Introduce SubTask.getOwnerExecutable

core/src/main/java/hudson/model/Queue.java

@@ -2077,10 +2077,14 @@ public interface Executable extends Runnable {
 
         /**
          * An umbrella executable (such as a {@link Run}) of which this is one part.
-         * If {@link #getParent} has a distinct {@link SubTask#getOwnerTask},
-         * then it should be the case that {@code getParentExecutable().getParent() == getParent().getOwnerTask()}.
+         * Some invariants:
+         * <ul>
+         * <li>{@code getParent().getOwnerTask() == getParent() || getParentExecutable().getParent() == getParent().getOwnerTask()}
+         * <li>{@code getParent().getOwnerExecutable() == null || getParentExecutable() == getParent().getOwnerExecutable()}
+         * </ul>
          * @return a <em>distinct</em> executable (never {@code this}, unlike the default of {@link SubTask#getOwnerTask}!); or null if this executable was already at top level
          * @since 2.313, but implementations can already implement this with a lower core dependency.
+         * @see SubTask#getOwnerExecutable
          */
         default @CheckForNull Executable getParentExecutable() {
             return null;

core/src/main/java/hudson/model/queue/SubTask.java

@@ -30,15 +30,14 @@
 import hudson.model.Executor;
 import hudson.model.Label;
 import hudson.model.Node;
-import hudson.model.Queue.Executable;
-import hudson.model.Queue.Task;
+import hudson.model.Queue;
 import hudson.model.ResourceActivity;
 import java.io.IOException;
 
 /**
- * A component of {@link Task} that represents a computation carried out by a single {@link Executor}.
+ * A component of {@link Queue.Task} that represents a computation carried out by a single {@link Executor}.
  *
- * A {@link Task} consists of a number of {@link SubTask}.
+ * A {@link Queue.Task} consists of a number of {@link SubTask}.
  *
  * <p>
  * Plugins are encouraged to extend from {@link AbstractSubTask}
@@ -79,23 +78,34 @@ default long getEstimatedDuration() {
     }
 
     /**
-     * Creates {@link Executable}, which performs the actual execution of the task.
-     * @return {@link Executable} to be launched or null if the executable cannot be
+     * Creates an object which performs the actual execution of the task.
+     * @return executable to be launched or null if the executable cannot be
      * created (e.g. {@link AbstractProject} is disabled)
-     * @exception IOException {@link Executable} cannot be created
+     * @exception IOException executable cannot be created
      */
-    @CheckForNull Executable createExecutable() throws IOException;
+    @CheckForNull Queue.Executable createExecutable() throws IOException;
 
     /**
-     * Gets the {@link Task} that this subtask belongs to.
+     * Gets the task that this subtask belongs to.
      * @return by default, {@code this}
+     * @see #getOwnerExecutable
      */
-    default @NonNull Task getOwnerTask() {
-        return (Task) this;
+    default @NonNull Queue.Task getOwnerTask() {
+        return (Queue.Task) this;
     }
 
     /**
-     * If a subset of {@link SubTask}s of a {@link Task} needs to be collocated with other {@link SubTask}s,
+     * If this task is associated with an executable of {@link #getOwnerTask}, finds that.
+     * @return by default, {@code null}
+     * @see hudson.model.Queue.Executable#getParentExecutable
+     * @since TODO
+     */
+    default @CheckForNull Queue.Executable getOwnerExecutable() {
+        return null;
+    }
+
+    /**
+     * If a subset of {@link SubTask}s of a {@link Queue.Task} needs to be collocated with other {@link SubTask}s,
      * those {@link SubTask}s should return the equal object here. If null, the execution unit isn't under a
      * colocation constraint.
      * @return by default, null