suggest import for non-accessible classes (IDEA-192084)

assuming that no accessible classes are available and non-accessible classes are located inside the project so the visibility could be changed

java/java-impl/src/com/intellij/codeInsight/daemon/impl/quickfix/ImportClassFix.java

@@ -107,6 +107,7 @@ public class ImportClassFix extends ImportClassFixBase<PsiJavaCodeReferenceEleme
 
   @Override
   protected boolean canReferenceClass(PsiJavaCodeReferenceElement ref) {
+    if (PsiTreeUtil.getParentOfType(ref, PsiImportStatementBase.class) != null) return false;
     if (ref instanceof PsiReferenceExpression) {
       PsiElement parent = ref.getParent();
       return parent instanceof PsiReferenceExpression || parent instanceof PsiExpressionStatement;

java/java-impl/src/com/intellij/codeInsight/daemon/impl/quickfix/ImportClassFixBase.java

@@ -121,13 +121,15 @@ public abstract class ImportClassFixBase<T extends PsiElement, R extends PsiRefe
       if (qName != null) { //filter local classes
         if (qName.indexOf('.') == -1 || !PsiNameHelper.getInstance(project).isQualifiedName(qName)) continue; //do not show classes from default or invalid package
         if (qName.endsWith(name) && (file == null || ImportFilter.shouldImport(file, qName))) {
-          if (isAccessible(aClass, myElement)) {
-            classList.add(aClass);
-          }
+          classList.add(aClass);
         }
       }
     }
 
+    boolean anyAccessibleFound = classList.stream().anyMatch(aClass -> isAccessible(aClass, myElement));
+    PsiManager manager = myElement.getManager();
+    classList.removeIf(aClass -> (anyAccessibleFound || !manager.isInProject(aClass)) && !isAccessible(aClass, myElement));
+
     if (acceptWrongNumberOfTypeParams && referenceHasTypeParameters) {
       final List<PsiClass> candidates = new ArrayList<>();
       for (Iterator<PsiClass> iterator = classList.iterator(); iterator.hasNext(); ) {

java/java-tests/testSrc/com/intellij/java/codeInsight/intention/AddImportActionTest.groovy

@@ -670,4 +670,14 @@ class Foo {
 '''
     assert myFixture.filterAvailableIntentions("Import class").empty
   }
+
+  void "test inaccessible class from the project"() {
+    myFixture.addClass('package foo; class Foo {}')
+    myFixture.configureByText 'a.java', '''
+class Bar {
+  F<caret>oo abc;
+}  
+'''
+    assert !myFixture.filterAvailableIntentions("Import class").empty
+  }
 }