How to use

getPackage

method

in

com.intellij.psi.JavaDirectoryService

PsiPackage aPackage = directory == null ? null : JavaDirectoryService.getInstance().getPackage(directory);
if (aPackage == memberPackage || aPackage != null && memberPackage != null && Comparing.strEqual(aPackage.getQualifiedName(), memberPackage.getQualifiedName())) {
 return suggestPackageLocal(member);

  @Override
  protected void run(@NotNull Result<PsiFile> result) throws Throwable {
    final PsiPackage packageElement = directoryService.getPackage(directory);
    if (packageElement == null) {
      throw new InvalidDirectoryException("Target directory does not provide a package");
    }

    final String fileName = Extensions.append(name, StdFileTypes.JAVA);
    final PsiFile found = directory.findFile(fileName);
    if (found != null) {
      throw new ClassAlreadyExistsException("Class '" + name + "'already exists in " + packageElement.getName());
    }

    final String packageName = packageElement.getQualifiedName();
    final String className = Extensions.remove(this.name, StdFileTypes.JAVA);
    try {
      final String java = converter.convert(packageName, className, json);
      final PsiFile classFile = fileFactory.createFileFromText(fileName, JavaFileType.INSTANCE, java);
      CodeStyleManager.getInstance(classFile.getProject()).reformat(classFile);
      JavaCodeStyleManager.getInstance(classFile.getProject()).optimizeImports(classFile);
      final PsiFile created = (PsiFile) directory.add(classFile);
      result.setResult(created);
    } catch (IOException e) {
      throw new ClassCreationException("Failed to create new class from JSON", e);
    }
  }
}

 @Override
 protected void run() throws Throwable {
  try {
   PsiDirectory psiDirectory = PsiManager.getInstance(project).findDirectory(virtualFile.getParent());
   assert psiDirectory != null;
   PsiPackage aPackage = JavaDirectoryService.getInstance().getPackage(psiDirectory);
   String packageName = aPackage == null ? null : aPackage.getQualifiedName();
   String text = generateLexerText(bnfFile, packageName);
   VfsUtil.saveText(virtualFile, text);
   Notifications.Bus.notify(new Notification(BnfConstants.GENERATION_GROUP,
     virtualFile.getName() + " generated", "to " + virtualFile.getParent().getPath(),
     NotificationType.INFORMATION), project);
   associateFileTypeAndNavigate(project, virtualFile);
  }
  catch (final IncorrectOperationException e) {
   ApplicationManager.getApplication().invokeLater(
    () -> Messages.showErrorDialog(project, "Unable to create file " + flexFileName + "\n" + e.getLocalizedMessage(), "Create JFlex Lexer"));
  }
 }
}.execute();

PsiPackage memberPackage = memberDirectory == null ? null : JavaDirectoryService.getInstance().getPackage(memberDirectory);
log(member.getName()+ ": checking effective level for "+member);