From da216bfcb953d5364a15f48e9ceda879e941998c Mon Sep 17 00:00:00 2001
From: peter <peter@jetbrains.com>
Date: Wed, 7 Sep 2016 12:19:04 +0200
Subject: [PATCH] reindex all java-like files on source root change
 (https://intellij-support.jetbrains.com/hc/en-us/community/posts/208569305-Cannot-find-classes-after-change-branches)

---
 .../openapi/roots/impl/JavaLanguageLevelPusher.java    | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/java/java-impl/src/com/intellij/openapi/roots/impl/JavaLanguageLevelPusher.java b/java/java-impl/src/com/intellij/openapi/roots/impl/JavaLanguageLevelPusher.java
index 8d0d8a80fb57..2dad1e391173 100644
--- a/java/java-impl/src/com/intellij/openapi/roots/impl/JavaLanguageLevelPusher.java
+++ b/java/java-impl/src/com/intellij/openapi/roots/impl/JavaLanguageLevelPusher.java
@@ -15,7 +15,9 @@
  */
 package com.intellij.openapi.roots.impl;
 
-import com.intellij.openapi.fileTypes.StdFileTypes;
+import com.intellij.lang.java.JavaLanguage;
+import com.intellij.openapi.fileTypes.FileType;
+import com.intellij.openapi.fileTypes.LanguageFileType;
 import com.intellij.openapi.module.EffectiveLanguageLevelUtil;
 import com.intellij.openapi.module.Module;
 import com.intellij.openapi.project.Project;
@@ -103,12 +105,16 @@ public class JavaLanguageLevelPusher implements FilePropertyPusher<LanguageLevel
     oStream.close();
 
     for (VirtualFile child : fileOrDir.getChildren()) {
-      if (!child.isDirectory() && StdFileTypes.JAVA.equals(child.getFileType())) {
+      if (!child.isDirectory() && isJavaLike(child.getFileType())) {
         PushedFilePropertiesUpdater.getInstance(project).filePropertiesChanged(child);
       }
     }
   }
 
+  private static boolean isJavaLike(FileType type) {
+    return type instanceof LanguageFileType && ((LanguageFileType)type).getLanguage().isKindOf(JavaLanguage.INSTANCE);
+  }
+
   @Override
   public void afterRootsChanged(@NotNull Project project) {
   }