average1.java

User interface java program which calculates average of marks

//average of grades for whole class with wrongly inserted marks detection
// @author mohammed teeti
//id: 1200821106

   import javax.swing.JOptionPane;
   import java.text.*;

   public class Average1 {

      public static void main( String args[] )
      {
        int i;
        double total=0;
        double grade=0;          
        double average;
        int numberOfStudents;
        String element,GradeLevel,CourseName;
        
        element = JOptionPane.showInputDialog("Insert the number of students in class");
        numberOfStudents= Integer.parseInt(element);
        element = JOptionPane.showInputDialog("Insert the name of course");
        CourseName=element;

        // reading course name, number of student and marks
       for(i=1;i<= numberOfStudents;i++)
       {
        element = JOptionPane.showInputDialog(null,"Enter the mark of student #"+":"+i,CourseName, JOptionPane.INFORMATION_MESSAGE);
        grade = Double.valueOf(element);
        if(grade<=100 && grade >=0)
        { total =total+grade;} else {--i;}

       }
//calculate average for the whole class grade
        average=total / numberOfStudents  ;
        

        //assigning mark letter/level
        if(90<=average && average<=100){GradeLevel="A";}
        else if(70<=average && average<90){GradeLevel="B";}
        else if(60<=average && average<70){GradeLevel="C";}
        else {GradeLevel="D";}

         // display average of exam grades and Grade level
        DecimalFormat twoDigits=new DecimalFormat("00.0");
         JOptionPane.showMessageDialog( null,"Class average is " + twoDigits.format(average)+ "\n"
                 +"Avergae Level is :"+GradeLevel, CourseName+":"+"course grade average ", JOptionPane.INFORMATION_MESSAGE );

      System.exit( 0 );  // terminate the program

      } // end main
  } // end class Average1