code: public synchronized void  pruneFinishedTasks()
      {
          final ArrayList<IExecutionBridge> nonFinishedBridges = new ArrayList<>();
          for (final IExecutionBridge bridge: this.executionBridges) {
              if (!bridge.isFinished()) {
                  nonFinishedBridges.add(bridge);
              }
          }
          this.executionBridges = nonFinishedBridges;
      }
docs: Prune finished tasks.