Errors in my third Java assignment

This is my third Java assignment for my class and i'm already having lots of trouble..It's kind of frustrating, especially since I know I have a loong way to go and this should be pretty basic. I guess patience is a virtue though:o

I have two java files that have to be slightly modified. What they want is this...

1) Include a String instance variable that represents the name of the course's instructor

2) Provide a set method to change the instructor's name and a get method to retrieve it.

3) Modify the constructor to specify two parameters--one for the course name and one for the instructor's name.

4) Modify method displayMessage to output the welcome message and course name, followed by "This course is presented by:" and the instructors name.

Here is what I have so far---(first file--Gradebook)

I included the lines where it says I have errors.

Code:

---

public class GradeBook
{
        private String courseName; // course name for this GradeBook
        private String instructorName; // instructor's name for this Gradebook
       
        // constructor initializes courseName and
        // instructor name with String argument
        public GradeBook ( String courseName, String instructorName)
        {
**ln13**                courseName = name;
**ln14**                instructorName = name;
        } // end constructor
       
        //method to set the course name
        public void setcourseName ( String name )
        {
                courseName = name; // store the course name
        } // end method setCourseName
       
        // method to retrieve the course name
        public String getcourseName()
        {
                return courseName;
        } // end method getCourseName
       
        //method to set the instructor name
        public void setInstructorName ( String name )
        {
**ln32**                InstructorName = name; // store the instructor name
        } // end method setInstructorName
       
        // method to retrieve the instructor name
        public String getInstructorName()
        {
                return instructorName;
        } // end method getIntructorName
       
        //display a welcome message to the GradeBook User
        public void displayMessage()
        {
                // this statement calls getCourseName to get the
                // name of the course this GradeBook represents
                System.out.printf ( "Welcome to the Grade Book for\n%s!\n",
                        getcourseName());
        } // end method displayMessage
}//end class GradeBook

---

and the second file--(GradeBookTest)

Code:

---

public class GradeBookTest
{
        //main method begins program execution
        public static void main ( String [] args )
        {
                // create GradeBook Object
                GradeBook gradeBook1 = new GradeBook(
                        "CS101 Introduction to Java Programming" , "Hank Hill" );
                GradeBook gradeBook2 = new GradeBook(
                        "CS102 Data Structures in Java", "Dale Gribble" );
                       
                // display initial value of courseName for each Gradebook
                System.out.printf( "gradeBook1 course name is: %s\n",
**ln18**                        gradeBook1.getCourseName() );
                System.out.printf( "gradeBook2 course name is: %s\n",
**ln20**                        gradeBook2.getCourseName() );
               
                System.out.printf( "This course is presented by: %s\n",
**ln23**                        gradebook1.getInstructorName() );
                System.out.printf( "This course is presented by: %s\n",
**ln25**                        gradebook2.getInstructorName() );

        } // end main
} // end class GradeBookTest

---

This what the errors say when I run it in the command prompt.

Code:

---

C:\Examples\ch03\fig03_10_11>javac *.java
GradeBook.java:13: cannot find symbol
symbol  : variable name
location: class GradeBook
                courseName = name;
                            ^
GradeBook.java:14: cannot find symbol
symbol  : variable name
location: class GradeBook
                instructorName = name;
                                ^
GradeBook.java:32: cannot find symbol
symbol  : variable InstructorName
location: class GradeBook
                InstructorName = name; // store the instructor name
                ^
GradeBookTest.java:18: cannot find symbol
symbol  : method getCourseName()
location: class GradeBook
                        gradeBook1.getCourseName() );
                                  ^
GradeBookTest.java:20: cannot find symbol
symbol  : method getCourseName()
location: class GradeBook
                        gradeBook2.getCourseName() );
                                  ^
GradeBookTest.java:23: cannot find symbol
symbol  : variable gradebook1
location: class GradeBookTest
                        gradebook1.getInstructorName() );
                        ^
GradeBookTest.java:25: cannot find symbol
symbol  : variable gradebook2
location: class GradeBookTest
                        gradebook2.getInstructorName() );
                        ^
7 errors

---

If someone could push me in the right direction, that would be much appreciated.

Here:

Code:

---

        public GradeBook ( String courseName, String instructorName)
        {
**ln13**                courseName = name;
**ln14**                instructorName = name;
        }

---

There is no variable or parameter called "name" and so the compiler complains. You need to use the variable and parameter names that are present rather than make them up. For instance for the first line, you'd do:

Code:

---

        public GradeBook ( String courseName, String instructorName)
        {
                this.courseName = courseName;
                //...
        }

---

Where the this.courseName on the left of the assignment stands for the field of the class, and the courseName on the right of the assignment represents the parameter passed into the method. You want to set the guy on the left with the value passed into the guy on the right.

OK- I made the following changes, but i'm still having issues. Am I not declaring my variables correctly or what?

Code:

---

public class GradeBook
{
        private String courseName; // course name for this GradeBook
        private String instructorName; // instructor's name for this Gradebook
       
        // constructor initializes courseName and
        // instructor name with String argument
        public GradeBook ( String name, String instructor)
        {
                courseName = name;
                instructorName = instructor;
        } // end constructor
       
        //method to set the course name
        public void setcourseName ( String name )
        {
                courseName = name; // store the course name
        } // end method setCourseName
       
        // method to retrieve the course name
        public String getcourseName()
        {
                return courseName;
        } // end method getCourseName
       
        //method to set the instructor name
        public void setInstructorName ( String instructor )
        {
                InstructorName = Instructor; // store the instructor name
        } // end method setInstructorName
       
        // method to retrieve the instructor name
        public String getInstructorName()
        {
                return instructorName;
        } // end method getIntructorName
       
        //display a welcome message to the GradeBook User
        public void displayMessage()
        {
                // this statement calls getCourseName to get the
                // name of the course this GradeBook represents
                System.out.printf ( "Welcome to the Grade Book for\n%s!\n",
                        getcourseName());
        } // end method displayMessage
}//end class GradeBook

---

Second file

Code:

---

public class GradeBookTest
{
        //main method begins program execution
        public static void main ( String [] args )
        {
                // create GradeBook Object
                GradeBook gradeBook1 = new GradeBook(
                        "CS101 Introduction to Java Programming" , "Hank Hill" );
                GradeBook gradeBook2 = new GradeBook(
                        "CS102 Data Structures in Java", "Dale Gribble" );
                       
                // display initial value of courseName for each Gradebook
                System.out.printf( "gradeBook1 course name is: %s\n",
                        gradeBook1.getCourseName() );
                System.out.printf( "gradeBook2 course name is: %s\n",
                        gradeBook2.getCourseName() );
               
                System.out.printf( "This course is presented by: %s\n",
                        gradebook1.getinstructorName() );
                System.out.printf( "This course is presented by: %s\n",
                        gradebook2.getInstructorName() );

        } // end main
} // end class GradeBookTest

---

Error report---

Code:

---

C:\Examples\ch03\fig03_10_11>javac *.java
GradeBook.java:32: cannot find symbol
symbol  : variable InstructorName
location: class GradeBook
                InstructorName = Instructor; // store the instructor name
                ^
GradeBook.java:32: cannot find symbol
symbol  : variable Instructor
location: class GradeBook
                InstructorName = Instructor; // store the instructor name
                                ^
GradeBookTest.java:18: cannot find symbol
symbol  : method getCourseName()
location: class GradeBook
                        gradeBook1.getCourseName() );
                                  ^
GradeBookTest.java:20: cannot find symbol
symbol  : method getCourseName()
location: class GradeBook
                        gradeBook2.getCourseName() );
                                  ^
GradeBookTest.java:23: cannot find symbol
symbol  : variable gradebook1
location: class GradeBookTest
                        gradebook1.getinstructorName() );
                        ^
GradeBookTest.java:25: cannot find symbol
symbol  : variable gradebook2
location: class GradeBookTest
                        gradebook2.getInstructorName() );
                        ^
6 errors

---

Code:

---

GradeBook.java:32: cannot find symbol
symbol  : variable InstructorName
location: class GradeBook
                InstructorName = Instructor; // store the instructor name

---

Follow Java naming conventions and start variables (and methods) with a lowercase letter. In part this will solve problems like this one.

Another convention is to use camelCase when you have variables and methods made up of multiple words like getCourseName(). You have a choice with something like "gradebook": but make that choice and then stick to it. The compiler will complain about the smallest typo so you have to be absolutely consistent in how you spell things.

Awesome, I got it working. Thank you so much guys. What a good feeling this is:D

I think I found a new favorite forum, lol;)

You're welcome.