First you should check how you declare readFile and errorFile:
  PreReadError readfile;
  String errorfile;

"errorFile" is a String object (readFile is the PreReadError object) and you
are trying to use a PreReadError method on a String.
str=(String )errorfile.getTable("Error0");

I presume that you mean:
str=(String )readfile.getTable("Error0");

Hope this helps.
-----Original Message-----
From: Edward [mailto:zhangsc@n...]
Sent: 29 May 2002 07:20
To: Servlets
Subject: [servlets] How to create and call context in servlet?
Importance: High

   I have a Hash table,I want to place it into context of a servlet,so this
Hash table can be called by any users.My Hash table file named
"PreReadError.java",it is follows:
 public class PreReadError
{
   public PreReadError()
  {
     Hashtable table=new Hashtable();
      table.put("Error0","Error");
      table.put("Error1","Redirect");
  }

  public String getTable(String str)
 {
  String result=(String) table.get(str);
  return result;
 }
}


My servlet file named "GetUserIdentity.java" is follows:

import javax.servlet.ServletContext;
public class GetUserIdentity extends HttpServlet
{
  PreReadError readfile;
  String errorfile;
  String str;
  ServletContext context;

  public GetUserIdentity()
 {
    context=getServletContext();
 }

 public void doPost(HttpServletRequest request,HttpServletResponse response)
     throws ServletException,IOException
 {
    //Here,I want to create a context if it is not exist,else call it's
method directly
    if(context.getAttribute("errorfile")==null)
    {
       readfile=new PreReadError();
       context.setAttribute(errorfile,readfile);
    }
    str=(String )errorfile.getTable("Error0");
    System.out.println("Message is:"+str);
  }
 }
}

When I compile it,it raise a error,it follows:

F:\login\ejb>javac -classpath .;f:\j2sdkee1.3.1\lib\j2ee.jar
GetUserIdentity.java

GetUserIdentity.java:55: cannot resolve symbol
symbol  : method getTable  (java.lang.String)
location: class java.lang.String
                        str=(String )errorfile.getTable("Error0");
                                              ^
1 error

I don't know how to put my Hashtable into a servlet and how to call it's
methods?
Any idea will be appreciated!
Thanks in advance.
Edward