@Nullable
 public static List<? extends PsiElement> getAllPsiElements(final LookupElement item) {
   List<PsiMethod> allMethods = getAllMethods(item);
   if (allMethods != null) return allMethods;
   if (item.getObject() instanceof PsiElement)
     return Collections.singletonList((PsiElement) item.getObject());
   return null;
 }
  public static boolean insertTail(
      InsertionContext context, LookupElement item, TailType tailType, boolean hasTail) {
    TailType toInsert = tailType;
    LookupItem<?> lookupItem = item.as(LookupItem.CLASS_CONDITION_KEY);
    if (lookupItem == null
        || lookupItem.getAttribute(LookupItem.TAIL_TYPE_ATTR) != TailType.UNKNOWN) {
      if (!hasTail
          && item.getObject() instanceof PsiMethod
          && ((PsiMethod) item.getObject()).getReturnType() == PsiType.VOID) {
        PsiDocumentManager.getInstance(context.getProject()).commitAllDocuments();
        if (psiElement()
            .beforeLeaf(psiElement().withText("."))
            .accepts(context.getFile().findElementAt(context.getTailOffset() - 1))) {
          return false;
        }

        boolean insertAdditionalSemicolon = true;
        final PsiReferenceExpression referenceExpression =
            PsiTreeUtil.getTopmostParentOfType(
                context.getFile().findElementAt(context.getStartOffset()),
                PsiReferenceExpression.class);
        if (referenceExpression instanceof PsiMethodReferenceExpression
            && LambdaHighlightingUtil.insertSemicolon(referenceExpression.getParent())) {
          insertAdditionalSemicolon = false;
        } else if (referenceExpression != null) {
          PsiElement parent = referenceExpression.getParent();
          if (parent instanceof PsiMethodCallExpression) {
            parent = parent.getParent();
          }
          if (parent instanceof PsiLambdaExpression
              && !LambdaHighlightingUtil.insertSemicolonAfter((PsiLambdaExpression) parent)) {
            insertAdditionalSemicolon = false;
          }
        }
        if (insertAdditionalSemicolon) {
          toInsert = TailType.SEMICOLON;
        }
      }
    }
    toInsert.processTail(context.getEditor(), context.getTailOffset());
    return true;
  }
  public static List<PsiMethod> getAllMethods(LookupElement item) {
    List<SmartPsiElementPointer<PsiMethod>> pointers = item.getUserData(ALL_METHODS_ATTRIBUTE);
    if (pointers == null) return null;

    return ContainerUtil.mapNotNull(
        pointers,
        new Function<SmartPsiElementPointer<PsiMethod>, PsiMethod>() {
          @Override
          public PsiMethod fun(SmartPsiElementPointer<PsiMethod> pointer) {
            return pointer.getElement();
          }
        });
  }
 public static void putAllMethods(LookupElement item, List<PsiMethod> methods) {
   item.putUserData(
       ALL_METHODS_ATTRIBUTE,
       ContainerUtil.map(
           methods,
           new Function<PsiMethod, SmartPsiElementPointer<PsiMethod>>() {
             @Override
             public SmartPsiElementPointer<PsiMethod> fun(PsiMethod method) {
               return SmartPointerManager.getInstance(method.getProject())
                   .createSmartPsiElementPointer(method);
             }
           }));
 }
  public static void insertParentheses(
      final InsertionContext context,
      final LookupElement item,
      boolean overloadsMatter,
      boolean hasParams,
      final boolean forceClosingParenthesis) {
    final Editor editor = context.getEditor();
    final char completionChar = context.getCompletionChar();
    final PsiFile file = context.getFile();

    final TailType tailType =
        completionChar == '('
            ? TailType.NONE
            : completionChar == ':'
                ? TailType.COND_EXPR_COLON
                : LookupItem.handleCompletionChar(context.getEditor(), item, completionChar);
    final boolean hasTail = tailType != TailType.NONE && tailType != TailType.UNKNOWN;
    final boolean smart = completionChar == Lookup.COMPLETE_STATEMENT_SELECT_CHAR;

    if (completionChar == '('
        || completionChar == '.'
        || completionChar == ','
        || completionChar == ';'
        || completionChar == ':'
        || completionChar == ' ') {
      context.setAddCompletionChar(false);
    }

    if (hasTail) {
      hasParams = false;
    }
    final boolean needRightParenth =
        forceClosingParenthesis
            || !smart
                && (CodeInsightSettings.getInstance().AUTOINSERT_PAIR_BRACKET
                    || !hasParams && completionChar != '(');

    context.commitDocument();

    final CommonCodeStyleSettings styleSettings = context.getCodeStyleSettings();
    final PsiElement elementAt = file.findElementAt(context.getStartOffset());
    if (elementAt == null || !(elementAt.getParent() instanceof PsiMethodReferenceExpression)) {
      ParenthesesInsertHandler.getInstance(
              hasParams,
              styleSettings.SPACE_BEFORE_METHOD_CALL_PARENTHESES,
              styleSettings.SPACE_WITHIN_METHOD_CALL_PARENTHESES && hasParams,
              needRightParenth,
              styleSettings.METHOD_PARAMETERS_LPAREN_ON_NEXT_LINE)
          .handleInsert(context, item);
    }

    if (hasParams) {
      // Invoke parameters popup
      AutoPopupController.getInstance(file.getProject())
          .autoPopupParameterInfo(editor, overloadsMatter ? null : (PsiElement) item.getObject());
    }

    if (smart || !needRightParenth || !insertTail(context, item, tailType, hasTail)) {
      return;
    }

    if (completionChar == '.') {
      AutoPopupController.getInstance(file.getProject())
          .autoPopupMemberLookup(context.getEditor(), null);
    } else if (completionChar == ',') {
      AutoPopupController.getInstance(file.getProject())
          .autoPopupParameterInfo(context.getEditor(), null);
    }
  }
  @NotNull
  private static LookupElement castQualifier(
      @NotNull LookupElement item,
      @Nullable final PsiTypeLookupItem castTypeItem,
      @Nullable PsiType plainQualifier,
      JavaCompletionProcessor processor) {
    if (castTypeItem == null) {
      return item;
    }
    if (plainQualifier != null) {
      Object o = item.getObject();
      if (o instanceof PsiMethod) {
        PsiType castType = castTypeItem.getType();
        if (plainQualifier instanceof PsiClassType && castType instanceof PsiClassType) {
          PsiMethod method = (PsiMethod) o;
          PsiClassType.ClassResolveResult plainResult =
              ((PsiClassType) plainQualifier).resolveGenerics();
          PsiClass plainClass = plainResult.getElement();
          if (plainClass != null && plainClass.findMethodBySignature(method, true) != null) {
            PsiClass castClass = ((PsiClassType) castType).resolveGenerics().getElement();

            if (castClass == null || !castClass.isInheritor(plainClass, true)) {
              return item;
            }

            PsiSubstitutor plainSub = plainResult.getSubstitutor();
            PsiSubstitutor castSub =
                TypeConversionUtil.getSuperClassSubstitutor(plainClass, (PsiClassType) castType);
            PsiType returnType = method.getReturnType();
            if (method.getSignature(plainSub).equals(method.getSignature(castSub))) {
              PsiType typeAfterCast = toRaw(castSub.substitute(returnType));
              PsiType typeDeclared = toRaw(plainSub.substitute(returnType));
              if (typeAfterCast != null
                  && typeDeclared != null
                  && typeAfterCast.isAssignableFrom(typeDeclared)
                  && processor.isAccessible(plainClass.findMethodBySignature(method, true))) {
                return item;
              }
            }
          }
        }
      } else if (containsMember(plainQualifier, o)) {
        return item;
      }
    }

    return LookupElementDecorator.withInsertHandler(
        item,
        new InsertHandlerDecorator<LookupElement>() {
          @Override
          public void handleInsert(
              InsertionContext context, LookupElementDecorator<LookupElement> item) {
            final Document document = context.getEditor().getDocument();
            context.commitDocument();
            final PsiFile file = context.getFile();
            final PsiJavaCodeReferenceElement ref =
                PsiTreeUtil.findElementOfClassAtOffset(
                    file, context.getStartOffset(), PsiJavaCodeReferenceElement.class, false);
            if (ref != null) {
              final PsiElement qualifier = ref.getQualifier();
              if (qualifier != null) {
                final CommonCodeStyleSettings settings = context.getCodeStyleSettings();

                final String parenSpace = settings.SPACE_WITHIN_PARENTHESES ? " " : "";
                document.insertString(qualifier.getTextRange().getEndOffset(), parenSpace + ")");

                final String spaceWithin = settings.SPACE_WITHIN_CAST_PARENTHESES ? " " : "";
                final String prefix = "(" + parenSpace + "(" + spaceWithin;
                final String spaceAfter = settings.SPACE_AFTER_TYPE_CAST ? " " : "";
                final int exprStart = qualifier.getTextRange().getStartOffset();
                document.insertString(exprStart, prefix + spaceWithin + ")" + spaceAfter);

                CompletionUtil.emulateInsertion(context, exprStart + prefix.length(), castTypeItem);
                PsiDocumentManager.getInstance(file.getProject())
                    .doPostponedOperationsAndUnblockDocument(document);
                context.getEditor().getCaretModel().moveToOffset(context.getTailOffset());
              }
            }

            item.getDelegate().handleInsert(context);
          }
        });
  }
  public static Set<LookupElement> processJavaReference(
      PsiElement element,
      PsiJavaReference javaReference,
      ElementFilter elementFilter,
      JavaCompletionProcessor.Options options,
      final PrefixMatcher matcher,
      CompletionParameters parameters) {
    final Set<LookupElement> set = new LinkedHashSet<LookupElement>();
    final Condition<String> nameCondition =
        new Condition<String>() {
          @Override
          public boolean value(String s) {
            return matcher.prefixMatches(s);
          }
        };

    PsiMethodCallExpression call =
        PsiTreeUtil.getParentOfType(element, PsiMethodCallExpression.class);
    boolean checkInitialized =
        parameters.getInvocationCount() <= 1
            && call != null
            && PsiKeyword.SUPER.equals(call.getMethodExpression().getText());

    final JavaCompletionProcessor processor =
        new JavaCompletionProcessor(
            element, elementFilter, options.withInitialized(checkInitialized), nameCondition);
    final PsiType plainQualifier = processor.getQualifierType();
    PsiType qualifierType = plainQualifier;

    PsiType runtimeQualifier = getQualifierCastType(javaReference, parameters);
    if (runtimeQualifier != null) {
      PsiType composite =
          qualifierType == null
              ? runtimeQualifier
              : PsiIntersectionType.createIntersection(qualifierType, runtimeQualifier);
      PsiElement ctx = createContextWithXxxVariable(element, composite);
      javaReference =
          (PsiReferenceExpression)
              JavaPsiFacade.getElementFactory(element.getProject())
                  .createExpressionFromText("xxx.xxx", ctx);
      qualifierType = runtimeQualifier;
      processor.setQualifierType(qualifierType);
    }

    javaReference.processVariants(processor);

    final PsiTypeLookupItem castItem =
        runtimeQualifier == null
            ? null
            : PsiTypeLookupItem.createLookupItem(
                runtimeQualifier, (PsiReferenceExpression) javaReference);

    final boolean pkgContext = inSomePackage(element);

    final Set<PsiMember> mentioned = new THashSet<PsiMember>();
    for (CompletionElement completionElement : processor.getResults()) {
      for (LookupElement item : createLookupElements(completionElement, javaReference)) {
        item.putUserData(QUALIFIER_TYPE_ATTR, qualifierType);
        final Object o = item.getObject();
        if (o instanceof PsiClass && !isSourceLevelAccessible(element, (PsiClass) o, pkgContext)) {
          continue;
        }
        if (o instanceof PsiMember) {
          if (isInExcludedPackage((PsiMember) o, true)) {
            continue;
          }
          mentioned.add(CompletionUtil.getOriginalOrSelf((PsiMember) o));
        }
        set.add(
            highlightIfNeeded(
                qualifierType,
                castQualifier(item, castItem, plainQualifier, processor),
                o,
                element));
      }
    }

    if (javaReference instanceof PsiJavaCodeReferenceElement
        && !((PsiJavaCodeReferenceElement) javaReference).isQualified()) {
      final StaticMemberProcessor memberProcessor = new JavaStaticMemberProcessor(parameters);
      memberProcessor.processMembersOfRegisteredClasses(
          matcher,
          new PairConsumer<PsiMember, PsiClass>() {
            @Override
            public void consume(PsiMember member, PsiClass psiClass) {
              if (!mentioned.contains(member)
                  && processor.satisfies(member, ResolveState.initial())) {
                set.add(memberProcessor.createLookupElement(member, psiClass, true));
              }
            }
          });
    }

    return set;
  }
 @Nullable
 public static PsiType getLookupElementType(final LookupElement element) {
   TypedLookupItem typed = element.as(TypedLookupItem.CLASS_CONDITION_KEY);
   return typed != null ? typed.getType() : null;
 }
 public static PsiType getQualifierType(LookupElement item) {
   return item.getUserData(QUALIFIER_TYPE_ATTR);
 }