code

import java.io.*;
class LMS
{
String s_fname,s_lname;
int s_class, rollno,no_of_books,s_no_of_books,issue_date,return_date;
String b_name[]=new String[100];
String author_name[]=new String[100];
String publication[]=new String[100];
int book_no[]=new int[100];
public void enter_student()throws Exception
{
DataInputStream in=new DataInputStream(System.in);
System.out.println("Enter the details of student");
System.out.println("Enter first name");
s_fname=in.readLine();
System.out.println("Enter last name");
s_lname=in.readLine();
System.out.println("Enter class");
s_class=Integer.parseInt(in.readLine());
System.out.println("Enter roll no. ");
rollno=Integer.parseInt(in.readLine());
System.out.println("Enter the number of books already issued by student");
s_no_of_books=Integer.parseInt(in.readLine());
}
public void enter_book()throws Exception
{
int i;
DataInputStream in=new DataInputStream(System.in);
System.out.println("Enter the number of books");
no_of_books=Integer.parseInt(in.readLine());
System.out.println("Enter the details of book");
for(i=0;i<no_of_books;i++)
{
System.out.println("Enter name of book");
b_name[i]=in.readLine();
System.out.println("Enter author of book");
author_name[i]=in.readLine();
System.out.println("Enter publication");
publication[i]=in.readLine();
System.out.println("Enter book no. ");
book_no[i]=Integer.parseInt(in.readLine());
}
}
public void display_student()
{
System.out.println(" First name of student is - " +s_fname);
System.out.println(" Last name of student is - " +s_lname);
System.out.println("Student is of class - "+s_class);
System.out.println("Roll number of student is - "+rollno);
System.out.println("Number of books issued by the student is - "+s_no_of_books);
}
public void display_book()
{
int i;
for(i=0;i<no_of_books;i++)
{
System.out.println("Name of book is - " +b_name[i]);
System.out.println("Author of book is - " +author_name[i]);
System.out.println("Publication of book is - " +publication[i]);
System.out.println("Book number is - "+book_no[i]);
}
}
public int search(int b)
{
int i,f=0;
for(i=0;i<no_of_books;i++)
{
if(book_no[i]==b)
{
f=1;
break;
}
}
if(f==1)
return(1);
else
return(0);
}
public void issue()throws Exception
{
int a,bn;
DataInputStream in=new DataInputStream(System.in);
System.out.println("Enter the book number of the book to be issued");
bn=Integer.parseInt(in.readLine());
a=search(bn);
if(a==1)
{
if(s_no_of_books<2)
{
System.out.println("Book is present and can be issued");
System.out.println("Enter the date when the book is getting issued");
issue_date=Integer.parseInt(in.readLine());
}
else
System.out.println("Student already issued 2 books and can't issue any other book now");
}
else
System.out.println("Book is not present and so can't be issued");
}
public void modify_student()throws Exception
{
int ch;
DataInputStream in=new DataInputStream(System.in);
System.out.println("Enter your choice what detail of student you want to modify");
System.out.println("1 - Modify first name of student");
System.out.println("2 - Modify last name of student");
System.out.println("3 - Modify class in which student is studying");
System.out.println("4 - Modify roll number of student");
System.out.println("5 - Modify the number of books issued by student");
ch=Integer.parseInt(in.readLine());
if(ch==1)
{
System.out.println("Enter modified first name");
s_fname=in.readLine();
}
else if(ch==2)
{
System.out.println("Enter modified last name");
s_lname=in.readLine();
}
else if(ch==3)
{
System.out.println("Enter the class in which student is studying now");
s_class=Integer.parseInt(in.readLine());
}
else if(ch==4)
{
System.out.println("Enter roll number of student ");
rollno=Integer.parseInt(in.readLine());
}
else if(ch==5)
{
System.out.println("Enter the number of books already issued by student");
s_no_of_books=Integer.parseInt(in.readLine());
}
}
public void return_book()throws Exception
{
int r_no_of_books,bn,i;
DataInputStream in=new DataInputStream(System.in);
System.out.println("Enter the book number of the book to be returned");
bn=Integer.parseInt(in.readLine());
System.out.println("Enter the date when the book is being returned");
return_date=Integer.parseInt(in.readLine());
System.out.println("Book returned");
s_no_of_books=s_no_of_books-1;
}
public void fine()
{
int d,s_fine;
d=return_date-issue_date;
if(d<=7)
s_fine=0;
else
s_fine=d-7;  // As the fine is according to Rs.1 per day after 7 days
System.out.println("Fine to be paid by student is - "+s_fine);
}

public static void main(String arg[])throws Exception
{
int a,b_search;
LMS obj=new LMS();
int choice=1;
DataInputStream in=new DataInputStream(System.in);
System.out.println("---------Welcome to Samarpit's Library---------");

while(choice!=0)
{
System.out.println("Enter the choice as :-");
System.out.println("0-Exit");
System.out.println("1- Entering Student's information");
System.out.println("2- Entering book's details");
System.out.println("3- Displaying Student's information");
System.out.println("4- Displaying details of book");
System.out.println("5- Searching book");
System.out.println("6- Issuing book");
System.out.println("7- Modifying student's details");
System.out.println("8- Returning book");
System.out.println("9- Checking fine");
choice=Integer.parseInt(in.readLine());
switch(choice)
{
case 0:
break;
case 1:
obj.enter_student();
break;
case 2:
obj.enter_book();
break;
case 3:
obj.display_student();
break;
case 4:
obj.display_book();
break;
case 5:
System.out.println("Enter the book number of the book which is to be searched");
b_search=Integer.parseInt(in.readLine());
a=obj.search(b_search);
if(a==1)
System.out.println("Book is present ");
else
System.out.println("Book is not present ");
break;
case 6:
obj.issue();
break;
case 7:
obj.modify_student();
break;
case 8:
obj.return_book();
break;
case 9:
obj.fine();
break;
default:
System.out.println("Enter correct choice as per the list above");
break;
}
}
}
}