Can you help me fix my java code.

package assignment5;

import java.util.ArrayList; import java.util.Date;

public class Controller { private static final String[] studentCode= {"s100","s200","s300"}; private static final String[] studentName= {"student1","student2","student3"}; private static final int[] studentCredit= {20,25,15}; private static final String[] courseCode= {"cs1000","cs2000","cs3000"}; private static final String[] courseName= {"Java","C++","Android"}; private static final int[] courseCredit= {4,4,3}; private static final String[] regStudentCode= {"s100","s100","s200","s200","s300","s300"}; private static final String[] regCourseCode= {"cs1000","cs2000","cs1000","cs2000","cs2000","cs3000"}; private static final String[] regDate= {"2019/1/09","2019/1/10","2019/1/15","2019/1/09","2019/1/10","2019/1/15"}; private ArrayList courses; private ArrayList students; private ArrayList enrollments; public Controller() { courses=new ArrayList(); students=new ArrayList(); enrollments=new ArrayList(); fillLists(); } private void fillLists() { for(int i=0;i