diff --git a/java/debugger/impl/src/com/intellij/debugger/memory/ui/ClassesFilteredView.java b/java/debugger/impl/src/com/intellij/debugger/memory/ui/ClassesFilteredView.java
index b9dfc3a4dd35..8078423e8040 100644
--- a/java/debugger/impl/src/com/intellij/debugger/memory/ui/ClassesFilteredView.java
+++ b/java/debugger/impl/src/com/intellij/debugger/memory/ui/ClassesFilteredView.java
@@ -253,12 +253,9 @@ public class ClassesFilteredView extends BorderLayoutPanel implements Disposable
     myDebugSessionListener = new MyDebuggerSessionListener();
     debugSession.addSessionListener(myDebugSessionListener, this);
 
-    mySingleAlarm = new SingleAlarmWithMutableDelay(() -> {
-      final SuspendContextImpl suspendContext = debugProcess.getDebuggerContext().getSuspendContext();
-      if (suspendContext != null) {
-        ApplicationManager.getApplication().invokeLater(() -> myTable.setBusy(true));
-        managerThread.schedule(new MyUpdateClassesCommand(suspendContext));
-      }
+    mySingleAlarm = new SingleAlarmWithMutableDelay(suspendContext -> {
+      ApplicationManager.getApplication().invokeLater(() -> myTable.setBusy(true));
+      suspendContext.getDebugProcess().getManagerThread().schedule(new MyUpdateClassesCommand(suspendContext));
     }, this);
 
     mySingleAlarm.setDelay((int)TimeUnit.MILLISECONDS.toMillis(500));
@@ -336,8 +333,12 @@ public class ClassesFilteredView extends BorderLayoutPanel implements Disposable
       if (debugSession != null) {
         final DebugProcess debugProcess = DebuggerManager.getInstance(myProject)
           .getDebugProcess(debugSession.getDebugProcess().getProcessHandler());
-        if (debugProcess != null && debugProcess.isAttached()) {
-          mySingleAlarm.cancelAndRequest();
+        if (debugProcess != null && debugProcess.isAttached() && debugProcess instanceof DebugProcessImpl) {
+          final DebugProcessImpl process = (DebugProcessImpl)debugProcess;
+          final SuspendContextImpl context = process.getDebuggerContext().getSuspendContext();
+          if (context != null) {
+            mySingleAlarm.cancelAndRequest(context);
+          }
         }
       }
     }, x -> myProject.isDisposed());
diff --git a/java/debugger/impl/src/com/intellij/debugger/memory/utils/SingleAlarmWithMutableDelay.java b/java/debugger/impl/src/com/intellij/debugger/memory/utils/SingleAlarmWithMutableDelay.java
index 879b46d8ec90..036ba7faf904 100644
--- a/java/debugger/impl/src/com/intellij/debugger/memory/utils/SingleAlarmWithMutableDelay.java
+++ b/java/debugger/impl/src/com/intellij/debugger/memory/utils/SingleAlarmWithMutableDelay.java
@@ -15,16 +15,19 @@
  */
 package com.intellij.debugger.memory.utils;
 
+import com.intellij.debugger.engine.SuspendContextImpl;
 import com.intellij.openapi.Disposable;
 import com.intellij.util.Alarm;
 import org.jetbrains.annotations.NotNull;
 
-public class SingleAlarmWithMutableDelay extends Alarm {
-  private final Runnable myTask;
+public class SingleAlarmWithMutableDelay {
+  private final Alarm myAlarm;
+  private final Task myTask;
+
   private volatile int myDelayMillis;
 
-  public SingleAlarmWithMutableDelay(@NotNull Runnable task, @NotNull Disposable parentDisposable) {
-    super(ThreadToUse.POOLED_THREAD, parentDisposable);
+  public SingleAlarmWithMutableDelay(@NotNull Task task, @NotNull Disposable parentDisposable) {
+    myAlarm = new Alarm(Alarm.ThreadToUse.POOLED_THREAD, parentDisposable);
     myTask = task;
   }
 
@@ -32,10 +35,23 @@ public class SingleAlarmWithMutableDelay extends Alarm {
     myDelayMillis = millis;
   }
 
-  public void cancelAndRequest() {
-    if (!isDisposed()) {
+  public void cancelAndRequest(@NotNull SuspendContextImpl suspendContext) {
+    if (!myAlarm.isDisposed()) {
       cancelAllRequests();
-      addRequest(myTask, myDelayMillis);
+      addRequest(() -> myTask.run(suspendContext));
     }
   }
+
+  public void cancelAllRequests() {
+    myAlarm.cancelAllRequests();
+  }
+
+  private void addRequest(@NotNull Runnable runnable) {
+    myAlarm.addRequest(runnable, myDelayMillis);
+  }
+
+  @FunctionalInterface
+  public interface Task {
+    void run(@NotNull SuspendContextImpl suspendContext);
+  }
 }