Mad the executeOnExecutor method public and static and removed the final keyword from the onProgressUpdate method.

Author: Rolf Smit

library/src/main/java/org/neotech/library/retainabletasks/Task.java

@@ -431,7 +431,7 @@ private void doPostExecute() {
      * @see #doInBackground
      */
     @MainThread
-    protected final void onProgressUpdate(Progress values) {
+    protected void onProgressUpdate(Progress values) {
     }
 
     @MainThread

library/src/main/java/org/neotech/library/retainabletasks/TaskExecutor.java

@@ -114,23 +114,23 @@ private TaskExecutor() {
      * @see Task#executeOnExecutor(java.util.concurrent.Executor)
      */
     @MainThread
-    private <Progress, Result> Task<Progress, Result> executeOnExecutor(Task<Progress, Result> task, Executor executor) {
+    public static <Progress, Result> Task<Progress, Result> executeOnExecutor(Task<Progress, Result> task, Executor executor) {
         return task.executeOnExecutor(executor);
     }
 
     @MainThread
     public static <Progress, Result> Task<Progress, Result> execute(Task<Progress, Result> task) {
-        return getInstance().executeOnExecutor(task, sDefaultExecutor);
+        return executeOnExecutor(task, sDefaultExecutor);
     }
 
     @MainThread
     public static <Progress, Result> Task<Progress, Result> executeSerial(Task<Progress, Result> task) {
-        return getInstance().executeOnExecutor(task, SERIAL_EXECUTOR);
+        return executeOnExecutor(task, SERIAL_EXECUTOR);
     }
 
 
     @MainThread
     public static <Progress, Result> Task<Progress, Result> executeParallel(Task<Progress, Result> task) {
-        return getInstance().executeOnExecutor(task, THREAD_POOL_EXECUTOR);
+        return executeOnExecutor(task, THREAD_POOL_EXECUTOR);
     }
 }