Eclipse上的Java包名称编译问题

Question

I have an issue on Eclipse regarding compiling with a Java package name (TurtleGraphics). This is my code:

package TurtleGraphics;

import TurtleGraphics.KeyboardReader;

public class Loops21 {

    public static void main(String[] args) {
        // Navo

        int count = 1, sum = 0;
        KeyboardReader reader = new KeyboardReader();
        while(count<=50)
        {
            sum = sum + count;
            System.out.println(count + "\t" + sum );
            count++;
        }

    }

}

The problem is that it has not been recognizing KeyboardReader. I have always been using this but all of a sudden I have a problem. This is what it says:

Exception in thread "main" java.lang.Error: Unresolved compilation problem: The declared package "TurtleGraphics" does not match the expected package ""
    at KeyboardReader.<init>(KeyboardReader.java:5)
    at Loops21.main(Loops21.java:9)

Thank you for all the help. I have a solution which is reinstalling Eclipse, but I don't know if that will work.

Answer 1

Assuming your source file Loops21.java starts with:

package TurtleGraphics;

import TurtleGraphics.KeyboardReader;

public class Loops21 {

And the file KeyboardReader.java starts with:

package TurtleGraphics;

Then the following worked for me:

> mkdir TurtleGraphics
> mv KeyboardReader.java TurtleGraphics
> mv Loops21.java TurtleGraphics
> javac TurtleGraphics/Loops21.java 
> java TurtleGraphics/Loops21
1   1
2   3
3   6
...
48  1176
49  1225
50  1275
> 

The dot in the import path name represents directory structure so you need to build that directory structure. The above is a command line example, you need to do the Eclipse equivalent.