Cannot find symbol error when importing enum class

Question

So I'm facing a cannot find symbol error when static importing an enum in a class that depends on it. They are both in separate files within the same directory. I've omitted an explicit package name.

TokenType.java

// No imports
enum TokenType {
  
  ADD, MINUS, MULTIPLY, DIVIDE,
  ...

}

Scanner.java

import java.util.ArrayList;
import java.util.List;
import java.util.HashMap;
import java.util.Map;

import static TokenType.*; // <--- (error: cannot find symbol)

class Scanner {
  
  private static final Map <String, TokenType> keywords; // <--- (no error; javac can resolve the class name just fine)

  static {
    keywords = new HashMap<>();
    keywords.put("+", ADD); // <-- (error: cannot find symbol, which makes sense)
    keywords.put("-", MINUS);
    ...
  }
  ...
}

I'm just not sure how to proceed. The names are all typed correctly, and there is only one TokenType class so there isn't a class conflict. My other classes in the project directory have no nested classes, do not extend/implement from other classes, or import libraries that have a TokenType class in their dependencies. I've cleaned my directory of all stale classes before each compile, and even changed the order in which I'm calling javac. Any help would be wonderful, thank you.

EDIT: Solution was to put them in a named package. Java doesn't allow imports from default package.

*"I've omitted an explicit package name"*. You should replace it with something other, but similar and not just omit it. Just omitting it isn't helpful for questions like this here. — Tom, Jun 26 '21 at 00:01

score 2 · Accepted Answer · answered Jun 26 '21 at 01:15

From the fact that the compiler can resolve the simple name TokenType in Map <String, TokenType>, it seems like TokenType is declared in the same package as Scanner.

You also said that you "omitted an explicit package name", which implies that both of these classes are not declared in the default package (static imports are not possible if they are in the default package), but some package with a name. Let's suppose that both of them are in

package com.example.foo;

Then you need to do:

import static com.example.foo.TokenType.*;

Note that even if you are in a location where the type is accessible with its simple name, you still need to use its canonical name (basically with the package name fully written out) in a static import declaration., and the name has to be qualified (in the form of X.Y), which is why classes in the default package don't work.

Thank you! Wish I could upvote your answer. Putting my project in a named package was the solution; it seems Java forbids any kind of import from the default package. For future readers, this link contains a lot of information on import rules/standards. https://www.mindprod.com/jgloss/import.html — justin, Jun 28 '21 at 20:26

Cannot find symbol error when importing enum class

1 Answers1