[tests] More cleanup

Author: hazendaz

src/test/java/org/mybatis/spring/asyncsynchronization/AsyncAfterCompletionHelper.java

@@ -66,9 +66,8 @@ public Object invoke(final Object proxy, final Method method, final Object[] arg
       thread.join();
       if (exceptionSet.isEmpty()) {
         return retValSet.iterator().next();
-      } else {
-        throw exceptionSet.iterator().next();
       }
+      throw exceptionSet.iterator().next();
     }
 
   }

src/test/java/org/mybatis/spring/submitted/xa/UserServiceImpl.java

@@ -44,7 +44,7 @@ public void saveWithFailure(User user) {
 
   @Override
   public boolean checkUserExists(int id) {
-    if ((userMapperMaster.select(id) != null) || (userMapperSlave.select(id) != null)) {
+    if (userMapperMaster.select(id) != null || userMapperSlave.select(id) != null) {
       return true;
     }
     return false;