java: IdeJavaFoldingBuilderBase on frontend (part of java folding builder which doesn't depend on resolve) IJPL-185110

GitOrigin-RevId: 1932afe8a0a18e0a475d047461bf5e158761e35a

java/java-frontback-impl/resource/intellij.java.frontback.impl.xml

@@ -64,6 +64,9 @@
 
     <lang.lineWrapStrategy language="JAVA" implementationClass="com.intellij.psi.formatter.java.JavaLineWrapPositionStrategy"/>
 
+    <applicationService serviceInterface="com.intellij.codeInsight.folding.JavaCodeFoldingSettings"
+                        serviceImplementation="com.intellij.codeInsight.folding.impl.JavaCodeFoldingSettingsImpl"/>
+
     <registryKey key="java.formatter.chained.calls.pre212.compatibility"
                  defaultValue="false"
                  description="Format chained calls as in versions prior to 2021.2"/>

java/java-frontback-impl/src/com/intellij/codeInsight/folding/impl/IdeJavaFoldingBuilderBase.kt

@@ -0,0 +1,33 @@
+// 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.codeInsight.folding.impl
+
+import com.intellij.lang.java.JavaLanguage
+import com.intellij.openapi.editor.colors.EditorColors
+import com.intellij.openapi.editor.ex.util.EditorUtil
+import com.intellij.psi.*
+import com.intellij.psi.codeStyle.CodeStyleSettings
+import org.jetbrains.annotations.ApiStatus
+
+@ApiStatus.Internal
+open class IdeJavaFoldingBuilderBase: JavaFoldingBuilderBase() {
+  override fun isBelowRightMargin(file: PsiFile, lineLength: Int): Boolean {
+    val settings: CodeStyleSettings = com.intellij.application.options.CodeStyle.getSettings(file)
+    return lineLength <= settings.getRightMargin(JavaLanguage.INSTANCE)
+  }
+
+  protected open override fun shouldShowExplicitLambdaType(anonymousClass: PsiAnonymousClass, expression: PsiNewExpression): Boolean {
+    val parent = expression.getParent()
+    return parent is PsiReferenceExpression || parent is PsiAssignmentExpression
+  }
+
+  protected override fun rightArrow(): String {
+    return getRightArrow()
+  }
+
+  companion object {
+    @JvmStatic
+    fun getRightArrow(): String {
+      return EditorUtil.displayCharInEditor('\u2192', EditorColors.FOLDED_TEXT_ATTRIBUTES, "->")
+    }
+  }
+}

java/java-impl/resources/META-INF/JavaPlugin.xml

@@ -400,8 +400,6 @@
     <applicationService
       serviceInterface="com.intellij.codeInsight.generation.OverrideImplementExploreUtil$MemberImplementorExplorersProvider"
       serviceImplementation="com.intellij.codeInsight.generation.MemberImplementorExplorersProviderImpl"/>
-    <applicationService serviceInterface="com.intellij.codeInsight.folding.JavaCodeFoldingSettings"
-                        serviceImplementation="com.intellij.codeInsight.folding.impl.JavaCodeFoldingSettingsImpl"/>
     <applicationService serviceInterface="com.intellij.psi.CommonReferenceProviderTypes"
                         serviceImplementation="com.intellij.psi.impl.CommonReferenceProviderTypesImpl"/>
     <applicationService serviceInterface="com.intellij.psi.impl.file.PsiPackageImplementationHelper"

java/java-impl/src/com/intellij/codeInsight/folding/impl/JavaFoldingBuilder.java

@@ -1,41 +1,20 @@
 // 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.codeInsight.folding.impl;
 
-import com.intellij.application.options.CodeStyle;
 import com.intellij.codeInsight.ExpectedTypeInfo;
 import com.intellij.codeInsight.ExpectedTypesProvider;
-import com.intellij.lang.java.JavaLanguage;
-import com.intellij.openapi.editor.colors.EditorColors;
-import com.intellij.openapi.editor.ex.util.EditorUtil;
-import com.intellij.psi.*;
-import com.intellij.psi.codeStyle.CodeStyleSettings;
+import com.intellij.psi.PsiAnonymousClass;
+import com.intellij.psi.PsiNewExpression;
 import org.jetbrains.annotations.NotNull;
 
-public final class JavaFoldingBuilder extends JavaFoldingBuilderBase {
-  @Override
-  protected boolean isBelowRightMargin(@NotNull PsiFile file, int lineLength) {
-    final CodeStyleSettings settings = CodeStyle.getSettings(file);
-    return lineLength <= settings.getRightMargin(JavaLanguage.INSTANCE);
-  }
-
+public final class JavaFoldingBuilder extends IdeJavaFoldingBuilderBase {
   @Override
   protected boolean shouldShowExplicitLambdaType(@NotNull PsiAnonymousClass anonymousClass, @NotNull PsiNewExpression expression) {
-    PsiElement parent = expression.getParent();
-    if (parent instanceof PsiReferenceExpression || parent instanceof PsiAssignmentExpression) {
+    if (super.shouldShowExplicitLambdaType(anonymousClass, expression)) {
       return true;
     }
-
     ExpectedTypeInfo[] types = ExpectedTypesProvider.getExpectedTypes(expression, false);
     return types.length != 1 || !types[0].getType().equals(anonymousClass.getBaseClassType());
   }
-
-  @Override
-  protected @NotNull String rightArrow() {
-    return getRightArrow();
-  }
-
-  public static @NotNull String getRightArrow() {
-    return EditorUtil.displayCharInEditor('\u2192', EditorColors.FOLDED_TEXT_ATTRIBUTES, "->");
-  }
 }