1. I want to keep taking choices from the user until he gives an exit statement.
2. How can I come out of the while loop if I use it in this code?
3. Is there any other way to take choice from the user than switch case:
4. And if I try to use while loop for this then it is going in an infinite loop:

Code:

```
import java.util.Scanner;
class lib
{
public static void main(String args[])
{
    Scanner in=new Scanner(System.in);
    String c;
    int j=5,a=5,s=5,cg=5;
    int d=0;
    System.out.println("Available Copies :");
    System.out.println("java=5,ada=5,sp=5,cg=5");
    System.out.println("enter book title");
    //System.out.println("enter exit for exit if don't want to search");
    c=in.nextLine();
    while(d==0)
    {
        switch(c)
       {
        case "java":
            System.out.println("author is herbert");
            System.out.println("price :500");
            j--;
            break;

        case "ada":

            System.out.println("author is corman");
            System.out.println("price :600");
            a--;
            break;

        case "sp":

            System.out.println("author is dhamdhire");
            System.out.println("price :550");
            s--;
            break;

        case "cg":

            System.out.println("author is pearson");
            System.out.println("price :700");
            cg--;
            break;
        case "exit":
            d++;
            break;

        default:
            System.out.println("book not available");
    }
    }
    if(j!=0)                                      
    System.out.println("number of available copies is"+j);

 }

```