[ByteCodeViewer] IDEA-375222 Update tab name when tabs are closed

Current problems:
- does not respect the application-wide "Show directory for non-unique file names" setting

GitOrigin-RevId: 8b68558206017503fad07a55f0e3505ba3f73da9

plugins/ByteCodeViewer/src/com/intellij/byteCodeViewer/BytecodeToolWindowService.kt

@@ -0,0 +1,91 @@
+// Copyright 2000-2025 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+package com.intellij.byteCodeViewer
+
+import com.intellij.openapi.components.Service
+import com.intellij.openapi.project.Project
+import com.intellij.openapi.util.Disposer
+import com.intellij.openapi.vfs.VfsUtil
+import com.intellij.openapi.wm.ToolWindow
+import com.intellij.ui.content.Content
+import com.intellij.ui.content.ContentManagerEvent
+import com.intellij.ui.content.ContentManagerListener
+import java.util.concurrent.ConcurrentHashMap
+
+/**
+ * Ensures that the [ContentManagerListener] is registered only once
+ * and properly unregistered when the project is disposed.
+ */
+@Service(Service.Level.PROJECT)
+class BytecodeToolWindowService(private val project: Project) {
+  private val registeredListeners = ConcurrentHashMap<ToolWindow, ContentManagerListener>()
+
+  /**
+   * Registers a ContentManagerListener for the BytecodeViewer tool window if not already registered.
+   * The listener is responsible for updating tab titles when tabs are added or removed.
+   *
+   * If the listener for a specific instance of [ToolWindow] is already registered, this is a no-op.
+   */
+  fun ensureContentManagerListenerRegistered(toolWindow: ToolWindow) {
+    val contentManager = toolWindow.contentManager
+
+    // Check if the listener is already registered
+    if (registeredListeners.containsKey(toolWindow)) {
+      return
+    }
+
+    val listener = object : ContentManagerListener {
+      override fun contentAdded(event: ContentManagerEvent) {
+        deduplicateTabNames(toolWindow)
+      }
+
+      override fun contentRemoved(event: ContentManagerEvent) {
+        deduplicateTabNames(toolWindow)
+      }
+    }
+    contentManager.addContentManagerListener(listener)
+    registeredListeners[toolWindow] = listener
+
+    Disposer.register(toolWindow.disposable) {
+      contentManager.removeContentManagerListener(listener)
+      registeredListeners.remove(toolWindow)
+    }
+  }
+
+  /**
+   * Updates tab titles to avoid duplicate names by adding path information when necessary.
+   */
+  fun deduplicateTabNames(toolWindow: ToolWindow) {
+    val titlesToContents = mutableMapOf<String, MutableList<Content>>()
+    for (content in toolWindow.contentManager.contents) {
+      val classFileName = content.getUserData(JAVA_CLASS_FILE)?.name
+                          ?: throw IllegalStateException("Content entry has no JAVA_CLASS_FILE or it is null. Entry: $content")
+      titlesToContents.getOrPut(classFileName) { mutableListOf() }.add(content)
+    }
+    for ((classFileName, contents) in titlesToContents) {
+      if (contents.size == 1) {
+        contents[0].displayName = classFileName
+      }
+      else if (contents.size > 1) {
+        val paths = contents.map {
+          it.getUserData(JAVA_CLASS_FILE) ?: throw IllegalStateException("No class file path for content entry $it")
+        }
+
+        val commonAncestor = VfsUtil.getCommonAncestor(paths) ?: continue
+
+        for (i in contents.indices) {
+          val content = contents[i]
+          content.displayName = VfsUtil.getRelativePath(
+            content.getUserData(JAVA_CLASS_FILE) ?: throw IllegalStateException("No class file path for content entry $content"),
+            commonAncestor,
+          )
+        }
+      }
+    }
+  }
+
+  companion object {
+    fun getInstance(project: Project): BytecodeToolWindowService {
+      return project.getService(BytecodeToolWindowService::class.java)
+    }
+  }
+}

plugins/ByteCodeViewer/src/com/intellij/byteCodeViewer/ShowBytecodeAction.kt

@@ -6,16 +6,12 @@ import com.intellij.notification.Notification
 import com.intellij.notification.NotificationType
 import com.intellij.openapi.actionSystem.*
 import com.intellij.openapi.util.Key
-import com.intellij.openapi.vfs.VfsUtil
 import com.intellij.openapi.vfs.VirtualFile
-import com.intellij.openapi.wm.ToolWindow
 import com.intellij.openapi.wm.ToolWindowAnchor
 import com.intellij.openapi.wm.ToolWindowManager
-import com.intellij.ui.content.Content
 import com.intellij.ui.content.ContentFactory
 
-private val JAVA_SOURCE_FILE = Key.create<VirtualFile>("JAVA_SOURCE_FILE")
-private val JAVA_CLASS_FILE = Key.create<VirtualFile>("JAVA_CLASS_FILE")
+internal val JAVA_CLASS_FILE = Key.create<VirtualFile>("JAVA_CLASS_FILE")
 
 internal class ShowBytecodeAction : AnAction() {
   override fun getActionUpdateThread(): ActionUpdateThread = ActionUpdateThread.BGT
@@ -35,6 +31,10 @@ internal class ShowBytecodeAction : AnAction() {
                        hideOnEmptyContent = true
                        canCloseContent = true
                      }
+    val service = BytecodeToolWindowService.getInstance(project)
+
+    service.ensureContentManagerListenerRegistered(toolWindow)
+
     val editor = event.getData(CommonDataKeys.EDITOR) ?: return
     val psiFile = event.getData(CommonDataKeys.PSI_FILE) ?: return
     val psiElement = psiFile.findElementAt(editor.caretModel.offset) ?: return
@@ -77,38 +77,13 @@ internal class ShowBytecodeAction : AnAction() {
 
 
     toolWindow.contentManager.addContent(content)
-    deduplicateTabNames(toolWindow)
+    service.deduplicateTabNames(toolWindow)
     content.setDisposer(panel)
     toolWindow.contentManager.setSelectedContent(content)
     toolWindow.setAdditionalGearActions(createActionGroup())
     toolWindow.activate(null)
   }
 
-  private fun deduplicateTabNames(toolWindow: ToolWindow) {
-    val titlesToContents = mutableMapOf<String, MutableList<Content>>()
-    for (contentEntry in toolWindow.contentManager.contents) {
-      val tabName = contentEntry.getUserData(JAVA_CLASS_FILE)?.name ?: throw IllegalStateException("No title for content entry $contentEntry")
-      titlesToContents.getOrPut(tabName) { mutableListOf() }.add(contentEntry)
-    }
-    for (contents in titlesToContents.values) {
-      if (contents.size > 1) {
-        val paths = contents.map {
-          it.getUserData(JAVA_CLASS_FILE) ?: throw IllegalStateException("No class file path for content entry $it")
-        }
-
-        val commonAncestor = VfsUtil.getCommonAncestor(paths) ?: continue
-
-        for (i in contents.indices) {
-          val content = contents[i]
-          content.displayName = VfsUtil.getRelativePath(
-            content.getUserData(JAVA_CLASS_FILE) ?: throw IllegalStateException("No class file path for content entry $content"),
-            commonAncestor,
-          )
-        }
-      }
-    }
-  }
-
   private fun createActionGroup(): ActionGroup {
     val action = object : ToggleAction(BytecodeViewerBundle.messagePointer("action.show.debug.action.name")) {
       override fun getActionUpdateThread(): ActionUpdateThread = ActionUpdateThread.EDT