public class CheckOrders implements ActionListener{
// Fields
private JFrame frame;
private JTextArea textArea;
private JTextArea messageArea;
private int NumberOfMachines = 6;
private int MaxQueueForMachine = 10;
private List < Queue<Job> > machineQueues; // List of the Queues of Jobs for each machine.
// use an ArrayList to construct it.
private Map<String, List<Step> > instructions; // Map of list of steps for each product
// use a HashMap to construct it.
private Queue<Job> allJobs; // Queue of all jobs to be processed
// use a LinkedList to construct it.
private boolean moreJobs = false;
// Other Methods
/** Initialise machineQueues to be a List of empty Queues of Jobs,
* one queue for each machine. */
public void initialiseMachineQueues(){
// Hint, note the type of the machineQueues field carefully.
// YOUR CODE HERE
machineQueues = new LinkedList< Queue<Job> >();
}