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Hi.. Im experiencing a weird error I dont know how to fix. I have a scanner object and whenever I use nextInt, anything above 3 causes the program to crash saying and links me to this line of the class: (one I added all the asteriss to.
// If we are at the end of input then NoSuchElement;
// If there is still input left then InputMismatch
private void throwFor() {
skipped = false;
if ((sourceClosed) && (position == buf.limit()))
throw new NoSuchElementException(); ****************
else
throw new InputMismatchException();
}
My code is also below. Please ignore the Class for the student objects and assume all is working there.
import java.util.*;
import java.lang.*;
/*----------------------------------------------------------------------------*/
public class StudentGrade
{
final static int STUD_MAX = 100;
final static int MAX_INT = Integer.MAX_VALUE;
private static int studCount = -1;
private static Scanner keyBd = new Scanner(System.in);
public static void main(String [] args)
{
int option = 0;
double av = 0.0;
boolean func = false;
studentInfo();
Student[] Students = new Student[STUD_MAX];
for(int index = 0; index < STUD_MAX; index++)
{
Students[index] = new Student(0);
}
do
{
option = dispMenu();
switch (option)
{
case 1:
System.out.println("Program Exiting...");
break;
case 2:
func = true;
createNewStud(Students, func);
break;
case 3:
printAll(Students);
break;
case 4:
av = calcAvMark(Students);
break;
case 5:
av = calcAvMark(Students);
dispDivMarks(Students, av);
break;
case 6:
dispDistGrades(Students);
break;
case 7:
findByStudNum(Students);
break;
case 8:
findByStudName(Students);
break;
case 9:
func = false;
createNewStud(Students, func);
break;
case 10:
checkTopGrades(Students);
break;
case 11:
sortStudsNum(Students);
break;
case 12:
sortStudsAlpha(Students);
break;
default:
System.out.println("Incorrect input. Try again.");
}
}while(option != 1);
return;
}
/*------------------------------------------------------------------------*/
public static void studentInfo()
{
System.out.println("Name: N/A.");
System.out.println("Student Number: N/A.");
System.out.println("Enrolment mode: Internal.");
System.out.println("Tutorial Day: Tuesday.");
System.out.println("Time: 4:30pm.");
System.out.println("Tutor: Dr Piara Dhilon.");
System.out.println("");
return;
}
/*------------------------------------------------------------------------*/
public static int dispMenu()
{
int option = 0;
System.out.print("Please select from one of the following options ");
System.out.println("by typing the corresponding number.");
System.out.println("");
System.out.println("1) Quit Program.");
System.out.println("2) Add a new Student and determine their grade.");
System.out.println("3) View information on all students entered.");
System.out.println("4) View the average mark of all students.");
System.out.print("5) Display the quantities of students above ");
System.out.println("or below the average mark.");
System.out.println("6) Display the distribution of all student's grades.");
System.out.print("7) View all details of a student chosen with their ");
System.out.println("student identification number.");
System.out.print("8) View all details of a student chosen with their ");
System.out.println("full name.");
System.out.println("9) Add a new student and determine if they already exist.");
System.out.println("10) Find the students with the top two marks.");
System.out.println("11) Sort students by student ID and view new order.");
System.out.print("12) Sort students into ascending alphabetical order ");
System.out.println("and view new order.");
System.out.println("");
option = keyBd.nextInt();
return option;
}
/*------------------------------------------------------------------------*/
public static void createNewStud(Student[] Students, boolean func)
{
studCount++;
setStudID(Students);
setStudName(Students);
setPracMark(Students);
setAssigMark(Students, 1);
setAssigMark(Students, 2);
setExamMark(Students);
Students[studCount].setFinMark();
Students[studCount].setFinGrade();
if (func == true)
{
System.out.println("Students grade is: " + Students[studCount].getFinGrade());
}
else
{
detStudExist(Students);
}
return;
}
/*------------------------------------------------------------------------*/
public static void detStudExist(Student[] Students)
{
int checkCount = 0;
for (int index = 0; index < studCount; index++)
{
if((Students[index].checkIfSame(Students[studCount])) && (checkCount < 1))
{
System.out.println("Student already exists! ");
studCount--;
}
}
return;
}
/*------------------------------------------------------------------------*/
public static void setStudID(Student[] Students)
{
int studID = 0;
do
{
System.out.println("Please enter the new students ID number: ");
studID = keyBd.nextInt();
if (studID <= 0)
{
System.out.println("Error, not a valid Student ID");
}
}while(studID <= 0);
Students[studCount].setID(studID);
return;
}
/*------------------------------------------------------------------------*/
public static void setStudName(Student[] Students)
{
System.out.println("Enter student's first name: ");
Students[studCount].setFirstName(keyBd.next());
System.out.println("Enter student's second name: ");
Students[studCount].setLastName(keyBd.next());
return;
}
/*------------------------------------------------------------------------*/
public static void setPracMark(Student[] Students)
{
int mark = -1;
do
{
System.out.println("Please enter student practical mark between 0 and 100: ");
mark = keyBd.nextInt();
}while((mark < 0) ||(mark > 100));
Students[studCount].setPracGrade(mark);
return;
}
/*------------------------------------------------------------------------*/
public static void setAssigMark(Student[] Students, int assigNum)
{
int mark = -1;
do
{
System.out.print("Please enter mark between 0 and 100 for Assignment ");
System.out.println(assigNum + ": ");
mark = keyBd.nextInt();
}while((mark < 0) ||(mark > 100));
switch (assigNum)
{
case 1:
Students[studCount].setAssig1Mark(mark);
break;
case 2:
Students[studCount].setAssig2Mark(mark);
break;
}
return;
}
/*------------------------------------------------------------------------*/
public static void setExamMark(Student[] Students)
{
int mark = -1;
do
{
System.out.println("Please enter mark between 0 and 100 the exam: ");
mark = keyBd.nextInt();
}while((mark < 0) ||(mark > 100));
Students[studCount].setExamGrade(mark);
return;
}
/*------------------------------------------------------------------------*/
public static void printAll(Student[] Students)
{
if (studCount < 0)
{
System.out.println("There are no students currently to display.");
}
else
{
for (int index = 0; index <= studCount; index++)
{
Students[index].outputStudData();
System.out.println("");
System.out.println("");
}
}
return;
}
/*------------------------------------------------------------------------*/
public static double calcAvMark(Student[] Students)
{
int totMark = 0;
double av = 0.0;
if (studCount < 0)
{
System.out.println("There is no students to calculate the average of. ");
}
else
{
for (int index = 0; index <= studCount; index++)
{
totMark += Students[index].getFinMark();
}
av = totMark / (studCount + 1);
System.out.print("The average mark of all students is: ");
System.out.println(av);
}
return av;
}
/*------------------------------------------------------------------------*/
public static void dispDivMarks(Student[] Students, double av)
{
int above = 0; // Above includes 'equal to'.
int below = 0;
double mark = 0.0;
if (av != 0)
{
for (int index = 0; index <= studCount; index++)
{
mark = Students[index].getFinMark();
if (mark >= av)
{
above++;
}
else
{
below++;
}
}
}
System.out.println(above + " Students above or equal to the average grade.");
System.out.println(below + " Students below the average grade.");
return;
}
/*------------------------------------------------------------------------*/
public static void dispDistGrades(Student[] Students)
{
int hd_num = 0;
int d_num = 0;
int c_num = 0;
int p_num = 0;
int n_num = 0;
if(studCount < 0)
{
System.out.println("There are no students to display record of.");
}
else
{
for(int index = 0; index <= studCount; index++)
{
if(Students[index].getFinGrade().equalsIgnoreCase("hd"))
{
hd_num++;
}
else
{
if(Students[index].getFinGrade().equalsIgnoreCase("d"))
{
d_num++;
}
else
{
if(Students[index].getFinGrade().equalsIgnoreCase("c"))
{
c_num++;
}
else
{
if(Students[index].getFinGrade().equalsIgnoreCase("p"))
{
p_num++;
}
else
{
n_num++;
}
}
}
}
}
}
printDist(hd_num, d_num, c_num, p_num, n_num);
return;
}
/*------------------------------------------------------------------------*/
public static void printDist(int hd_num, int d_num, int c_num, int p_num, int n_num)
{
System.out.println("Number of HDs: " + hd_num);
System.out.println("Number of Ds: " + d_num);
System.out.println("Number of Cs: " + c_num);
System.out.println("Number of Ps: " + p_num);
System.out.println("Number of Ns: " + n_num);
System.out.println("");
return;
}
/*------------------------------------------------------------------------*/
public static void findByStudNum(Student[] Students)
{
int IDCheck = 0;
boolean IDExist = false;
if(studCount < 0)
{
System.out.println("There are no records to search");
}
else
{
System.out.println("Please enter Student ID Number for search: ");
IDCheck = keyBd.nextInt();
for(int index = 0; index <= studCount; index++)
{
if(Students[index].getID() == IDCheck)
{
IDExist = true;
Students[index].outputStudData();
}
}
if(IDExist != true)
{
System.out.println("No records exist under the number " + IDCheck);
}
}
return;
}
/*------------------------------------------------------------------------*/
public static void findByStudName(Student[] Students)
{
String fName = "";
String lName = "";
boolean studExist = false;
if(studCount < 0)
{
System.out.println("There are no records to search");
}
else
{
System.out.println("Please enter Student first name: ");
fName = keyBd.next();
System.out.println("Enter Student last name: ");
lName = keyBd.next();
for(int index = 0; index <= studCount; index++)
{
if((Students[index].getFirstName() == fName) && (Students[index].getLastName() == lName))
{
studExist = true;
Students[index].outputStudData();
}
}
if (studExist != true)
{
System.out.print("No records exist under the given name: ");
System.out.println(fName + " " + lName);
}
}
return;
}
/*------------------------------------------------------------------------*/
public static void checkTopGrades(Student[] Students)
{
double highest = 0;
double second = 0;
String topStud = "";
String secStud = "";
if (studCount < 0)
{
System.out.println("No records to search through!");
}
else
{
for(int index = 0; index <= studCount; index++)
{
if (Students[index].getFinMark() > highest)
{
highest = Students[index].getFinMark();
topStud = "" + Students[index].getFirstName() + " " + Students[index].getLastName();
}
}
for(int index1 = 0; index1 <= studCount; index1++)
{
if ((Students[index1].getFinMark() > second) && (Students[index1].getFinMark() != highest))
{
second = Students[index1].getFinMark();
secStud = "" + Students[index1].getFirstName() + " " + Students[index1].getLastName();
}
}
System.out.println("Top Mark was: " + highest + "%");
System.out.println("From Student: " + topStud);
System.out.println("");
System.out.println("Second highest mark is: " + second + "%");
System.out.println("From Student " + secStud);
System.out.println("");
}
return;
}
/*------------------------------------------------------------------------*/
public static void sortStudsNum(Student[] Students)
{
int lowest = MAX_INT;
int newLoc = 0;
if(studCount < 0)
{
System.out.println("There is no data to sort.");
}
else
{
Student[] Students2 = new Student[STUD_MAX];
for(int index = 0; index < STUD_MAX; index++)
{
Students2[index] = new Student(0);
}
System.out.println("Sorted student ID numbers: ");
for(int index1 = 0; index1 <= studCount; index1++)
{
for (int index2 = 0; index2 <= studCount; index2++)
{
if(Students[index2].getID() < lowest)
{
lowest = Students[index2].getID();
newLoc = index2;
}
}
System.out.println(lowest);
Students2[index1] = Students[newLoc];
}
}
return;
}
/*------------------------------------------------------------------------*/
public static void sortStudsAlpha(Student[] Students)
{
String lName = "";
String lastName = "";
int equiv = 0;
int index = 0;
int index2 = 0;
Student temp = new Student(0);
if (studCount < 0)
{
System.out.println("No student entries to sort.");
}
else
{
lastName = Students[index2].getLastName();
for(index = 0; index <= studCount; index++)
{
for (index2 = 0; index2 <= studCount; index2++)
{
lName = Students[index2].getLastName().toLowerCase();
equiv = lastName.compareTo(lName);
if (equiv < 0)
{
temp = Students[index2];
Students[index2] = Students[index2 -1];
Students[index2 -1] = temp;
}
}
}
for(int index3 = 0; index3 <= studCount; index3++)
{
System.out.println(Students[index3].getLastName());
}
}
return;
}
Please, please, please please please can someone help me!? Im usually very good at java but this one has me stumped.
