBean shallowEtagHeaderFilter() {
        FilterRegistrationBean registration = new FilterRegistrationBean();
        registration.setFilter(new ShallowEtagHeaderFilter());
        registration.setDispatcherTypes(EnumSet.allOf(DispatcherType.class));
        registration.addUrlPatterns("/api-url");
        return registration;
    }
}

需要对下面的代码进行哪些特定更改，才能在不引发错误的情况下将servlet过滤器添加到/api url？

UIC应用程序的完整代码。java类是：

@SpringBootApplication
@Controller
public class UiApplication extends WebMvcConfigurerAdapter {

    @Configuration
    public class WebConfig {

        @Bean
        public FilterRegistrationBean shallowEtagHeaderFilter() {
            FilterRegistrationBean registration = new FilterRegistrationBean();
            registration.setFilter(new ShallowEtagHeaderFilter());
            registration.setDispatcherTypes(EnumSet.allOf(DispatcherType.class));
            registration.addUrlPatterns("/api-url");
            return registration;
        }
    }

    public static void main(String[] args) {
        SpringApplication.run(UiApplication.class, args);
    }

    @Bean
    public LocaleChangeInterceptor localeChangeInterceptor() {
        LocaleChangeInterceptor lci = new LocaleChangeInterceptor();
        lci.setParamName("lang");
        return lci;
    }

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(localeChangeInterceptor());
    }

    @Configuration
    @Order(SecurityProperties.ACCESS_OVERRIDE_ORDER)
    @EnableWebSecurity
    @EnableGlobalMethodSecurity(prePostEnabled = true)
    protected static class SecurityConfiguration extends WebSecurityConfigurerAdapter {

        @Override
        public void configure(WebSecurity webSecurity) throws Exception {
            webSecurity.ignoring().antMatchers("/api-url");
        }

        @Override
        protected void configure(HttpSecurity http) throws Exception {
            http
                .formLogin()
                .and()
                .httpBasic().and()
                .authorizeRequests()
                    .antMatchers("/").permitAll()
                    .antMatchers("/secure**").permitAll()
                    .anyRequest().authenticated();;
        }
    }
}

当我尝试启动Spring Bootjar时，错误的完整堆栈跟踪是：

2016-04-10 10:32:58.759 ERROR 5174 --- [           main] o.s.boot.SpringApplication               : Application startup failed

org.springframework.context.ApplicationContextException: Unable to start embedded container; nested exception is org.springframework.boot.context.embedded.EmbeddedServletContainerException: Unable to start embedded Tomcat
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.onRefresh(EmbeddedWebApplicationContext.java:133) ~[spring-boot-1.3.0.RELEASE.jar!/:1.3.0.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:531) ~[spring-context-4.2.3.RELEASE.jar!/:4.2.3.RELEASE]
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:118) ~[spring-boot-1.3.0.RELEASE.jar!/:1.3.0.RELEASE]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:752) [spring-boot-1.3.0.RELEASE.jar!/:1.3.0.RELEASE]
    at org.springframework.boot.SpringApplication.doRun(SpringApplication.java:347) [spring-boot-1.3.0.RELEASE.jar!/:1.3.0.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:295) [spring-boot-1.3.0.RELEASE.jar!/:1.3.0.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1112) [spring-boot-1.3.0.RELEASE.jar!/:1.3.0.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1101) [spring-boot-1.3.0.RELEASE.jar!/:1.3.0.RELEASE]
    at demo.UiApplication.main(UiApplication.java:193) [modular-0.0.1-SNAPSHOT.jar!/:0.0.1-SNAPSHOT]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_45]
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_45]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_45]
    at java.lang.reflect.Method.invoke(Method.java:497) ~[na:1.8.0_45]
    at org.springframework.boot.loader.MainMethodRunner.run(MainMethodRunner.java:53) [modular-0.0.1-SNAPSHOT.jar!/:0.0.1-SNAPSHOT]
    at java.lang.Thread.run(Thread.java:745) [na:1.8.0_45]
Caused by: org.springframework.boot.context.embedded.EmbeddedServletContainerException: Unable to start embedded Tomcat
    at org.springframework.boot.context.embedded.tomcat.TomcatEmbeddedServletContainer.initialize(TomcatEmbeddedServletContainer.java:99) ~[spring-boot-1.3.0.RELEASE.jar!/:1.3.0.RELEASE]
    at org.springframework.boot.context.embedded.tomcat.TomcatEmbeddedServletContainer.<init>(TomcatEmbeddedServletContainer.java:76) ~[spring-boot-1.3.0.RELEASE.jar!/:1.3.0.RELEASE]
    at org.springframework.boot.context.embedded.tomcat.TomcatEmbeddedServletContainerFactory.getTomcatEmbeddedServletContainer(TomcatEmbeddedServletContainerFactory.java:452) ~[spring-boot-1.3.0.RELEASE.jar!/:1.3.0.RELEASE]
    at org.springframework.boot.context.embedded.tomcat.TomcatEmbeddedServletContainerFactory.getEmbeddedServletContainer(TomcatEmbeddedServletContainerFactory.java:167) ~[spring-boot-1.3.0.RELEASE.jar!/:1.3.0.RELEASE]
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.createEmbeddedServletContainer(EmbeddedWebApplicationContext.java:158) ~[spring-boot-1.3.0.RELEASE.jar!/:1.3.0.RELEASE]
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.onRefresh(EmbeddedWebApplicationContext.java:130) ~[spring-boot-1.3.0.RELEASE.jar!/:1.3.0.RELEASE]
    ... 14 common frames omitted
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'demo.UiApplication$WebConfig': Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [demo.UiApplication$WebConfig$$EnhancerBySpringCGLIB$$f410234e]: No default constructor found; nested exception is java.lang.NoSuchMethodException: demo.UiApplication$WebConfig$$EnhancerBySpringCGLIB$$f410234e.<init>()
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1105) ~[spring-beans-4.2.3.RELEASE.jar!/:4.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1050) ~[spring-beans-4.2.3.RELEASE.jar!/:4.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:510) ~[spring-beans-4.2.3.RELEASE.jar!/:4.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482) ~[spring-beans-4.2.3.RELEASE.jar!/:4.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) ~[spring-beans-4.2.3.RELEASE.jar!/:4.2.3.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.2.3.RELEASE.jar!/:4.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) ~[spring-beans-4.2.3.RELEASE.jar!/:4.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) ~[spring-beans-4.2.3.RELEASE.jar!/:4.2.3.RELEASE]
    at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:368) ~[spring-beans-4.2.3.RELEASE.jar!/:4.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1123) ~[spring-beans-4.2.3.RELEASE.jar!/:4.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1018) ~[spring-beans-4.2.3.RELEASE.jar!/:4.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:510) ~[spring-beans-4.2.3.RELEASE.jar!/:4.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482) ~[spring-beans-4.2.3.RELEASE.jar!/:4.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) ~[spring-beans-4.2.3.RELEASE.jar!/:4.2.3.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.2.3.RELEASE.jar!/:4.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) ~[spring-beans-4.2.3.RELEASE.jar!/:4.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202) ~[spring-beans-4.2.3.RELEASE.jar!/:4.2.3.RELEASE]
    at org.springframework.boot.context.embedded.ServletContextInitializerBeans.getOrderedBeansOfType(ServletContextInitializerBeans.java:232) ~[spring-boot-1.3.0.RELEASE.jar!/:1.3.0.RELEASE]
    at org.springframework.boot.context.embedded.ServletContextInitializerBeans.getOrderedBeansOfType(ServletContextInitializerBeans.java:213) ~[spring-boot-1.3.0.RELEASE.jar!/:1.3.0.RELEASE]
    at org.springframework.boot.context.embedded.ServletContextInitializerBeans.addServletContextInitializerBeans(ServletContextInitializerBeans.java:89) ~[spring-boot-1.3.0.RELEASE.jar!/:1.3.0.RELEASE]
    at org.springframework.boot.context.embedded.ServletContextInitializerBeans.<init>(ServletContextInitializerBeans.java:77) ~[spring-boot-1.3.0.RELEASE.jar!/:1.3.0.RELEASE]
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.getServletContextInitializerBeans(EmbeddedWebApplicationContext.java:235) ~[spring-boot-1.3.0.RELEASE.jar!/:1.3.0.RELEASE]
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.selfInitialize(EmbeddedWebApplicationContext.java:222) ~[spring-boot-1.3.0.RELEASE.jar!/:1.3.0.RELEASE]
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.access$000(EmbeddedWebApplicationContext.java:85) ~[spring-boot-1.3.0.RELEASE.jar!/:1.3.0.RELEASE]
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext$1.onStartup(EmbeddedWebApplicationContext.java:207) ~[spring-boot-1.3.0.RELEASE.jar!/:1.3.0.RELEASE]
    at org.springframework.boot.context.embedded.tomcat.TomcatStarter.onStartup(TomcatStarter.java:55) ~[spring-boot-1.3.0.RELEASE.jar!/:1.3.0.RELEASE]
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5170) ~[tomcat-embed-core-8.0.28.jar!/:8.0.28]
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150) ~[tomcat-embed-core-8.0.28.jar!/:8.0.28]
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1408) ~[tomcat-embed-core-8.0.28.jar!/:8.0.28]
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1398) ~[tomcat-embed-core-8.0.28.jar!/:8.0.28]
    at java.util.concurrent.FutureTask.run(FutureTask.java:266) ~[na:1.8.0_45]
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) ~[na:1.8.0_45]
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) ~[na:1.8.0_45]
    ... 1 common frames omitted
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [demo.UiApplication$WebConfig$$EnhancerBySpringCGLIB$$f410234e]: No default constructor found; nested exception is java.lang.NoSuchMethodException: demo.UiApplication$WebConfig$$EnhancerBySpringCGLIB$$f410234e.<init>()
    at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:85) ~[spring-beans-4.2.3.RELEASE.jar!/:4.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1098) ~[spring-beans-4.2.3.RELEASE.jar!/:4.2.3.RELEASE]
    ... 33 common frames omitted
Caused by: java.lang.NoSuchMethodException: demo.UiApplication$WebConfig$$EnhancerBySpringCGLIB$$f410234e.<init>()
    at java.lang.Class.getConstructor0(Class.java:3082) ~[na:1.8.0_45]
    at java.lang.Class.getDeclaredConstructor(Class.java:2178) ~[na:1.8.0_45]
    at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:80) ~[spring-beans-4.2.3.RELEASE.jar!/:4.2.3.RELEASE]
    ... 34 common frames omitted

java.lang.reflect.InvocationTargetException
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at org.springframework.boot.loader.MainMethodRunner.run(MainMethodRunner.java:53)
    at java.lang.Thread.run(Thread.java:745)
Caused by: org.springframework.context.ApplicationContextException: Unable to start embedded container; nested exception is org.springframework.boot.context.embedded.EmbeddedServletContainerException: Unable to start embedded Tomcat
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.onRefresh(EmbeddedWebApplicationContext.java:133)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:531)
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:118)
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:752)
    at org.springframework.boot.SpringApplication.doRun(SpringApplication.java:347)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:295)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1112)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1101)
    at demo.UiApplication.main(UiApplication.java:193)
    ... 6 more
Caused by: org.springframework.boot.context.embedded.EmbeddedServletContainerException: Unable to start embedded Tomcat
    at org.springframework.boot.context.embedded.tomcat.TomcatEmbeddedServletContainer.initialize(TomcatEmbeddedServletContainer.java:99)
    at org.springframework.boot.context.embedded.tomcat.TomcatEmbeddedServletContainer.<init>(TomcatEmbeddedServletContainer.java:76)
    at org.springframework.boot.context.embedded.tomcat.TomcatEmbeddedServletContainerFactory.getTomcatEmbeddedServletContainer(TomcatEmbeddedServletContainerFactory.java:452)
    at org.springframework.boot.context.embedded.tomcat.TomcatEmbeddedServletContainerFactory.getEmbeddedServletContainer(TomcatEmbeddedServletContainerFactory.java:167)
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.createEmbeddedServletContainer(EmbeddedWebApplicationContext.java:158)
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.onRefresh(EmbeddedWebApplicationContext.java:130)
    ... 14 more
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'demo.UiApplication$WebConfig': Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [demo.UiApplication$WebConfig$$EnhancerBySpringCGLIB$$f410234e]: No default constructor found; nested exception is java.lang.NoSuchMethodException: demo.UiApplication$WebConfig$$EnhancerBySpringCGLIB$$f410234e.<init>()
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1105)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1050)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:510)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197)
    at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:368)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1123)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1018)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:510)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202)
    at org.springframework.boot.context.embedded.ServletContextInitializerBeans.getOrderedBeansOfType(ServletContextInitializerBeans.java:232)
    at org.springframework.boot.context.embedded.ServletContextInitializerBeans.getOrderedBeansOfType(ServletContextInitializerBeans.java:213)
    at org.springframework.boot.context.embedded.ServletContextInitializerBeans.addServletContextInitializerBeans(ServletContextInitializerBeans.java:89)
    at org.springframework.boot.context.embedded.ServletContextInitializerBeans.<init>(ServletContextInitializerBeans.java:77)
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.getServletContextInitializerBeans(EmbeddedWebApplicationContext.java:235)
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.selfInitialize(EmbeddedWebApplicationContext.java:222)
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.access$000(EmbeddedWebApplicationContext.java:85)
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext$1.onStartup(EmbeddedWebApplicationContext.java:207)
    at org.springframework.boot.context.embedded.tomcat.TomcatStarter.onStartup(TomcatStarter.java:55)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5170)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1408)
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1398)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    ... 1 more
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [demo.UiApplication$WebConfig$$EnhancerBySpringCGLIB$$f410234e]: No default constructor found; nested exception is java.lang.NoSuchMethodException: demo.UiApplication$WebConfig$$EnhancerBySpringCGLIB$$f410234e.<init>()
    at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:85)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1098)
    ... 33 more
Caused by: java.lang.NoSuchMethodException: demo.UiApplication$WebConfig$$EnhancerBySpringCGLIB$$f410234e.<init>()
    at java.lang.Class.getConstructor0(Class.java:3082)
    at java.lang.Class.getDeclaredConstructor(Class.java:2178)
    at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:80)
    ... 34 more
[root@localhost CustomLogin2]#

共有2个答案

梁泰
2023-03-14

请遵循下面两个问题，它们有相似的问题，

史蒂文的回答

以及Spring项目中的一个问题

鞠边浩
2023-03-14

将您的WebConfig类设置为静态：

@Configuration
public static class WebConfig { ... }

另外，不要将所有配置放在一个类中，尝试将它们放在单独的类中。

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