Welcome to the Treehouse Community
Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.
Looking to learn something new?
Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.
Start your free trialAndrew Foust
13,228 PointsGetting stuck on the Call Center quiz.
I am able to play the wait music fine with a do while loop. I seem to be calling assist because I'm seeing the messaging in the preview. When I try to add the csr back to the queue I always get an error asking if I called assist.
import java.util.ArrayDeque;
import java.util.Queue;
public class CallCenter {
Queue<CustomerSupportRep> mSupportReps;
public CallCenter(Queue<CustomerSupportRep> queue) {
mSupportReps = queue;
}
public void acceptCustomer(Customer customer) {
CustomerSupportRep csr;
/********************************************
* TODO (1)
* Wait until there is an available rep in the queue.
* While there is not one available, playHoldMusic
* HINT: That while assignmentcheck loop syntax we used to
* read files seems pretty similar
********************************************
*/
do {
playHoldMusic();
} while((mSupportReps.poll()) == null);
csr = mSupportReps.poll();
/********************************************
* TODO (2)
* After we have assigned the rep, call the
* assist method and pass in the customer
********************************************
*/
csr.assist(customer);
/********************************************
* TODO (3)
* Since the customer support rep is done with
* assisting, put them back into the queue.
********************************************
*/
mSupportReps.add(csr);
}
public void playHoldMusic() {
System.out.println("Smooooooth Operator.....");
}
}
import java.util.List;
import java.util.ArrayList;
public class CustomerSupportRep {
private String mName;
private List<Customer> mAssistedCustomers;
public CustomerSupportRep(String name) {
mName = name;
mAssistedCustomers = new ArrayList<Customer>();
}
public void assist(Customer customer) {
System.out.printf("Hello %s, my name is %s, how can I assist you.%n",
customer.getName(),
mName);
System.out.println("...");
System.out.println("Is there anything else I can help you with?");
mAssistedCustomers.add(customer);
}
public List<Customer> getAssistedCustomers() {
return mAssistedCustomers;
}
}
public class Customer {
private String mName;
public Customer(String name) {
mName = name;
}
public String getName() {
return mName;
}
}
1 Answer
Christopher Augg
21,223 PointsHello Andrew,
When you use the poll method it removes the head item from the queue. Therefore, if you poll again and the item is no longer there, you cannot retrieve it. You should consider a different queue method. You can look at the following for a good reference:
http://docs.oracle.com/javase/7/docs/api/java/util/Queue.html
Regards,
Chris