JAL-961 ensure we only add one instance of a worker to the registered list of workers...

diff --git a/src/jalview/viewmodel/AlignmentViewport.java b/src/jalview/viewmodel/AlignmentViewport.java
index f14ddd4..8c34f31 100644 (file)
--- a/src/jalview/viewmodel/AlignmentViewport.java
+++ b/src/jalview/viewmodel/AlignmentViewport.java
@@ -371,8 +371,8 @@ public abstract class AlignmentViewport implements AlignViewportI
     {
       return;
     }
-    if (!calculator
-            .startRegisteredWorkersOfClass(jalview.workers.ConservationThread.class))
+    if (calculator
+            .getRegisteredWorkersOfClass(jalview.workers.ConservationThread.class)==null)
     {
       calculator.registerWorker(new jalview.workers.ConservationThread(
               this, ap));
@@ -389,7 +389,7 @@ public abstract class AlignmentViewport implements AlignViewportI
     {
       return;
     }
-    if (!calculator.startRegisteredWorkersOfClass(ConsensusThread.class))
+    if (calculator.getRegisteredWorkersOfClass(ConsensusThread.class)==null)
     {
       calculator.registerWorker(new ConsensusThread(this, ap));
     }
@@ -409,8 +409,8 @@ public abstract class AlignmentViewport implements AlignViewportI
     {
       return;
     }
-    if (!calculator
-            .startRegisteredWorkersOfClass(StrucConsensusThread.class))
+    if (calculator
+            .getRegisteredWorkersOfClass(StrucConsensusThread.class)==null)
     {
       calculator.registerWorker(new StrucConsensusThread(this, ap));
     }