如何在SpringBoot中获取所有@RestController注解类的列表？

方法一：通过ApplicationContext获取已实例化的@RestController Bean #

Spring容器的ApplicationContext提供了getBeansWithAnnotation方法，可以直接检索所有被容器管理、带有指定注解的Bean实例，无论这些Bean来自自定义代码还是第三方库。

import org.springframework.context.ApplicationContext;
import org.springframework.stereotype.Component;
import org.springframework.web.bind.annotation.RestController;
import javax.annotation.PostConstruct;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

@Component
public class RestControllerCollector {

    private final ApplicationContext applicationContext;
    private List<Object> allRestControllers;

    public RestControllerCollector(ApplicationContext applicationContext) {
        this.applicationContext = applicationContext;
    }

    @PostConstruct
    public void collectRestControllers() {
        // 获取所有标注了@RestController的Bean，key为Bean名称，value为实例
        Map<String, Object> restControllerBeans = applicationContext.getBeansWithAnnotation(RestController.class);
        allRestControllers = restControllerBeans.values().stream().collect(Collectors.toList());
        
        // 可添加验证逻辑，比如打印所有控制器类名
        allRestControllers.forEach(bean -> System.out.println("检测到RestController：" + bean.getClass().getName()));
    }

    public List<Object> getAllRestControllers() {
        return allRestControllers;
    }
}

使用时，直接注入RestControllerCollector调用getAllRestControllers方法即可获取所有控制器实例列表。

方法二：通过BeanDefinitionRegistryPostProcessor获取控制器类信息（无需实例） #

如果只需要获取@RestController标注的类对象而非实例，可以在Bean实例化前通过BeanDefinitionRegistryPostProcessor扫描所有Bean定义：

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.beans.factory.support.BeanDefinitionRegistry;
import org.springframework.beans.factory.support.BeanDefinitionRegistryPostProcessor;
import org.springframework.core.type.AnnotationMetadata;
import org.springframework.stereotype.Component;
import org.springframework.web.bind.annotation.RestController;
import java.util.ArrayList;
import java.util.List;

@Component
public class RestControllerClassCollector implements BeanDefinitionRegistryPostProcessor {

    private List<Class<?>> restControllerClasses = new ArrayList<>();

    @Override
    public void postProcessBeanDefinitionRegistry(BeanDefinitionRegistry registry) throws BeansException {
        String[] beanNames = registry.getBeanDefinitionNames();
        for (String beanName : beanNames) {
            BeanDefinition definition = registry.getBeanDefinition(beanName);
            AnnotationMetadata metadata = definition.getMetadata();
            
            // 检查当前Bean定义是否标注了@RestController
            if (metadata.hasAnnotation(RestController.class.getName())) {
                try {
                    Class<?> clazz = Class.forName(metadata.getClassName());
                    restControllerClasses.add(clazz);
                } catch (ClassNotFoundException e) {
                    e.printStackTrace();
                }
            }
        }
        
        // 验证输出
        restControllerClasses.forEach(clazz -> System.out.println("检测到RestController类：" + clazz.getName()));
    }

    @Override
    public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
        // 无需额外处理
    }

    public List<Class<?>> getRestControllerClasses() {
        return restControllerClasses;
    }
}

关键注意事项 #

1. 确保第三方控制器被Spring扫描：如果第三方库的@RestController未被自动扫描，需要在启动类中手动指定扫描包路径：

@SpringBootApplication(scanBasePackages = {"com.your.custom.package", "com.thirdparty.controller.package"})
public class YourApplication {
    public static void main(String[] args) {
        SpringApplication.run(YourApplication.class, args);
    }
}

2. 第三方自动配置类的兼容性：如果第三方库通过自动配置类注册控制器，上述两种方法依然有效，因为Bean定义会被正常注册到Spring容器中。

内容的提问来源于stack exchange，提问作者PatPanda