Spring错误-kob-Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exc

Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is java.lang.NullPointerException] with root cause

看了数据库id 不为null，主键等都设置了

没加

@Autowired@Autowired注释：它可以对类成员变量、方法及构造函数进行标注，完成自动装配的工作。==>自动注入依赖的Bean。一个AutoWired只能接管一个bean

错误

*******每一个声明都要一个@Autowired

太开心了

@Autowired//注入数据库
private UserMapper userMapper;
@Autowired
private PasswordEncoder passwordEncoder;

参考

报错解决：Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception-CSDN博客