[refactoring] IJPL-3459: (followup) replace .isShutdownHookRunning() with .isShutdownStarted()

+ make ShutDownTracker internal

GitOrigin-RevId: e6954bf75e2e7b91436684b15eb96ea1798a2745

platform/core-impl/src/com/intellij/openapi/editor/impl/DocumentImpl.java

@@ -1,4 +1,4 @@
-// Copyright 2000-2023 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.openapi.editor.impl;
 
 import com.intellij.core.CoreBundle;
@@ -875,7 +875,7 @@ public final class DocumentImpl extends UserDataHolderBase implements DocumentEx
 
     getLineSet(); // initialize line set to track changed lines
 
-    if (!ShutDownTracker.isShutdownHookRunning()) {
+    if (!ShutDownTracker.isShutdownStarted()) {
       DocumentListener[] listeners = getListeners();
       ProgressManager.getInstance().executeNonCancelableSection(() -> {
         for (int i = listeners.length - 1; i >= 0; i--) {
@@ -916,7 +916,7 @@ public final class DocumentImpl extends UserDataHolderBase implements DocumentEx
       myFrozen = null;
       setModificationStamp(newModificationStamp);
 
-      if (!ShutDownTracker.isShutdownHookRunning()) {
+      if (!ShutDownTracker.isShutdownStarted()) {
         DocumentListener[] listeners = getListeners();
         ProgressManager.getInstance().executeNonCancelableSection(() -> {
           for (DocumentListener listener : listeners) {

platform/platform-impl/src/com/intellij/openapi/editor/impl/TrailingSpacesStripper.java

@@ -229,7 +229,7 @@ public final class TrailingSpacesStripper implements FileDocumentManagerListener
     boolean markAsNeedsStrippingLater = ((DocumentImpl)document)
       .stripTrailingSpaces(getProject(document, activeEditors), inChangedLinesOnly, skipCaretLines ? caretOffsets : null);
 
-    if (!activeEditors.isEmpty() && !ShutDownTracker.isShutdownHookRunning()) {
+    if (!activeEditors.isEmpty() && !ShutDownTracker.isShutdownStarted()) {
       runBatchCaretOperation(activeEditors, () -> {
         for (int i = 0; i < carets.size(); i++) {
           Caret caret = carets.get(i);

platform/platform-impl/src/com/intellij/openapi/vfs/impl/local/NativeFileWatcherImpl.java

@@ -177,7 +177,7 @@ public class NativeFileWatcherImpl extends PluggableFileWatcher {
     if (myIsShuttingDown) {
       return;
     }
-    if (ShutDownTracker.isShutdownHookRunning()) {
+    if (ShutDownTracker.isShutdownStarted()) {
       myIsShuttingDown = true;
       return;
     }

platform/util/api-dump-unreviewed.txt

@@ -1087,12 +1087,6 @@ com.intellij.openapi.util.ScalableIcon
 - javax.swing.Icon
 - a:getScale():F
 - a:scale(F):javax.swing.Icon
-f:com.intellij.openapi.util.ShutDownTracker
-- s:getInstance():com.intellij.openapi.util.ShutDownTracker
-- s:isShutdownHookRunning():Z
-- registerShutdownTask(java.lang.Runnable):V
-- unregisterShutdownTask(java.lang.Runnable):V
-- waitFor(J,java.util.concurrent.TimeUnit):Z
 a:com.intellij.openapi.util.SimpleFieldCache
 - com.intellij.openapi.util.FieldCache
 - <init>():V

platform/util/src/com/intellij/openapi/util/ShutDownTracker.java

@@ -32,6 +32,7 @@ import java.util.concurrent.TimeUnit;
  * regular ways of resource management there possible.
  * </p>
  */
+@ApiStatus.Internal
 public final class ShutDownTracker {
   private final Deque<Runnable> myShutdownTasks = new ConcurrentLinkedDeque<>();
   private final Deque<Runnable> myCachesShutdownTasks = new ConcurrentLinkedDeque<>();
@@ -50,12 +51,15 @@ public final class ShutDownTracker {
     return ShutDownTrackerHolder.ourInstance;
   }
 
-  //FIXME RC: many clients use that method, even though it is unreliable: thread.isAlive is true only while
-  // hook thread is running, it becomes false as soon as the thread finishes -- but clients use this method
-  // to ask 'is shutdown _initiated_' so they expect it to return true from that moment and until app actually
-  // terminates. shutdownSequenceIsStarted fits better for that goal
+  /** @deprecated use {@link #isShutdownStarted()} -- more correct and explicit */
+  @Deprecated
   public static boolean isShutdownHookRunning() {
-    return getInstance().myThread.isAlive();
+    return isShutdownStarted();
+  }
+
+  /** @return true if shutdown hook is started -- no more tasks could be added after that */
+  public static boolean isShutdownStarted() {
+    return getInstance().shutdownSequenceIsStarted;
   }
 
   /** true if shutdown thread is started: no shutdown tasks could be added after that */
@@ -91,16 +95,16 @@ public final class ShutDownTracker {
   }
 
   /**
-   * FIXME RC: method terminates immediately if shutdown thread is not started yet (!isAlive) -- which makes
-   * its use unreliable, since you can't be sure the thread is already started, and without it the method
-   * could terminate immediately while hook is not even started
-   *
-   * Waits for shutdown tasks termination up to specified amount of time.
+   * If shutdown is started -- waits for shutdown tasks termination, up to specified amount of time.
+   * <p>
+   * <b>BEWARE</b>: method terminates immediately if shutdown thread is not started yet (!isAlive) -- which
+   * makes its use unreliable, since you can't be sure the thread is already started, and without that the
+   * method could terminate immediately while hook is not even started.
    *
    * @return true if terminated inside given timeout
    */
   public boolean waitFor(long timeout, @NotNull TimeUnit unit) {
-    if (isShutdownHookRunning()) {
+    if (myThread.isAlive()) {
       try {
         myThread.join(unit.toMillis(timeout));
       }