bagaimana mengubah program java biasa menjari array

public class Tugas1 {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        // TODO code application logic here
        Scanner input = new Scanner (System.in);
        String nim ,nama , grade ;
        double uts , uas , rata ;

        System.out.println("Data Nilai Mahasiswa");
        System.out.println("NIM");
        nim =input.next();
        System.out.println("NAMA");
        nama =input.next();
        System.out.println("NILAI UTS");
        uts =input.nextDouble();
        System.out.println("NILAI UAS");
        uas =input.nextDouble();

        rata = (uts+uas)/2;

        if(rata<50)
            grade = "E";
        else if(rata<60)
            grade = "D";
        else if(rata<70)
            grade = "C";
        else if(rata<80)
            grade = "B";
        else
            grade = "A";

        System.out.println("==============================================================");
        System.out.println("NIM\tNama\tUTS\tUAS\tN.Rata\tGrade");
        System.out.println("==============================================================");
        System.out.println(nim + "\t" + nama + "\t" + uts +"\t" + uas +"\t" + rata +"\t" + grade);
        System.out.println("==");
        System.out.println("==");

    }

}