diff --git a/dhis-2/dhis-api/src/main/java/org/hisp/dhis/scheduling/JobProgress.java b/dhis-2/dhis-api/src/main/java/org/hisp/dhis/scheduling/JobProgress.java
index a953046eb56d..dfdb6f694075 100644
--- a/dhis-2/dhis-api/src/main/java/org/hisp/dhis/scheduling/JobProgress.java
+++ b/dhis-2/dhis-api/src/main/java/org/hisp/dhis/scheduling/JobProgress.java
@@ -83,16 +83,14 @@
  *       form of a loop.
  * </ol>
  *
- * For each of the three levels a new node is announced up front by calling the corresponding {@link
- * #startingProcess(String)}, {@link #startingStage(String)} or {@link #startingWorkItem(String)}
- * method.
+ * For each of the three levels a new node is announced up front by calling the corresponding {@code
+ * startingProcess}, {@code startingStage} or {@code startingWorkItem} method.
  *
- * <p>The process will now expect a corresponding completion, for example {@link
- * #completedWorkItem(String)} in case of success or {@link #failedWorkItem(String)} in case of an
- * error. The different {@link #runStage(Stream, Function, Consumer)} or {@link
- * #runStageInParallel(int, Collection, Function, Consumer)} helpers can be used to do the error
- * handling correctly and make sure the work items are completed in both success and failure
- * scenarios.
+ * <p>The process will now expect a corresponding completion, for example {@code completedWorkItem}
+ * in case of success or {@code failedWorkItem} in case of an error. The different {@link
+ * #runStage(Stream, Function, Consumer)} or {@link #runStageInParallel(int, Collection, Function,
+ * Consumer)} helpers can be used to do the error handling correctly and make sure the work items
+ * are completed in both success and failure scenarios.
  *
  * <p>For stages that do not have work items {@link #runStage(Runnable)} and {@link
  * #runStage(Object, Callable)} can be used to make sure completion is handled correctly.
@@ -115,7 +113,7 @@
  * cooperatively by not starting any further work.
  *
  * <p>When a stage is cancelled the run-methods usually return false to give caller a chance to
- * react if needed. The next call to {@link #startingStage(String)} will then throw a {@link
+ * react if needed. The next call to {@code startingStage} will then throw a {@link
  * CancellationException} and thereby short-circuit the rest of the process.
  *
  * @author Jan Bernitt
@@ -206,17 +204,17 @@ default void addError(
    * Tracking API:
    */
 
-  void startingProcess(String description, Object... args);
+  void startingProcess(@CheckForNull String description, Object... args);
 
   default void startingProcess() {
     startingProcess(null);
   }
 
-  void completedProcess(String summary, Object... args);
+  void completedProcess(@CheckForNull String summary, Object... args);
 
-  void failedProcess(String error, Object... args);
+  void failedProcess(@CheckForNull String error, Object... args);
 
-  default void failedProcess(Exception cause) {
+  default void failedProcess(@Nonnull Exception cause) {
     failedProcess("Process failed: {}", getMessage(cause));
   }
 
@@ -237,44 +235,44 @@ default void endingProcess(boolean success) {
    * @throws CancellationException in case cancellation has been requested before this stage had
    *     started
    */
-  void startingStage(String description, int workItems, FailurePolicy onFailure)
+  void startingStage(@Nonnull String description, int workItems, @Nonnull FailurePolicy onFailure)
       throws CancellationException;
 
-  default void startingStage(String description, int workItems) {
+  default void startingStage(@Nonnull String description, int workItems) {
     startingStage(description, workItems, FailurePolicy.PARENT);
   }
 
-  default void startingStage(String description, FailurePolicy onFailure) {
+  default void startingStage(@Nonnull String description, @Nonnull FailurePolicy onFailure) {
     startingStage(description, 0, onFailure);
   }
 
-  default void startingStage(String description, Object... args) {
+  default void startingStage(@Nonnull String description, Object... args) {
     startingStage(format(description, args), FailurePolicy.PARENT);
   }
 
-  void completedStage(String summary, Object... args);
+  void completedStage(@CheckForNull String summary, Object... args);
 
-  void failedStage(String error, Object... args);
+  void failedStage(@Nonnull String error, Object... args);
 
-  default void failedStage(Exception cause) {
+  default void failedStage(@Nonnull Exception cause) {
     failedStage(getMessage(cause));
   }
 
-  default void startingWorkItem(String description, Object... args) {
+  default void startingWorkItem(@Nonnull String description, Object... args) {
     startingWorkItem(format(description, args), FailurePolicy.PARENT);
   }
 
-  void startingWorkItem(String description, FailurePolicy onFailure);
+  void startingWorkItem(@Nonnull String description, @Nonnull FailurePolicy onFailure);
 
   default void startingWorkItem(int i) {
     startingWorkItem("#" + (i + 1));
   }
 
-  void completedWorkItem(String summary, Object... args);
+  void completedWorkItem(@CheckForNull String summary, Object... args);
 
-  void failedWorkItem(String error, Object... args);
+  void failedWorkItem(@Nonnull String error, Object... args);
 
-  default void failedWorkItem(Exception cause) {
+  default void failedWorkItem(@Nonnull Exception cause) {
     failedWorkItem(getMessage(cause));
   }
 
@@ -288,7 +286,7 @@ default void failedWorkItem(Exception cause) {
    * @param items the work items to run in the sequence to run them
    * @see #runStage(Collection, Function, Consumer)
    */
-  default void runStage(Collection<Runnable> items) {
+  default void runStage(@Nonnull Collection<Runnable> items) {
     runStage(items, item -> null, Runnable::run);
   }
 
@@ -299,7 +297,7 @@ default void runStage(Collection<Runnable> items) {
    *     description. Items are processed in map iteration order.
    * @see #runStage(Collection, Function, Consumer)
    */
-  default void runStage(Map<String, Runnable> items) {
+  default void runStage(@Nonnull Map<String, Runnable> items) {
     runStage(items.entrySet(), Entry::getKey, entry -> entry.getValue().run());
   }
 
@@ -314,7 +312,9 @@ default void runStage(Map<String, Runnable> items) {
    * @see #runStage(Collection, Function, Consumer)
    */
   default <T> void runStage(
-      Collection<T> items, Function<T, String> description, Consumer<T> work) {
+      @Nonnull Collection<T> items,
+      @Nonnull Function<T, String> description,
+      @Nonnull Consumer<T> work) {
     runStage(items.stream(), description, work);
   }
 
@@ -324,7 +324,10 @@ default <T> void runStage(
    *
    * @see #runStage(Stream, Function, Consumer,BiFunction)
    */
-  default <T> void runStage(Stream<T> items, Function<T, String> description, Consumer<T> work) {
+  default <T> void runStage(
+      @Nonnull Stream<T> items,
+      @Nonnull Function<T, String> description,
+      @Nonnull Consumer<T> work) {
     runStage(
         items,
         description,
@@ -346,10 +349,10 @@ default <T> void runStage(Stream<T> items, Function<T, String> description, Cons
    * @param <T> type of work item input
    */
   default <T> void runStage(
-      Stream<T> items,
-      Function<T, String> description,
-      Consumer<T> work,
-      BiFunction<Integer, Integer, String> summary) {
+      @Nonnull Stream<T> items,
+      @Nonnull Function<T, String> description,
+      @Nonnull Consumer<T> work,
+      @CheckForNull BiFunction<Integer, Integer, String> summary) {
     runStage(
         items,
         description,
@@ -377,11 +380,11 @@ default <T> void runStage(
    * @param <T> type of work item input
    */
   default <T, R> void runStage(
-      Stream<T> items,
-      Function<T, String> description,
-      Function<R, String> result,
-      Function<T, R> work,
-      BiFunction<Integer, Integer, String> summary) {
+      @Nonnull Stream<T> items,
+      @Nonnull Function<T, String> description,
+      @CheckForNull Function<R, String> result,
+      @Nonnull Function<T, R> work,
+      @CheckForNull BiFunction<Integer, Integer, String> summary) {
     int i = 0;
     int failed = 0;
     for (Iterator<T> it = items.iterator(); it.hasNext(); ) {
@@ -423,7 +426,7 @@ default <T, R> void runStage(
    * @return true, if stage is/was skipped (complected as failed), false otherwise
    */
   default boolean autoSkipStage(
-      BiFunction<Integer, Integer, String> summary, int success, int failed) {
+      @CheckForNull BiFunction<Integer, Integer, String> summary, int success, int failed) {
     if (isSkipCurrentStage()) {
       String text = summary == null ? "" : summary.apply(success, failed);
       if (isCancelled()) {
@@ -439,7 +442,7 @@ default boolean autoSkipStage(
   /**
    * @see #runStage(Function, Runnable)
    */
-  default boolean runStage(Runnable work) {
+  default boolean runStage(@Nonnull Runnable work) {
     return runStage(null, work);
   }
 
@@ -454,7 +457,8 @@ default boolean runStage(Runnable work) {
    * @param work work for the entire stage
    * @return true, if completed successful, false if completed exceptionally
    */
-  default boolean runStage(Function<Boolean, String> summary, Runnable work) {
+  default boolean runStage(
+      @CheckForNull Function<Boolean, String> summary, @Nonnull Runnable work) {
     return runStage(
         false,
         summary,
@@ -464,14 +468,15 @@ default boolean runStage(Function<Boolean, String> summary, Runnable work) {
         });
   }
 
-  default <T> T runStage(Callable<T> work) {
+  @CheckForNull
+  default <T> T runStage(@Nonnull Callable<T> work) {
     return runStage(null, work);
   }
 
   /**
    * @see #runStage(Object, Function, Callable)
    */
-  default <T> T runStage(T errorValue, Callable<T> work) {
+  default <T> T runStage(@CheckForNull T errorValue, @Nonnull Callable<T> work) {
     return runStage(errorValue, null, work);
   }
 
@@ -488,7 +493,10 @@ default <T> T runStage(T errorValue, Callable<T> work) {
    * @return the value returned by work task when successful or the errorValue in case the task
    *     threw an {@link Exception}
    */
-  default <T> T runStage(T errorValue, Function<T, String> summary, Callable<T> work) {
+  default <T> T runStage(
+      @CheckForNull T errorValue,
+      @CheckForNull Function<T, String> summary,
+      @Nonnull Callable<T> work) {
     try {
       T res = work.call();
       completedStage(summary == null ? null : summary.apply(res));
@@ -518,7 +526,10 @@ default <T> T runStage(T errorValue, Function<T, String> summary, Callable<T> wo
    * @param <T> type of work item input
    */
   default <T> void runStageInParallel(
-      int parallelism, Collection<T> items, Function<T, String> description, Consumer<T> work) {
+      int parallelism,
+      @Nonnull Collection<T> items,
+      @Nonnull Function<T, String> description,
+      @Nonnull Consumer<T> work) {
     if (parallelism <= 1) {
       runStage(items, description, work);
       return;
@@ -580,7 +591,7 @@ default <T> void runStageInParallel(
    * @param args the pattern arguments.
    * @return a formatted message string.
    */
-  default String format(String pattern, Object... args) {
+  default String format(@CheckForNull String pattern, Object... args) {
     return pattern != null ? MessageFormatter.arrayFormat(pattern, args).getMessage() : null;
   }
 
@@ -602,8 +613,7 @@ enum Status {
    *
    * <p>The implementation of {@link FailurePolicy} is done by affecting {@link
    * #isSkipCurrentStage()} and {@link #isCancelled()} accordingly after the failure occurred and
-   * has been tracked using one of the {@link #failedStage(String)} or {@link
-   * #failedWorkItem(String)} methods.
+   * has been tracked using one of the {@code failedStage} or {@code failedWorkItem} methods.
    */
   enum FailurePolicy {
     /**
@@ -880,7 +890,8 @@ public Item(
     }
   }
 
-  static String getMessage(Exception cause) {
+  @Nonnull
+  static String getMessage(@Nonnull Exception cause) {
     String msg = cause.getMessage();
     return msg == null || msg.isBlank() ? cause.getClass().getName() : msg;
   }
diff --git a/dhis-2/dhis-api/src/main/java/org/hisp/dhis/scheduling/NoopJobProgress.java b/dhis-2/dhis-api/src/main/java/org/hisp/dhis/scheduling/NoopJobProgress.java
index 5a04442993d1..f57f9a9dc979 100644
--- a/dhis-2/dhis-api/src/main/java/org/hisp/dhis/scheduling/NoopJobProgress.java
+++ b/dhis-2/dhis-api/src/main/java/org/hisp/dhis/scheduling/NoopJobProgress.java
@@ -27,6 +27,9 @@
  */
 package org.hisp.dhis.scheduling;
 
+import javax.annotation.CheckForNull;
+import javax.annotation.Nonnull;
+
 /**
  * The {@link NoopJobProgress} can be used as a {@link JobProgress} instance when no actual flow
  * control and tracking is wanted. For example in test context or in manual runs of operations that
@@ -52,12 +55,13 @@ public void completedProcess(String summary, Object... args) {
   }
 
   @Override
-  public void failedProcess(String error, Object... args) {
+  public void failedProcess(@CheckForNull String error, Object... args) {
     // as the name said we do nothing
   }
 
   @Override
-  public void startingStage(String description, int workItems, FailurePolicy onFailure) {
+  public void startingStage(
+      @Nonnull String description, int workItems, @Nonnull FailurePolicy onFailure) {
     // as the name said we do nothing
   }
 
@@ -67,12 +71,12 @@ public void completedStage(String summary, Object... args) {
   }
 
   @Override
-  public void failedStage(String error, Object... args) {
+  public void failedStage(@Nonnull String error, Object... args) {
     // as the name said we do nothing
   }
 
   @Override
-  public void startingWorkItem(String description, FailurePolicy onFailure) {
+  public void startingWorkItem(@Nonnull String description, @Nonnull FailurePolicy onFailure) {
     // as the name said we do nothing
   }
 
@@ -82,7 +86,7 @@ public void completedWorkItem(String summary, Object... args) {
   }
 
   @Override
-  public void failedWorkItem(String error, Object... args) {
+  public void failedWorkItem(@Nonnull String error, Object... args) {
     // as the name said we do nothing
   }
 }
diff --git a/dhis-2/dhis-services/dhis-service-core/src/main/java/org/hisp/dhis/scheduling/NotifierJobProgress.java b/dhis-2/dhis-services/dhis-service-core/src/main/java/org/hisp/dhis/scheduling/NotifierJobProgress.java
index d31f5e720c0a..8b4aa3bfe85e 100644
--- a/dhis-2/dhis-services/dhis-service-core/src/main/java/org/hisp/dhis/scheduling/NotifierJobProgress.java
+++ b/dhis-2/dhis-services/dhis-service-core/src/main/java/org/hisp/dhis/scheduling/NotifierJobProgress.java
@@ -32,6 +32,8 @@
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import java.util.concurrent.atomic.AtomicBoolean;
+import javax.annotation.CheckForNull;
+import javax.annotation.Nonnull;
 import lombok.RequiredArgsConstructor;
 import org.hisp.dhis.system.notification.NotificationDataType;
 import org.hisp.dhis.system.notification.NotificationLevel;
@@ -79,12 +81,13 @@ public void completedProcess(String summary, Object... args) {
   }
 
   @Override
-  public void failedProcess(String error, Object... args) {
+  public void failedProcess(@CheckForNull String error, Object... args) {
     notifier.notify(jobId, NotificationLevel.ERROR, format(error, args), true);
   }
 
   @Override
-  public void startingStage(String description, int workItems, FailurePolicy onFailure) {
+  public void startingStage(
+      @Nonnull String description, int workItems, @Nonnull FailurePolicy onFailure) {
     stageItems = workItems;
     stageItem = 0;
     if (isNotEmpty(description)) {
@@ -100,14 +103,14 @@ public void completedStage(String summary, Object... args) {
   }
 
   @Override
-  public void failedStage(String error, Object... args) {
+  public void failedStage(@Nonnull String error, Object... args) {
     if (isNotEmpty(error)) {
       notifier.notify(jobId, NotificationLevel.ERROR, format(error, args), false);
     }
   }
 
   @Override
-  public void startingWorkItem(String description, FailurePolicy onFailure) {
+  public void startingWorkItem(@Nonnull String description, @Nonnull FailurePolicy onFailure) {
     if (isNotEmpty(description)) {
       String nOf = "[" + (stageItems > 0 ? stageItem + "/" + stageItems : "" + stageItem) + "] ";
       notifier.notify(jobId, NotificationLevel.LOOP, nOf + description, false);
@@ -124,7 +127,7 @@ public void completedWorkItem(String summary, Object... args) {
   }
 
   @Override
-  public void failedWorkItem(String error, Object... args) {
+  public void failedWorkItem(@Nonnull String error, Object... args) {
     if (isNotEmpty(error)) {
       notifier.notify(jobId, NotificationLevel.ERROR, format(error, args), false);
     }
diff --git a/dhis-2/dhis-services/dhis-service-core/src/main/java/org/hisp/dhis/scheduling/RecordingJobProgress.java b/dhis-2/dhis-services/dhis-service-core/src/main/java/org/hisp/dhis/scheduling/RecordingJobProgress.java
index 2dba2ef60380..a4b501dad374 100644
--- a/dhis-2/dhis-services/dhis-service-core/src/main/java/org/hisp/dhis/scheduling/RecordingJobProgress.java
+++ b/dhis-2/dhis-services/dhis-service-core/src/main/java/org/hisp/dhis/scheduling/RecordingJobProgress.java
@@ -231,7 +231,7 @@ public void completedProcess(String summary, Object... args) {
   }
 
   @Override
-  public void failedProcess(String error, Object... args) {
+  public void failedProcess(@CheckForNull String error, Object... args) {
     observer.run();
 
     String message = format(error, args);
@@ -250,7 +250,7 @@ public void failedProcess(String error, Object... args) {
   }
 
   @Override
-  public void failedProcess(Exception cause) {
+  public void failedProcess(@Nonnull Exception cause) {
     observer.run();
 
     tracker.failedProcess(cause);
@@ -271,7 +271,8 @@ public void failedProcess(Exception cause) {
   }
 
   @Override
-  public void startingStage(String description, int workItems, FailurePolicy onFailure) {
+  public void startingStage(
+      @Nonnull String description, int workItems, @Nonnull FailurePolicy onFailure) {
     observer.run();
 
     if (isCancelled()) {
@@ -296,7 +297,7 @@ public void completedStage(String summary, Object... args) {
   }
 
   @Override
-  public void failedStage(String error, Object... args) {
+  public void failedStage(@Nonnull String error, Object... args) {
     observer.run();
 
     String message = format(error, args);
@@ -310,7 +311,7 @@ public void failedStage(String error, Object... args) {
   }
 
   @Override
-  public void failedStage(Exception cause) {
+  public void failedStage(@Nonnull Exception cause) {
     observer.run();
 
     cause = cancellationAsAbort(cause);
@@ -326,7 +327,7 @@ public void failedStage(Exception cause) {
   }
 
   @Override
-  public void startingWorkItem(String description, FailurePolicy onFailure) {
+  public void startingWorkItem(@Nonnull String description, @Nonnull FailurePolicy onFailure) {
     observer.run();
 
     tracker.startingWorkItem(description, onFailure);
@@ -346,7 +347,7 @@ public void completedWorkItem(String summary, Object... args) {
   }
 
   @Override
-  public void failedWorkItem(String error, Object... args) {
+  public void failedWorkItem(@Nonnull String error, Object... args) {
     observer.run();
 
     String message = format(error, args);
@@ -360,7 +361,7 @@ public void failedWorkItem(String error, Object... args) {
   }
 
   @Override
-  public void failedWorkItem(Exception cause) {
+  public void failedWorkItem(@Nonnull Exception cause) {
     observer.run();
 
     tracker.failedWorkItem(cause);