Java: Input error

When I use one object of class Scanner for two object of user defined class. Compiler skips some input taking line. As mentioned below.

1) Scanner obj = new Scanner(System.in);

2) GradeBook book1 = new GradeBook();
3) GradeBook book2 = new GradeBook();

//input for book1

4) variable1 = obj.nextInt();
5) book1.variable1 = variable1;
6) variable2 = obj.nextInt();
7) book1.variable1 = variable2;
8) variable3 = obj.nextInt();
9) book1.variable1 = variable3;

//input for book2

10) variable1 = obj.nextInt();
11) book2.variable1 = variable1;
12) variable2 = obj.nextInt();
13) book2.variable1 = variable2;
14) varibale3 = obj.nextInt();
15) book2.variable1 = variable3;

It skips line No 10 (it does not read this line variable1 = obj.nextInt();).

But when I use two different objects of Scanner class, one for book1 and second for book2, then it works fine.

Whats the problem, why happens like this?

import java.util.Scanner;
public class GradeTest {

    /**
     * @param args
     */ 
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);

        try{
        Employee employee1 = new Employee();
        Employee employee2 = new Employee();

        String fName,lName;
        double salary;              

        System.out.print("Enter first name:");
        fName = input.nextLine();
        employee1.SetFName(fName);
        System.out.print("\nEnter last name:");             
        lName = inp.nextLine();
        employee1.SetLName(lName);
        System.out.print("\nEnter salary:");
        salary = inp.nextDouble();
        employee1.SetSalary(salary);

        System.out.printf("\n1:Updated Value \n FName : %s  LName : %s  Salary : %.2f ", employee1.GetFName(),employee1.GetLName(),employee1.GetSalary());

Systm.out.println("Enter data for second employee. \n");

        System.out.print("Enter first name:");
        lName = input.nextLine();
        employee2.SetFName(fName);
        System.out.print("\nEnter last name:");
        lName = input.nextLine();
        employee2.SetLName(lName);
        System.out.print("\nEnter salary:");
        salary = input.nextDouble();
        employee2.SetSalary(salary);

            System.out.printf("\n2:Initial Value \n FName : %s  LName : %s  Salary : %.2f ", employee2.GetFName(),employee2.GetLName(),employee2.GetSalary());
                }
        finally{
                inp.close();
        }
    }
}

Expected output:

Enter first name: First Name1
Enter last name:  Last Name1                
Enter salary: 1500.00

Enter data for second employee.

Enter first name: First Name2
Enter last name:  Last Name2                
Enter salary: 1200.00

Actual output:

Enter first name: First Name1
Enter last name:  Last Name1                
Enter salary: 1500.00

Enter data for second employee.

Enter first name: 
Enter last name:  Last Name2                
Enter salary: 1200.00