写了Controller类返回json数据文件时候报错
This application has no explicit mapping for /error, so you are seeing this as a fallback.
回到idear发现报错： Error querying database. Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Failed to obtain JDBC Connection; nested exception is java.sql.SQLException: Access denied for user ‘root’@‘localhost’ (using password: YES) The error may exist in edu/xalead/dao/ItemDao.java (best guess) The error may involve edu.xalead.dao.ItemDao.selectAll The error occurred while executing a query Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Failed to obtain JDBC Connection; nested exception is java.sql.SQLException: Access denied for user ‘root’@‘localhost’ (using password: YES)] with root cause java.sql.SQLException: Access denied for user ‘root’@‘localhost’ (using password: YES)
猜测应该是数据库连接的问题，去application.yaml文件下查看数据库连接。
spring: application: name: item-service datasource: url: jdbc:mysql://localhost:3306/路径不完整所以连接有问题
spring: application: name: item-service datasource: url: jdbc:mysql://localhost:3306/jdd补全你的数据库路径，结果还是发现同样的错误！
Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Failed to obtain JDBC Connection; nested exception is java.sql.SQLException: Access denied for user ‘root’@‘localhost’ (using password: YES)] with root cause java.sql.SQLException: Access denied for user ‘root’@‘localhost’ (using password: YES)
再看一遍，原来是数据库的用户名和密码的错误！ 这波啊，这波是一石二鸟…
datasource: url: jdbc:mysql://localhost:3306/jdd username: root password:把自己的数据库密码和用户名校正就好了！
最后在刷新一下网页，返回的数据与数据库中的数据匹配即成功。
