后端开发常见错误

错误1：Request method ‘DELETE‘ not supported

• 错误还原：controller层有一个接口，访问该接口时报错：Request method ‘DELETE‘ not supported
  
• 错误原因：没有接收到前端传入的参数，修改为如下
  
• [参考]( https://blog.csdn.net/weixin_47211345/article/details/117637529#:~:text=Request method ‘DELETE’ not ,supported%E8%BF%99%E4%B8%AA%E6%8A%A5%E9%94%99%E9%81%87%E5%88%B0%E8%BF%87%E5%A5%BD%E5%87%A0%E6%AC%A1%EF%BC%8C%E7%84%B6%E5%90%8E%E6%95%B4%E7%90%86%E5%87%BA%E4%B8%89%E4%B8%AA%E5%8E%9F%E5%9B%A0%EF%BC%88%E5%8F%AF%E8%83%BD%E6%9C%89%E5%85%B6%E4%BB%96%E7%9A%84%E5%8E%9F%E5%9B%A0%E5%90%A7%EF%BC%8C%E5%8F%AA%E6%98%AF%E6%88%91%E7%9B%AE%E5%89%8D%E9%81%87%E5%88%B0%E7%9A%84%E9%83%BD%E6%98%AF%E8%BF%99%E4%B8%89%E7%A7%8D%EF%BC%89%E7%AC%AC%E4%B8%80%E7%A7%8D%E6%98%AFservice%E5%B1%82%E7%9A%84%E5%AE%9E%E7%8E%B0%E7%B1%BB%E6%B2%A1%E6%9C%89return%E8%BF%99%E4%B8%AA%E6%96%B9%E6%B3%95%E8%BF%99%E7%A7%8D%E9%94%99%E8%AF%AF%E5%9C%A8%E5%90%AF%E5%8A%A8%E6%9C%8D%E5%8A%A1%E6%97%B6%E6%98%AF%E7%9C%8B%E4%B8%8D%E5%87%BA%E6%9D%A5%E9%97%AE%E9%A2%98%E7%9A%84%EF%BC%8C%E6%B2%A1%E6%9C%89%E6%8A%A5%E9%94%99%E4%BF%A1%E6%81%AF%E9%BB%98%E8%AE%A4%E6%98%AFnull%EF%BC%8C%E6%89%80%E4%BB%A5%E4%BC%9A%E6%9C%89%E5%8F%AF%E8%83%BD%E7%96%8F%E6%BC%8F%E4%BA%86%E5%BF%98%E4%BA%86%E5%86%99%E7%AC%AC%E4%BA%8C%E7%A7%8D%E6%98%AF%E5%9C%A8%E6%8E%A5%E5%8F%A3%E8%B7%AF%E5%BE%84%E4%B8%AD%E6%B2%A1%E6%9C%89%E5%8A%A0%E4%B8%8A%20%2F%20%7B%20id%20%7D%E8%BF%99%E4%B8%AA%E4%B9%9F%E6%98%AF%E6%AF%94%E8%BE%83%E5%A5%BD%E6%89%BE%E7%9A%84%E6%8A%A5%E9%94%99%E7%AC%AC%E4%B8%89%E7%A7%8D%E6%98%AFMapper%E6%96%87%E4%BB%B6%E7%9A%84%E5%8A%A8%E6%80%81SQL%E8%AF%AD%E5%8F%A5%E5%87%BA%E9%97%AE%E9%A2%98Mapper%E6%96%87%E4%BB%B6%E6%8A%A5%E9%94%99%E6%98%AF%E5%AF%B9%E6%95%B0%E6%8D%AE%E5%BA%93%E4%BA%86%E8%A7%A3%E4%B8%8D%E6%B7%B1%E7%9A%84%E4%BA%BA%E8%80%8C%E8%A8%80%E5%BE%88%E5%AE%B9%E6%98%93%E5%87%BA%E7%8E%B0%E7%9A%84%E6%8A%A5%E9%94%99%EF%BC%8C%E5%AD%97)

错误2：cannot resolve symbol 'log'

• 错误还原：使用log.info();时报错cannot resolve symbol 'log'
• 错误原因：idea没有安装Lombok插件、项目没有导入Lombok依赖、类中没有添加注解@Slf4j

错误3：bean注入失败

• 错误描述：当某个bean注入到另一个类中时，IDE提示没有注入
• 解决方案：在IDEA中 点击 File → Invalidate Caches/Restart，清理了缓存重启IDEA
• 参考

错误4：乱码，设置编码格式

• 错误还原：启动项目后控制台打印：org.yaml.snakeyaml.error.YAMLException: java.nio.charset.MalformedInputException: Input length = 1
• 解决方案：将IDE的编码格式改为UTF-8
• 参考

错误5：乱码

• gradle项目打包时报错
  
• 解决方案：删除报错字符

错误6：外部配置文件，配置冲突

• 在cloudalibaba + security项目中配置nacos报错：org.springframework.beans.factory.BeanCreationException: Error creating bean with name
• 解决方案：注释掉management

spring:
  cloud:
    nacos:
      discovery:
        server-addr: 192.168.43.150:8848 
management:
  endpoints:
    web:
      exposure:
        include: '*'