becker.xtras.marks
Interface IMarks

All Known Implementing Classes:

SampleMarks

public interface IMarks

An interface to model a "spreadsheet" recording student assignment marks.

Implementation Hints

• Start with a class that extends Object and implements IMarks. Get it to compile by including stubs for each method in the IMarks interface. (A stub contains just enough code to compile -- no more. If the method has a void return type, the method's body will not contain any code. If the method returns a string, then include return "dummy"; as the only line of code in the body. A method returning an array of strings could contain return new String[0];.)
• Write a main method as suggested in the becker.xtras.marks package documentation, and debug the program so it runs without errors (but doesn't do much).
• You will need three arrays: one to store student names, one to store assignment names, and one to store the marks. Make them big enough to store 3 students and 2 assignments. Put data in them. Fix the methods getAssignmentNames, getStudentNames, getMark, and setMark so they do the right thing. Test your program.
• Complete saveFile. Run the program to test it and use it to create a file with the data you put in the arrays manually. Complete openFile so that it reads the data from a file into the arrays.
• Write the code for addAssignment and addStudent. A complete solution will verify that the arrays have enough room for the new information, expanding the arrays as necessary.
• Create a new array of strings to store the names of the calculations you will perform for each assignment (e.g.: "Average", "Min", and "Max"). Return this array in getAssignmentCalculationNames. Write the method performAssignmentCalculation. It will typically have a structure like this:

  public int performAssignmentCalculation(String calcName, String assignmentName)
  {  if (calcName.equals("Average"))
     {  // call a method to calculate the average for the given assignment
     } else if (calcName.equals("Min"))
     {  // call a method to calculate the minimum mark for the given assignment
     } else ...
  }

  When your calculations for each assignment are working, get the calculations for each student working in the same way.

Author:

Byron Weber Becker

Method Summary

void	addAssignment(String name) Add a new assignment to the marks "spreadsheet."
void	addStudent(String name) Add a new student to the marks "spreadsheet."
String[]	getAssignmentCalculationNames() Get the names of the calculations provided for assignments.
String[]	getAssignmentNames() Get the names of all the assignments.
int	getMark(String studentName, String assignName) Get a mark for a particular student and assignment.
String[]	getStudentCalculationNames() Get the names of the calculations provided for students.
String[]	getStudentNames() Get the names of the students.
int	performAssignmentCalculation(String calcName, String assignName) Perform one of the calculations defined for assignments.
int	performStudentCalculation(String calcName, String studentName) Perform one of the calculations defined for students.
void	readFile(String fileName) Read the marks "spreadsheet" from a file.
void	setMark(String studentName, String assignName, int mark) Set the mark for a particular student and assignment
void	writeFile(String fileName) Write the marks "spreadsheet" to a file.

Method Detail

getMark

int getMark(String studentName,
            String assignName)

Get a mark for a particular student and assignment.

Parameters:

studentName - the name of the student

assignName - the name of the assignment

Returns:

the mark assigned to this student for this assignment

setMark

void setMark(String studentName,
             String assignName,
             int mark)

Set the mark for a particular student and assignment

Parameters:

studentName - the name of the student

assignName - the name of the assignment

mark - the mark to be assigned to this student for this assignment

getAssignmentNames

String[] getAssignmentNames()

Get the names of all the assignments.

Returns:

the names of all the assignments

getStudentNames

String[] getStudentNames()

Get the names of the students.

Returns:

the names of all the students.

addAssignment

void addAssignment(String name)

Add a new assignment to the marks "spreadsheet."

Parameters:

name - the name of the new assignment

addStudent

void addStudent(String name)

Add a new student to the marks "spreadsheet."

Parameters:

name - the name of the new student

getAssignmentCalculationNames

String[] getAssignmentCalculationNames()

Get the names of the calculations provided for assignments. For example, one might be "Average". Then calling performAssignmentCalculation("Average", 0) would return the average of all the marks for assignment 0.

Returns:

the names of all the calculations provided for assignments

getStudentCalculationNames

String[] getStudentCalculationNames()

Get the names of the calculations provided for students. For example, one might be "Average Best Four Assignments". Then calling performStudentCalculation("Average Best Four Assignments", 5) would (presumably) return the average of the best four marks for student 5.

Returns:

the names of all the calculations provided for students

performAssignmentCalculation

int performAssignmentCalculation(String calcName,
                                 String assignName)

Perform one of the calculations defined for assignments.

Parameters:

calcName - one of the names returned by getAssignmentCalculationNames()

assignName - the name of the assignment

Returns:

the result of the calculation

performStudentCalculation

int performStudentCalculation(String calcName,
                              String studentName)

Perform one of the calculations defined for students.

Parameters:

calcName - one of the names returned by getStudentCalculationNames()

studentName - the name of the student

Returns:

the result of the calculation

readFile

void readFile(String fileName)
              throws FileNotFoundException

Read the marks "spreadsheet" from a file.

Parameters:

fileName - the name of the file to read

Throws:

FileNotFoundException

writeFile

void writeFile(String fileName)
               throws FileNotFoundException

Write the marks "spreadsheet" to a file.

Parameters:

fileName - the name of the file

Throws:

FileNotFoundException