When creating a class in the default package, it writes this at the beginning. Yes, the question is stupid, but I have this problem for the first time, what should I do?

Question

Java

Multiple markers at this line
- The type java.lang.Object cannot be resolved. It is indirectly referenced from required .class files
- Must declare a named package because this compilation unit is associated to the named module
'clicker'

Answer 1

Don't create classes in default package