@NotNull
 public XPathType getExpectedType(XPathExpression expr) {
   final XmlTag tag = PsiTreeUtil.getContextOfType(expr, XmlTag.class, true);
   if (tag != null && XsltSupport.isXsltTag(tag)) {
     final XsltElement element =
         XsltElementFactory.getInstance().wrapElement(tag, XsltElement.class);
     if (element instanceof XsltVariable) {
       return ((XsltVariable) element).getType();
     } else {
       final XmlAttribute attr = PsiTreeUtil.getContextOfType(expr, XmlAttribute.class, true);
       if (attr != null) {
         if (element instanceof XsltWithParam) {
           final XmlAttribute nameAttr = tag.getAttribute("name", null);
           if (nameAttr != null) {
             final XmlAttributeValue valueElement = nameAttr.getValueElement();
             if (valueElement != null) {
               final PsiReference[] references = valueElement.getReferences();
               for (PsiReference reference : references) {
                 final PsiElement psiElement = reference.resolve();
                 if (psiElement instanceof XsltVariable) {
                   return ((XsltVariable) psiElement).getType();
                 }
               }
             }
           }
         } else {
           final String name = attr.getName();
           return getTypeForTag(tag, name);
         }
       }
     }
   }
   return XPathType.UNKNOWN;
 }
  protected boolean preprocessUsages(Ref<UsageInfo[]> refUsages) {
    final MultiMap<PsiElement, String> conflicts = new MultiMap<PsiElement, String>();

    checkExistingMethods(conflicts, true);
    checkExistingMethods(conflicts, false);
    final Collection<PsiClass> classes = ClassInheritorsSearch.search(myClass).findAll();
    for (FieldDescriptor fieldDescriptor : myFieldDescriptors) {
      final Set<PsiMethod> setters = new HashSet<PsiMethod>();
      final Set<PsiMethod> getters = new HashSet<PsiMethod>();

      for (PsiClass aClass : classes) {
        final PsiMethod getterOverrider =
            myDescriptor.isToEncapsulateGet()
                ? aClass.findMethodBySignature(fieldDescriptor.getGetterPrototype(), false)
                : null;
        if (getterOverrider != null) {
          getters.add(getterOverrider);
        }
        final PsiMethod setterOverrider =
            myDescriptor.isToEncapsulateSet()
                ? aClass.findMethodBySignature(fieldDescriptor.getSetterPrototype(), false)
                : null;
        if (setterOverrider != null) {
          setters.add(setterOverrider);
        }
      }
      if (!getters.isEmpty() || !setters.isEmpty()) {
        final PsiField field = fieldDescriptor.getField();
        for (PsiReference reference : ReferencesSearch.search(field)) {
          final PsiElement place = reference.getElement();
          if (place instanceof PsiReferenceExpression) {
            final PsiExpression qualifierExpression =
                ((PsiReferenceExpression) place).getQualifierExpression();
            final PsiClass ancestor;
            if (qualifierExpression == null) {
              ancestor = PsiTreeUtil.getParentOfType(place, PsiClass.class, false);
            } else {
              ancestor = PsiUtil.resolveClassInType(qualifierExpression.getType());
            }

            final boolean isGetter = !PsiUtil.isAccessedForWriting((PsiExpression) place);
            for (PsiMethod overridden : isGetter ? getters : setters) {
              if (InheritanceUtil.isInheritorOrSelf(myClass, ancestor, true)) {
                conflicts.putValue(
                    overridden,
                    "There is already a "
                        + RefactoringUIUtil.getDescription(overridden, true)
                        + " which would hide generated "
                        + (isGetter ? "getter" : "setter")
                        + " for "
                        + place.getText());
                break;
              }
            }
          }
        }
      }
    }
    return showConflicts(conflicts, refUsages.get());
  }
  @Override
  public boolean processUsage(
      ChangeInfo changeInfo, UsageInfo usageInfo, boolean beforeMethodChange, UsageInfo[] usages) {
    if (!(changeInfo instanceof JavaChangeInfo)) return false;

    PsiElement element = usageInfo.getElement();
    if (element == null) return false;
    if (!GroovyLanguage.INSTANCE.equals(element.getLanguage())) return false;

    if (beforeMethodChange) {
      if (usageInfo instanceof OverriderUsageInfo) {
        processPrimaryMethodInner(
            ((JavaChangeInfo) changeInfo),
            (GrMethod) ((OverriderUsageInfo) usageInfo).getElement(),
            ((OverriderUsageInfo) usageInfo).getBaseMethod());
      }
    } else {
      if (usageInfo instanceof GrMethodCallUsageInfo) {
        processMethodUsage(
            element,
            ((JavaChangeInfo) changeInfo),
            ((GrMethodCallUsageInfo) usageInfo).isToChangeArguments(),
            ((GrMethodCallUsageInfo) usageInfo).isToCatchExceptions(),
            ((GrMethodCallUsageInfo) usageInfo).getMapToArguments(),
            ((GrMethodCallUsageInfo) usageInfo).getSubstitutor());
        return true;
      } else if (usageInfo instanceof DefaultConstructorImplicitUsageInfo) {
        processConstructor(
            (GrMethod) ((DefaultConstructorImplicitUsageInfo) usageInfo).getConstructor(),
            (JavaChangeInfo) changeInfo);
        return true;
      } else if (usageInfo instanceof NoConstructorClassUsageInfo) {
        processClassUsage(
            (GrTypeDefinition) ((NoConstructorClassUsageInfo) usageInfo).getPsiClass(),
            ((JavaChangeInfo) changeInfo));
        return true;
      } else if (usageInfo instanceof ChangeSignatureParameterUsageInfo) {
        String newName = ((ChangeSignatureParameterUsageInfo) usageInfo).newParameterName;
        ((PsiReference) element).handleElementRename(newName);
        return true;
      } else {
        PsiReference ref = element.getReference();
        if (ref != null && changeInfo.getMethod() != null) {
          ref.bindToElement(changeInfo.getMethod());
          return true;
        }
      }
    }
    return false;
  }
 @Nullable
 static PsiElement resolveReference(final PsiReference psiReference) {
   if (psiReference instanceof PsiPolyVariantReference) {
     final ResolveResult[] results = ((PsiPolyVariantReference) psiReference).multiResolve(true);
     if (results.length == 1) return results[0].getElement();
   }
   return psiReference.resolve();
 }
  // need to shorten references in type argument list
  public static void shortenReference(final PsiFile file, final int offset)
      throws IncorrectOperationException {
    Project project = file.getProject();
    final PsiDocumentManager manager = PsiDocumentManager.getInstance(project);
    Document document = manager.getDocument(file);
    if (document == null) {
      PsiUtilCore.ensureValid(file);
      LOG.error("No document for " + file);
      return;
    }

    manager.commitDocument(document);
    final PsiReference ref = file.findReferenceAt(offset);
    if (ref != null) {
      PsiElement element = ref.getElement();
      if (element != null) {
        JavaCodeStyleManager.getInstance(project).shortenClassReferences(element);
        PsiDocumentManager.getInstance(project).doPostponedOperationsAndUnblockDocument(document);
      }
    }
  }
  @NotNull
  protected UsageInfo[] findUsages() {
    ArrayList<EncapsulateFieldUsageInfo> array = ContainerUtil.newArrayList();
    for (FieldDescriptor fieldDescriptor : myFieldDescriptors) {
      for (final PsiReference reference : ReferencesSearch.search(fieldDescriptor.getField())) {
        final PsiElement element = reference.getElement();
        if (element == null) continue;

        final EncapsulateFieldHelper helper =
            EncapsulateFieldHelper.getHelper(element.getLanguage());
        if (helper != null) {
          EncapsulateFieldUsageInfo usageInfo =
              helper.createUsage(myDescriptor, fieldDescriptor, reference);
          if (usageInfo != null) {
            array.add(usageInfo);
          }
        }
      }
    }
    EncapsulateFieldUsageInfo[] usageInfos =
        array.toArray(new EncapsulateFieldUsageInfo[array.size()]);
    return UsageViewUtil.removeDuplicatedUsages(usageInfos);
  }
  private void checkExistingMethods(MultiMap<PsiElement, String> conflicts, boolean isGetter) {
    if (isGetter) {
      if (!myDescriptor.isToEncapsulateGet()) return;
    } else {
      if (!myDescriptor.isToEncapsulateSet()) return;
    }

    for (FieldDescriptor descriptor : myFieldDescriptors) {
      PsiMethod prototype =
          isGetter ? descriptor.getGetterPrototype() : descriptor.getSetterPrototype();

      final PsiType prototypeReturnType = prototype.getReturnType();
      PsiMethod existing = myClass.findMethodBySignature(prototype, true);
      if (existing != null) {
        final PsiType returnType = existing.getReturnType();
        if (!RefactoringUtil.equivalentTypes(
            prototypeReturnType, returnType, myClass.getManager())) {
          final String descr =
              PsiFormatUtil.formatMethod(
                  existing,
                  PsiSubstitutor.EMPTY,
                  PsiFormatUtilBase.SHOW_NAME
                      | PsiFormatUtilBase.SHOW_PARAMETERS
                      | PsiFormatUtilBase.SHOW_TYPE,
                  PsiFormatUtilBase.SHOW_TYPE);
          String message =
              isGetter
                  ? RefactoringBundle.message(
                      "encapsulate.fields.getter.exists",
                      CommonRefactoringUtil.htmlEmphasize(descr),
                      CommonRefactoringUtil.htmlEmphasize(prototype.getName()))
                  : RefactoringBundle.message(
                      "encapsulate.fields.setter.exists",
                      CommonRefactoringUtil.htmlEmphasize(descr),
                      CommonRefactoringUtil.htmlEmphasize(prototype.getName()));
          conflicts.putValue(existing, message);
        }
      } else {
        PsiClass containingClass = myClass.getContainingClass();
        while (containingClass != null && existing == null) {
          existing = containingClass.findMethodBySignature(prototype, true);
          if (existing != null) {
            for (PsiReference reference : ReferencesSearch.search(existing)) {
              final PsiElement place = reference.getElement();
              LOG.assertTrue(place instanceof PsiReferenceExpression);
              final PsiExpression qualifierExpression =
                  ((PsiReferenceExpression) place).getQualifierExpression();
              final PsiClass inheritor;
              if (qualifierExpression == null) {
                inheritor = PsiTreeUtil.getParentOfType(place, PsiClass.class, false);
              } else {
                inheritor = PsiUtil.resolveClassInType(qualifierExpression.getType());
              }

              if (InheritanceUtil.isInheritorOrSelf(inheritor, myClass, true)) {
                conflicts.putValue(
                    existing,
                    "There is already a "
                        + RefactoringUIUtil.getDescription(existing, true)
                        + " which would be hidden by generated "
                        + (isGetter ? "getter" : "setter"));
                break;
              }
            }
          }
          containingClass = containingClass.getContainingClass();
        }
      }
    }
  }
  public boolean processUsage(
      ChangeInfo changeInfo, UsageInfo usage, boolean beforeMethodChange, UsageInfo[] usages) {
    if (!isJavaUsage(usage)) return false;
    if (!(changeInfo instanceof JavaChangeInfo)) return false;

    if (beforeMethodChange) {
      if (usage instanceof CallerUsageInfo) {
        final CallerUsageInfo callerUsageInfo = (CallerUsageInfo) usage;
        processCallerMethod(
            (JavaChangeInfo) changeInfo,
            callerUsageInfo.getMethod(),
            null,
            callerUsageInfo.isToInsertParameter(),
            callerUsageInfo.isToInsertException());
        return true;
      } else if (usage instanceof OverriderUsageInfo) {
        OverriderUsageInfo info = (OverriderUsageInfo) usage;
        final PsiMethod method = info.getElement();
        final PsiMethod baseMethod = info.getBaseMethod();
        if (info.isOriginalOverrider()) {
          processPrimaryMethod((JavaChangeInfo) changeInfo, method, baseMethod, false);
        } else {
          processCallerMethod(
              (JavaChangeInfo) changeInfo,
              method,
              baseMethod,
              info.isToInsertArgs(),
              info.isToCatchExceptions());
        }
        return true;
      }

    } else {
      PsiElement element = usage.getElement();
      LOG.assertTrue(element != null);

      if (usage instanceof DefaultConstructorImplicitUsageInfo) {
        final DefaultConstructorImplicitUsageInfo defConstructorUsage =
            (DefaultConstructorImplicitUsageInfo) usage;
        PsiMethod constructor = defConstructorUsage.getConstructor();
        if (!constructor.isPhysical()) {
          final boolean toPropagate =
              changeInfo instanceof JavaChangeInfoImpl
                  && ((JavaChangeInfoImpl) changeInfo)
                      .propagateParametersMethods.remove(constructor);
          final PsiClass containingClass = defConstructorUsage.getContainingClass();
          constructor = (PsiMethod) containingClass.add(constructor);
          PsiUtil.setModifierProperty(
              constructor,
              VisibilityUtil.getVisibilityModifier(containingClass.getModifierList()),
              true);
          if (toPropagate) {
            ((JavaChangeInfoImpl) changeInfo).propagateParametersMethods.add(constructor);
          }
        }
        addSuperCall(
            (JavaChangeInfo) changeInfo,
            constructor,
            defConstructorUsage.getBaseConstructor(),
            usages);
        return true;
      } else if (usage instanceof NoConstructorClassUsageInfo) {
        addDefaultConstructor(
            ((JavaChangeInfo) changeInfo),
            ((NoConstructorClassUsageInfo) usage).getPsiClass(),
            usages);
        return true;
      } else if (usage instanceof MethodCallUsageInfo) {
        final MethodCallUsageInfo methodCallInfo = (MethodCallUsageInfo) usage;
        processMethodUsage(
            methodCallInfo.getElement(),
            (JavaChangeInfo) changeInfo,
            methodCallInfo.isToChangeArguments(),
            methodCallInfo.isToCatchExceptions(),
            methodCallInfo.getReferencedMethod(),
            methodCallInfo.getSubstitutor(),
            usages);
        return true;
      } else if (usage instanceof ChangeSignatureParameterUsageInfo) {
        String newName = ((ChangeSignatureParameterUsageInfo) usage).newParameterName;
        String oldName = ((ChangeSignatureParameterUsageInfo) usage).oldParameterName;
        processParameterUsage((PsiReferenceExpression) element, oldName, newName);
        return true;
      } else if (usage instanceof CallReferenceUsageInfo) {
        ((CallReferenceUsageInfo) usage).getReference().handleChangeSignature(changeInfo);
        return true;
      } else if (element instanceof PsiEnumConstant) {
        fixActualArgumentsList(
            ((PsiEnumConstant) element).getArgumentList(),
            (JavaChangeInfo) changeInfo,
            true,
            PsiSubstitutor.EMPTY);
        return true;
      } else if (!(usage instanceof OverriderUsageInfo)) {
        PsiReference reference =
            usage instanceof MoveRenameUsageInfo ? usage.getReference() : element.getReference();
        if (reference != null) {
          PsiElement target = changeInfo.getMethod();
          if (target != null) {
            reference.bindToElement(target);
          }
        }
      }
    }
    return false;
  }
  public static int insertClassReference(
      PsiClass psiClass, PsiFile file, int startOffset, int endOffset) {
    final Project project = file.getProject();
    PsiDocumentManager documentManager = PsiDocumentManager.getInstance(project);
    documentManager.commitAllDocuments();

    final PsiManager manager = file.getManager();

    final Document document =
        FileDocumentManager.getInstance().getDocument(file.getViewProvider().getVirtualFile());

    final PsiReference reference = file.findReferenceAt(startOffset);
    if (reference != null) {
      final PsiElement resolved = reference.resolve();
      if (resolved instanceof PsiClass) {
        if (((PsiClass) resolved).getQualifiedName() == null
            || manager.areElementsEquivalent(psiClass, resolved)) {
          return endOffset;
        }
      }
    }

    String name = psiClass.getName();
    if (name == null) {
      return endOffset;
    }

    assert document != null;
    document.replaceString(startOffset, endOffset, name);

    int newEndOffset = startOffset + name.length();
    final RangeMarker toDelete = insertTemporary(newEndOffset, document, " ");

    documentManager.commitAllDocuments();

    PsiElement element = file.findElementAt(startOffset);
    if (element instanceof PsiIdentifier) {
      PsiElement parent = element.getParent();
      if (parent instanceof PsiJavaCodeReferenceElement
          && !((PsiJavaCodeReferenceElement) parent).isQualified()
          && !(parent.getParent() instanceof PsiPackageStatement)) {
        PsiJavaCodeReferenceElement ref = (PsiJavaCodeReferenceElement) parent;

        if (psiClass.isValid()
            && !psiClass.getManager().areElementsEquivalent(psiClass, resolveReference(ref))) {
          final boolean staticImport = ref instanceof PsiImportStaticReferenceElement;
          PsiElement newElement;
          try {
            newElement =
                staticImport
                    ? ((PsiImportStaticReferenceElement) ref).bindToTargetClass(psiClass)
                    : ref.bindToElement(psiClass);
          } catch (IncorrectOperationException e) {
            return endOffset; // can happen if fqn contains reserved words, for example
          }

          final RangeMarker rangeMarker = document.createRangeMarker(newElement.getTextRange());
          documentManager.doPostponedOperationsAndUnblockDocument(document);
          documentManager.commitDocument(document);

          newElement =
              CodeInsightUtilCore.findElementInRange(
                  file,
                  rangeMarker.getStartOffset(),
                  rangeMarker.getEndOffset(),
                  PsiJavaCodeReferenceElement.class,
                  JavaLanguage.INSTANCE);
          rangeMarker.dispose();
          if (newElement != null) {
            newEndOffset = newElement.getTextRange().getEndOffset();
            if (!(newElement instanceof PsiReferenceExpression)) {
              PsiReferenceParameterList parameterList =
                  ((PsiJavaCodeReferenceElement) newElement).getParameterList();
              if (parameterList != null) {
                newEndOffset = parameterList.getTextRange().getStartOffset();
              }
            }

            if (!staticImport
                && !psiClass
                    .getManager()
                    .areElementsEquivalent(psiClass, resolveReference((PsiReference) newElement))
                && !PsiUtil.isInnerClass(psiClass)) {
              final String qName = psiClass.getQualifiedName();
              if (qName != null) {
                document.replaceString(
                    newElement.getTextRange().getStartOffset(), newEndOffset, qName);
                newEndOffset = newElement.getTextRange().getStartOffset() + qName.length();
              }
            }
          }
        }
      }
    }

    if (toDelete.isValid()) {
      document.deleteString(toDelete.getStartOffset(), toDelete.getEndOffset());
    }

    return newEndOffset;
  }