Java: more clear error message on generic class literal (IDEA-306263)

GitOrigin-RevId: d8d2cd5941a288e663fd6918c3e379b669553967

java/java-analysis-impl/src/com/intellij/codeInsight/daemon/impl/analysis/GenericsHighlightUtil.java

@@ -1061,8 +1061,16 @@ public final class GenericsHighlightUtil {
       return HighlightInfo.newHighlightInfo(HighlightInfoType.ERROR).range(operand).descriptionAndTooltip(description);
     }
     if (type.getParameters().length > 0) {
-      return HighlightInfo.newHighlightInfo(HighlightInfoType.ERROR).range(operand).descriptionAndTooltip(
-          JavaErrorBundle.message("cannot.select.from.parameterized.type"));
+      final HighlightInfo.Builder info = HighlightInfo.newHighlightInfo(HighlightInfoType.ERROR).range(operand).descriptionAndTooltip(
+        JavaErrorBundle.message("cannot.select.from.parameterized.type"));
+      final PsiJavaCodeReferenceElement referenceElement = operand.getInnermostComponentReferenceElement();
+      if (referenceElement != null) {
+        final PsiReferenceParameterList parameterList = referenceElement.getParameterList();
+        if (parameterList != null) {
+          info.registerFix(QUICK_FIX_FACTORY.createDeleteFix(parameterList), null, null, null, null);
+        }
+      }
+      return info;
     }
     return null;
   }

java/java-psi-impl/src/messages/JavaErrorBundle.properties

@@ -82,7 +82,7 @@ illegal.generic.type.for.instanceof=Illegal generic type for instanceof
 unsafe.cast.in.instanceof=''{0}'' cannot be safely cast to ''{1}''
 instanceof.pattern.supertype=Pattern type ''{0}'' is a supertype of expression type ''{1}''
 instanceof.pattern.equals=Pattern type ''{0}'' is the same as expression type
-cannot.select.dot.class.from.type.variable=Cannot select from a type variable
+cannot.select.dot.class.from.type.variable=Cannot access class object of a type parameter
 method.does.not.override.super=Method does not override method from its superclass
 static.method.cannot.be.annotated.with.override=Static methods cannot be annotated with @Override
 call.to.super.is.not.allowed.in.enum.constructor=Call to super is not allowed in enum constructor
@@ -518,7 +518,7 @@ qualified.class.reference.not.allowed.in.qualified.new=Qualified class reference
 actual.type.argument.contradict.inferred.type=Actual type argument and inferred type contradict each other
 default.method.overrides.object.member=Default method ''{0}'' overrides a member of ''java.lang.Object''
 two.methods.are.inherited.with.same.signature=Methods {0} from {1} and {2} from {3} are inherited with the same signature
-cannot.select.from.parameterized.type=Cannot select from parameterized type
+cannot.select.from.parameterized.type=Cannot access class object of parameterized type
 safevarargs.not.allowed.non.final.instance.methods=@SafeVarargs is not allowed on non-final instance methods
 safevarargs.not.suppress.potentially.unsafe.operations=@SafeVarargs do not suppress potentially unsafe operations
 safevarargs.not.applicable.for.reifiable.types=@SafeVarargs is not applicable for reifiable types

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/genericsHighlighting/IDEA57539.java

@@ -1,10 +1,10 @@
 class E<T> {
-    Class<T[]> o = <error descr="Cannot select from a type variable">T[]</error>.class;
+    Class<T[]> o = <error descr="Cannot access class object of a type parameter">T[]</error>.class;
 }
 
 class MyClass<T> {
     Class<T[]> getTs() {
-        return <error descr="Cannot select from a type variable">T[]</error>.class;
+        return <error descr="Cannot access class object of a type parameter">T[]</error>.class;
     }
 
     public static void main(String[] args) {

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/genericsHighlighting/ReferenceTypeParams.java

@@ -88,7 +88,7 @@ class myAList<T> extends mylist<T> {
 
   Class<T> foo (Class<T> clazz) {
         Class<String> clazz1 = (Class<String>)clazz;  //Should be unchecked warning
-        return <error descr="Cannot select from a type variable">T</error>.class;
+        return <error descr="Cannot access class object of a type parameter">T</error>.class;
   }
 }
 
@@ -130,11 +130,11 @@ abstract class GenericTest99<E extends Enum<E>> {
 
 class ClassLiteral<T> {
   {
-    Object c1 = <error descr="Cannot select from a type variable">T</error>.class;
-    Object c2 = <error descr="Cannot select from a type variable">T[]</error>.class;
+    Object c1 = <error descr="Cannot access class object of a type parameter">T</error>.class;
+    Object c2 = <error descr="Cannot access class object of a type parameter">T[]</error>.class;
     
-    Object c3 = <error descr="Cannot select from parameterized type">List<String></error>.class;
-    Object c4 = <error descr="Cannot select from parameterized type">List<String>[]</error>.class;
+    Object c3 = <error descr="Cannot access class object of parameterized type">List<String></error>.class;
+    Object c4 = <error descr="Cannot access class object of parameterized type">List<String>[]</error>.class;
     Object c5 = List[].class;
     Object c6 = List.class;
   }

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/genericsHighlighting8/IDEA57539.java

@@ -1,10 +1,10 @@
 class E<T> {
-    Class<T[]> o = <error descr="Cannot select from a type variable">T[]</error>.class;
+    Class<T[]> o = <error descr="Cannot access class object of a type parameter">T[]</error>.class;
 }
 
 class MyClass<T> {
     Class<T[]> getTs() {
-        return <error descr="Cannot select from a type variable">T[]</error>.class;
+        return <error descr="Cannot access class object of a type parameter">T[]</error>.class;
     }
 
     public static void main(String[] args) {

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/genericsHighlighting8/ReferenceTypeParams.java

@@ -88,7 +88,7 @@ class myAList<T> extends mylist<T> {
 
   Class<T> foo (Class<T> clazz) {
         Class<String> clazz1 = (Class<String>)clazz;  //Should be unchecked warning
-        return <error descr="Cannot select from a type variable">T</error>.class;
+        return <error descr="Cannot access class object of a type parameter">T</error>.class;
   }
 }
 
@@ -130,11 +130,11 @@ abstract class GenericTest99<E extends Enum<E>> {
 
 class ClassLiteral<T> {
   {
-    Object c1 = <error descr="Cannot select from a type variable">T</error>.class;
-    Object c2 = <error descr="Cannot select from a type variable">T[]</error>.class;
+    Object c1 = <error descr="Cannot access class object of a type parameter">T</error>.class;
+    Object c2 = <error descr="Cannot access class object of a type parameter">T[]</error>.class;
     
-    Object c3 = <error descr="Cannot select from parameterized type">List<String></error>.class;
-    Object c4 = <error descr="Cannot select from parameterized type">List<String>[]</error>.class;
+    Object c3 = <error descr="Cannot access class object of parameterized type">List<String></error>.class;
+    Object c4 = <error descr="Cannot access class object of parameterized type">List<String>[]</error>.class;
     Object c5 = List[].class;
     Object c6 = List.class;
   }