Class ListenerOrderDeterminer

java.lang.Object
org.testng.internal.ListenerOrderDeterminer

public final class ListenerOrderDeterminer extends Object
A Utility that helps us differentiate between a user's listener and preferential Listener.

When dealing with TestNG listeners we would need to ensure that the user created listeners are invoked first followed by Preferential listeners. This is required so that we always honour any state changes that a user's listener may have done to the internal state of objects that can affect the outcome of the execution (for e.g.,ITestResult)

The ordering must be done such that, when dealing with "beforeXXX|afterXXX" we group all the IDE listeners at the end. That way, we can always ensure that the preferential listeners (for e.g., IDE listeners) always honour the changes that were done to the TestNG internal states and give a consistent experience for users.

  • Method Details

    • order

      public static <T extends ITestNGListener> List<T> order(Collection<T> original, ListenerComparator comparator)
      Parameters:
      original - - The original collection of listeners
      Returns:
      - A re-ordered collection wherein preferential listeners are added at the end
    • reversedOrder

      public static <T extends ITestNGListener> List<T> reversedOrder(Collection<T> original, ListenerComparator comparator)
      Parameters:
      original - - The original collection of listeners
      Returns:
      - A reversed ordered list wherein the user listeners are found in reverse order followed by preferential listeners also in reverse order.