Java Coding Problems

Per-thread context

Let's assume that we have the following Order class:

public class Order {  private final int customerId;  public Order(int customerId) {    this.customerId = customerId;  }  // getter and toString() omitted for brevity}

And, we write CustomerOrder as follows:

public class CustomerOrder implements Runnable {  private static final Logger logger    = Logger.getLogger(CustomerOrder.class.getName());  private static final Random rnd = new Random();  private static final ThreadLocal<Order>     customerOrder = new ThreadLocal<>();  private final int customerId;  public CustomerOrder(int customerId) {    this.customerId = customerId;  }  @Override  public void run() {    logger.info(() -> "Given customer id: " + customerId  + " | " + customerOrder.get() ...