Thread: cant run the program with 2 classes

Hi there

i copied below coding from the book.but still cant run the program.i noticed there are two class , they are class student and class obj.i tried separate both class in different class file -> Student.java/Student.class and obj.java/obj.class , but i still cant run the program.Pls help.

Thanks in advance



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public class Student   {
 
private String name; 
private int matricNo; 
private int yearOfBirth; 
private int age; 
private double fees;
private int numberOfCoursesRegistered; 
private String[ ] subjectName; 
private boolean registered= false;
 
public Student(String NAME, int MATRIC, int B_YEAR) { 
 
name= NAME;
yearOfBirth=B_YEAR; 
matricNo= MATRIC; 
numberOfCoursesRegistered=0;
subjectName= new String[3];
 
calculateAge();
 
}
 
private void calculateAge(){
 
int currentYear=2008;
age= currentYear-yearOfBirth;
 
}//calculateAge
 
 
 
public void calculateFee(){ 
 
if (registered==true) 
 
fees=numberOfCoursesRegistered*350; 
 
}//calculateFee
 
 
 
public void registerSubject (String subject1){
 
if (registered==false) {
 
subjectName[0]=subject1;	
numberOfCoursesRegistered=1;
registered=true;
 
}	
 
else
 
  System.out.println("You already registered");
 
 
}// registerSubject
 
 
 
 
public void registerSubject (String subject1, String subject2){
 
if (registered==false) {
 
  subjectName[0]=subject1;
  subjectName[1]=subject2; 
  numberOfCoursesRegistered=2; 
  registered=true; 
}
 
else	
 
  System.out.println("You already registered");  
 
}// registerSubject 
 
public   void   registerSubject   (String   subject1,   String   subject2,   String subject3){
 
 
if (registered==false) {
 
subjectName[0]=subject1; 
subjectName[1]=subject2; 
subjectName[3]=subject3; 
numberOfCoursesRegistered=3; 
registered=true; 
 
} 
 
else
 
  System.out.println("You already registered"); 
}
 
// registerSubject 
 
 
public void displaylnfo ( ) { 
 
  if (registered==true){ 
 
System.out.println("Name: " + name); 
System.out.println("Matric: " + matricNo); 
System.out.println("Year of Birth: " + yearOfBirth); 
System.out.println("age " +age); 
System.out.println("Fees: " + fees);
 
System.out.println("No of courses registered:+numberOfCoursesRegistered"); 
 
System.out.println("Courses registered are:"); 
 
for (int count=0; count < numberOfCoursesRegistered; count++) 
 
System.out.println(subjectName[count]); 
 
} //if 
 
else 
 
  System.out.println("Information cannot be displayed because you have not registered");
 
} //displayInfo 
}//class
 
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class obj{
 
public static void main(String[]args){
 
Student John = new Student ("John Smith" , 2345 , 1969);
 
John.registerSubject("Java Programming");
John.calculateFee();
 
}
}

please wirte
{Student st=new student();
ob.yourrequred method.}