What is wrong with my program?

// part of the Main function
            Student[] cRecord = new Student[30]; // max no. of
students are 30
            for(int i = 0; i<cRecord.length;i++){
                cRecord[i] = new Student();
            }

            Scanner input = new Scanner(System.in);

                int choice = input.nextInt();

                switch(choice){
                    case 1:
                    {
                        try{

                            System.out.println("Please input the file
name");
                            Scanner userin = new Scanner(System.in);
                            String filename = userin.next();
                            userin.nextLine();

                            File inputfile = new File(filename);
                            if (!inputfile.exists()){
                                throw new FileNotFoundException("File
not file" + filename);
                            }

                            readFile(inputfile, cRecord);
                            Arrays.sort(cRecord,new
NameComparator()); // error occurs here

                            userin.close();

                        }
                        catch (FileNotFoundException ex){
                            System.err.println(ex);
                        }

                    }
                    break;
        .....
        }

/*****************************readFile function--
***************************************/
static void readFile(File inputfile,Student[] stds){
        try{
            FileInputStream fis = new FileInputStream(inputfile);
            BufferedInputStream bis = new BufferedInputStream(fis);
            DataInputStream fileinput = new DataInputStream(bis);
            BufferedReader br = new BufferedReader(new
InputStreamReader(fileinput));

            String read;
            int i = 0;
                while((read=br.readLine())!=null){
                    if(read.contains("Student ID = ")){
                        System.out.println("Student ID");
                         String caid =
read.substring(read.lastIndexOf("=") + 1);
                         int aid = Integer.parseInt(caid);
                         stds[i].setAccId(aid);

                    }
                    else if(read.contains("Name = ")){
                        System.out.println("Name");
                        String cname =
read.substring(read.lastIndexOf("=") + 1);
                        char[] name =
cname.toUpperCase().toCharArray();
                        stds[i].setName(name);

                    }
                    else if(read.contains("Address = ")){
                        System.out.println("Address");
                        String caddress =
read.substring(read.lastIndexOf("=") + 1);
                        char[] add = caddress.toCharArray();
                        stds[i].setAddress(add);
                    }
                }

            fileinput.close();
        }
        catch (IOException ex){
            System.err.println(ex);
        }
    }

/*****************************NameComparator class********************
package lab2;
import java.util.Comparator;
public class NameComparator implements Comparator{
    public int compareObject(Object cust, Object anotherStudent){
        char[] shortName1 = ((Student) cust).getName();
        char[] shortName2 = ((Student) anotherStudent).getName();

        String sName1 = new String(shortName1);
        String sName2 = new String(shortName2);

        if(!(sName1.equals(sName2))){
            return sName1.compareTo(sName2);
        }

        return 0;

    }

    public int compare(Object o1, Object o2) {
        throw new UnsupportedOperationException("Not supported yet.");
    }

}

/***************************Students.txt*****************************
Student Id = 123
name = Matt Damon
Address = 465 Ripley Boulevard, Oscar Mansion,

Student Id = 126
name = Ben Affleck
Address = 200 Hunting Street

Student Id = 65
name = Salma Hayek
Address = 45 Mexican Boulevard, Hotel california

************************Problem******************************
Please input the file name:
students.txt
Exception in thread "main" java.lang.UnsupportedOperationException:
Not supported yet.
        at lab2.NameComparator.compare(NameComparator.java:21)
        at java.util.Arrays.mergeSort(Arrays.java:1270)
        at java.util.Arrays.mergeSort(Arrays.java:1281)
        at java.util.Arrays.mergeSort(Arrays.java:1281)
        at java.util.Arrays.mergeSort(Arrays.java:1281)
        at java.util.Arrays.sort(Arrays.java:1210)
        at lab2.Main.main(Main.java:46)

I want to Read data from file(student.txt), then sort the list in
ascending order. One more question, i want to reports the number of
students records successfully read as its return value and no
duplicate record should be read in. How can I do that?