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Start your free trialMehmet Arabaci
4,432 Points[SOLVED] It seems right but doesn't pass. Anyone care to comment why? Is it because we never seem to define queue type?
It seems right but doesn't pass. Anyone care to comment why? Is it because we never seem to define what type of queue this is i.e. an ArrayDeque, where would I do that?
import java.util.ArrayDeque;
import java.util.Queue;
import java.util.*;
public class CallCenter {
Queue<CustomerSupportRep> mSupportReps;
public CallCenter(Queue<CustomerSupportRep> queue) {
mSupportReps = queue;
}
public void acceptCustomer(Customer customer) {
/********************************************
* 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
********************************************
*/
CustomerSupportRep csr;
while (mSupportReps.poll() == null) {
playHoldMusic();
}
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;
}
}
2 Answers
Steve Hunter
57,712 PointsHi there,
To test if the queue is empty; don't use poll()
as this removes any available item in the queue. Use peek()
which just has a look without altering the queue. Use poll()
once there is something in mSupportReps
, as you have done to assign into csr
. The rest of your code looks OK.
Steve.
Mehmet Arabaci
4,432 PointsOkay, yeah definitely helps. Thanks.
Mehmet Arabaci
4,432 PointsMehmet Arabaci
4,432 PointsOkay, thank-you. How come we never initialize Queue<CustomerSupportRep> mSupportReps with the whole = new ArrayDeque<>(); thing? Or has this been done in a class we cant see?
Steve Hunter
57,712 PointsSteve Hunter
57,712 PointsHi there,
I think that there are parts of this program that aren't visible here.
The
queue
is created elsewhere and is passed into the constructor ofCallCenter
. So, wherever that instance ofCallCenter
is created, theQueue
is created there.I hope that helps,
Steve.