Mine

public static void main(String[] args) throws Exception{
    	final double NUMBER_OF_GRADES = 5.0;
        String line = "";
        String firstname = "";
        String lastname = "";
        double sum = 0;
        
        File fileName = new File("grades2.txt"); 
  
        BufferedReader fileIn = new BufferedReader(new FileReader(fileName));
        
        while (( line = fileIn.readLine()) != null){         
        	if( !line.trim().equals("")) {
        		String[] student = line.split( " " );
        		firstname = student[0];
        		lastname = student[1];
        		for( int i = 2; i < student.length; i++ ) {
        			sum = sum + Integer.valueOf( student[i] );
        		}
        		double average = sum/NUMBER_OF_GRADES;
        		char grade;
        		if( average >= 90 ) {
        			grade = 'A';
        		}else{
        			if( average >= 80 ) {
        				grade = 'B';
        			}else{
        				if( average >= 70 ) {
        					grade = 'C';
        				}else{
        					if( average >= 60 ) {
        						grade = 'D';
        					}else{
        						grade = 'F';
        					}
        				}
        			}
        		}
        		System.out.println( firstname + " " + lastname + " " + average + " " + grade );
        		sum = 0;
        	}
        }
            
    }