Spring Boot 使用 springfox-boot-starter 接入 Swagger2

添加依赖

<dependency>
    <groupId>io.springfox</groupId>
    <artifactId>springfox-boot-starter</artifactId>
    <version>3.0.0</version>
</dependency>

可能出现的错误

org.springframework.context.ApplicationContextException: Failed to start bean 'documentationPluginsBootstrapper'; nested exception is java.lang.NullPointerException
    at org.springframework.context.support.DefaultLifecycleProcessor.doStart(DefaultLifecycleProcessor.java:181) ~[spring-context-5.3.19.jar:5.3.19]
    at org.springframework.context.support.DefaultLifecycleProcessor.access$200(DefaultLifecycleProcessor.java:54) ~[spring-context-5.3.19.jar:5.3.19]
    at org.springframework.context.support.DefaultLifecycleProcessor$LifecycleGroup.start(DefaultLifecycleProcessor.java:356) ~[spring-context-5.3.19.jar:5.3.19]
    at java.base/java.lang.Iterable.forEach(Iterable.java:75) ~[na:na]
    at org.springframework.context.support.DefaultLifecycleProcessor.startBeans(DefaultLifecycleProcessor.java:155) ~[spring-context-5.3.19.jar:5.3.19]
    at org.springframework.context.support.DefaultLifecycleProcessor.onRefresh(DefaultLifecycleProcessor.java:123) ~[spring-context-5.3.19.jar:5.3.19]
    at org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:935) ~[spring-context-5.3.19.jar:5.3.19]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:586) ~[spring-context-5.3.19.jar:5.3.19]
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:145) ~[spring-boot-2.6.7.jar:2.6.7]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:740) ~[spring-boot-2.6.7.jar:2.6.7]
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:415) ~[spring-boot-2.6.7.jar:2.6.7]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:303) ~[spring-boot-2.6.7.jar:2.6.7]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1312) ~[spring-boot-2.6.7.jar:2.6.7]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1301) ~[spring-boot-2.6.7.jar:2.6.7]
    at com.example.learnswagger2.LearnSwagger2Application.main(LearnSwagger2Application.java:11) ~[classes/:na]

原因

版本限制：Spring Boot 2.6.0后会出现问题，具体可参考如下链接：

https://github.com/springfox/springfox/issues/3462

解决方法一

添加@EnableWebMvc注解。

import org.springframework.web.servlet.config.annotation.EnableWebMvc;

@EnableWebMvc
@SpringBootApplication
public class LearnSwagger2Application {

    public static void main(String[] args) {
        SpringApplication.run(LearnSwagger2Application.class, args);
    }

}

解决方法二

配置文件中增加如下配置。

spring:
  mvc:
    pathmatch:
      matching-strategy: ant_path_matcher

访问地址

Spring Boot监听了8080端口。

http://localhost:8080/swagger-ui/index.html

http://localhost:8080/v2/api-docs

生产环境关闭

springfox:
  documentation:
    enabled: false

备注

springfox已迁移到springdoc。

GitHub

https://github.com/springfox/springfox