Re: Global enums and constants

From:
Patricia Shanahan <pats@acm.org>
Newsgroups:
comp.lang.java.help
Date:
Tue, 14 Feb 2012 15:24:48 -0800
Message-ID:
<GrmdnVmFvuvMcKfSnZ2dnUVZ_u-dnZ2d@earthlink.com>
Davej wrote:

On Feb 14, 4:53 pm, Daniel Pitts
<newsgroup.nos...@virtualinfinity.net> wrote:

On 2/14/12 2:37 PM, Davej wrote:

I'm having trouble accessing constants. I know it is always best to
define a constant in only one place, but public or private I still
can't see it. What am I doing wrong? Thanks.

The problem is on line 15 of the example you posted.

In other words, we don't know what you've tried, what error messages you
see, or what you are really attempting to do. Please provide an SSCCE
<http://sscce.org/> and then we'll be able to help without the use of
clairvoyance.


Well, I had a constant CLASSFILEPATH defined here...
__________________________________________________
package servlets;

import business.FileIO;
import business.Student;
import java.io.IOException;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class CalculateGradesServlet extends HttpServlet {
    private String msg;
    //private final String CLASSFILEPATH = "/WEB-INF/ClassList.txt";
[etc...]
___________________________________________________

And I thought it should be moved somewhere else so I put it here...
___________________________________________________
package business;

import java.util.Arrays;

public class Student {
    private enum CALC {NONE, QUIZ, COURSE, LETTER};
    public final String CLASSFILEPATH = "/WEB-INF/ClassList.txt";
[etc...]
 ___________________________________________________

Now note that the first file has an import for the second file. Still
the
constant cannot be seen inside the servlets package. The error is;

error: cannot find symbol
  String path = sc.getRealPath(CLASSFILEPATH);
  symbol: variable CLASSFILEPATH
  location: class CalculateGradesServlet
1 error


You need to reference it as Student.CLASSFILEPATH. Or use import static.

Patricia

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