From 7cdd6b1cbe4527fd353666b8baeb355083eb05e8 Mon Sep 17 00:00:00 2001
From: Bartek Pacia <bartek.pacia@jetbrains.com>
Date: Fri, 19 Dec 2025 13:18:31 +0100
Subject: [PATCH] LSP-345 fix ClassCastException when formatting a Java file
 with comments

The formatting code (AbstractJavaBlock#createJavaBlock) was using the deprecated InjectedLanguageUtil#hasInjections,
which internally cast InjectedLanguageManager to InjectedLanguageManagerImpl.
This failed in environments using CoreInjectedLanguageManager instead of InjectedLanguageManagerImpl, like the LSP.

I replaced the usage of InjectedLanguageUtil#hasInjections with `injectedLanguageManager.getInjectedPsiFiles() != null`
(just like the Javadoc of InjectedLanguageUtil#hasInjections suggests).

The root issue is that InjectedLanguageUtilBase#probeElementsUpInner calls InjectedLanguageManagerImpl#getInstanceImpl,
which in an antipattern: dependency on a specific implementation instead of the public interface.

GitOrigin-RevId: 1474f0d2a26800e8d49e0ea2bcd7b8da6d5cd83c
---
 .../psi/formatter/java/AbstractJavaBlock.java        | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/java/java-frontback-impl/src/com/intellij/psi/formatter/java/AbstractJavaBlock.java b/java/java-frontback-impl/src/com/intellij/psi/formatter/java/AbstractJavaBlock.java
index 83d4306f37fc..267932578055 100644
--- a/java/java-frontback-impl/src/com/intellij/psi/formatter/java/AbstractJavaBlock.java
+++ b/java/java-frontback-impl/src/com/intellij/psi/formatter/java/AbstractJavaBlock.java
@@ -4,6 +4,7 @@ package com.intellij.psi.formatter.java;
 import com.intellij.formatting.*;
 import com.intellij.formatting.alignment.AlignmentStrategy;
 import com.intellij.lang.ASTNode;
+import com.intellij.lang.injection.InjectedLanguageManager;
 import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.util.TextRange;
 import com.intellij.openapi.util.text.StringUtil;
@@ -16,7 +17,6 @@ import com.intellij.psi.formatter.java.wrap.ReservedWrapsProvider;
 import com.intellij.psi.impl.source.SourceTreeToPsiMap;
 import com.intellij.psi.impl.source.codeStyle.ShiftIndentInsideHelper;
 import com.intellij.psi.impl.source.tree.*;
-import com.intellij.psi.impl.source.tree.injected.InjectedLanguageUtil;
 import com.intellij.psi.impl.source.tree.java.ClassElement;
 import com.intellij.psi.javadoc.PsiMarkdownCodeBlock;
 import com.intellij.psi.jsp.JspClassLevelDeclarationStatementType;
@@ -198,11 +198,11 @@ public abstract class AbstractJavaBlock extends AbstractBlock implements JavaBlo
     if (isStatement(child, child.getTreeParent())) {
       return new CodeBlockBlock(child, wrap, alignment, actualIndent, settings, javaSettings, myFormattingMode);
     }
-    if (!isBuildIndentsOnly() &&
-        child instanceof PsiComment &&
-        child instanceof PsiLanguageInjectionHost &&
-        InjectedLanguageUtil.hasInjections((PsiLanguageInjectionHost)child)) {
-      return new CommentWithInjectionBlock(child, wrap, alignment, indent, settings, javaSettings, formattingMode);
+    if (!isBuildIndentsOnly() && child instanceof PsiComment && child instanceof PsiLanguageInjectionHost psiLanguageInjectionHost) {
+      InjectedLanguageManager injectedLanguageManager = InjectedLanguageManager.getInstance(childPsi.getProject());
+      if (injectedLanguageManager.getInjectedPsiFiles(psiLanguageInjectionHost) != null) {
+        return new CommentWithInjectionBlock(child, wrap, alignment, indent, settings, javaSettings, formattingMode);
+      }
     }
     if (child instanceof LeafElement || child instanceof PsiMarkdownCodeBlock) {
       if (child.getElementType() == JavaTokenType.C_STYLE_COMMENT) {