@Nullable
 private String createListIterationText(@NotNull PsiForStatement forStatement) {
   final PsiBinaryExpression condition =
       (PsiBinaryExpression) ParenthesesUtils.stripParentheses(forStatement.getCondition());
   if (condition == null) {
     return null;
   }
   final PsiExpression lhs = ParenthesesUtils.stripParentheses(condition.getLOperand());
   if (lhs == null) {
     return null;
   }
   final PsiExpression rhs = ParenthesesUtils.stripParentheses(condition.getROperand());
   if (rhs == null) {
     return null;
   }
   final IElementType tokenType = condition.getOperationTokenType();
   final String indexName;
   PsiExpression collectionSize;
   if (JavaTokenType.LT.equals(tokenType)) {
     indexName = lhs.getText();
     collectionSize = rhs;
   } else if (JavaTokenType.GT.equals(tokenType)) {
     indexName = rhs.getText();
     collectionSize = lhs;
   } else {
     return null;
   }
   if (collectionSize instanceof PsiReferenceExpression) {
     final PsiReferenceExpression referenceExpression = (PsiReferenceExpression) collectionSize;
     final PsiElement target = referenceExpression.resolve();
     if (target instanceof PsiVariable) {
       final PsiVariable variable = (PsiVariable) target;
       collectionSize = ParenthesesUtils.stripParentheses(variable.getInitializer());
     }
   }
   if (!(collectionSize instanceof PsiMethodCallExpression)) {
     return null;
   }
   final PsiMethodCallExpression methodCallExpression =
       (PsiMethodCallExpression) ParenthesesUtils.stripParentheses(collectionSize);
   if (methodCallExpression == null) {
     return null;
   }
   final PsiReferenceExpression listLengthExpression =
       methodCallExpression.getMethodExpression();
   final PsiExpression qualifier =
       ParenthesesUtils.stripParentheses(listLengthExpression.getQualifierExpression());
   final PsiReferenceExpression listReference;
   if (qualifier instanceof PsiReferenceExpression) {
     listReference = (PsiReferenceExpression) qualifier;
   } else {
     listReference = null;
   }
   PsiType parameterType;
   if (listReference == null) {
     parameterType = extractListTypeFromContainingClass(forStatement);
   } else {
     final PsiType type = listReference.getType();
     if (type == null) {
       return null;
     }
     parameterType = extractContentTypeFromType(type);
   }
   if (parameterType == null) {
     parameterType = TypeUtils.getObjectType(forStatement);
   }
   final String typeString = parameterType.getCanonicalText();
   final PsiVariable listVariable;
   if (listReference == null) {
     listVariable = null;
   } else {
     final PsiElement target = listReference.resolve();
     if (!(target instanceof PsiVariable)) {
       return null;
     }
     listVariable = (PsiVariable) target;
   }
   final PsiStatement body = forStatement.getBody();
   final PsiStatement firstStatement = getFirstStatement(body);
   final boolean isDeclaration =
       isListElementDeclaration(firstStatement, listVariable, indexName, parameterType);
   final String contentVariableName;
   @NonNls final String finalString;
   final PsiStatement statementToSkip;
   if (isDeclaration) {
     final PsiDeclarationStatement declarationStatement =
         (PsiDeclarationStatement) firstStatement;
     assert declarationStatement != null;
     final PsiElement[] declaredElements = declarationStatement.getDeclaredElements();
     final PsiElement declaredElement = declaredElements[0];
     if (!(declaredElement instanceof PsiVariable)) {
       return null;
     }
     final PsiVariable variable = (PsiVariable) declaredElement;
     contentVariableName = variable.getName();
     statementToSkip = declarationStatement;
     if (variable.hasModifierProperty(PsiModifier.FINAL)) {
       finalString = "final ";
     } else {
       finalString = "";
     }
   } else {
     final String collectionName;
     if (listReference == null) {
       collectionName = null;
     } else {
       collectionName = listReference.getReferenceName();
     }
     contentVariableName = createNewVariableName(forStatement, parameterType, collectionName);
     finalString = "";
     statementToSkip = null;
   }
   @NonNls final StringBuilder out = new StringBuilder();
   out.append("for(");
   out.append(finalString);
   out.append(typeString);
   out.append(' ');
   out.append(contentVariableName);
   out.append(": ");
   @NonNls final String listName;
   if (listReference == null) {
     listName = "this";
   } else {
     listName = listReference.getText();
   }
   out.append(listName);
   out.append(')');
   if (body != null) {
     replaceCollectionGetAccess(
         body, contentVariableName, listVariable, indexName, statementToSkip, out);
   }
   return out.toString();
 }
 @Nullable
 private String createCollectionIterationText(@NotNull PsiForStatement forStatement)
     throws IncorrectOperationException {
   final PsiStatement body = forStatement.getBody();
   final PsiStatement firstStatement = getFirstStatement(body);
   final PsiStatement initialization = forStatement.getInitialization();
   if (!(initialization instanceof PsiDeclarationStatement)) {
     return null;
   }
   final PsiDeclarationStatement declaration = (PsiDeclarationStatement) initialization;
   final PsiElement declaredIterator = declaration.getDeclaredElements()[0];
   if (!(declaredIterator instanceof PsiVariable)) {
     return null;
   }
   final PsiVariable iteratorVariable = (PsiVariable) declaredIterator;
   final PsiMethodCallExpression initializer =
       (PsiMethodCallExpression) iteratorVariable.getInitializer();
   if (initializer == null) {
     return null;
   }
   final PsiType iteratorType = initializer.getType();
   if (iteratorType == null) {
     return null;
   }
   final PsiType iteratorContentType = extractContentTypeFromType(iteratorType);
   final PsiType iteratorVariableType = iteratorVariable.getType();
   final PsiType contentType;
   final PsiClassType javaLangObject = TypeUtils.getObjectType(forStatement);
   if (iteratorContentType == null) {
     final PsiType iteratorVariableContentType =
         extractContentTypeFromType(iteratorVariableType);
     if (iteratorVariableContentType == null) {
       contentType = javaLangObject;
     } else {
       contentType = iteratorVariableContentType;
     }
   } else {
     contentType = iteratorContentType;
   }
   final PsiReferenceExpression methodExpression = initializer.getMethodExpression();
   final PsiExpression collection = methodExpression.getQualifierExpression();
   final String iteratorName = iteratorVariable.getName();
   final boolean isDeclaration =
       isIteratorNextDeclaration(firstStatement, iteratorName, contentType);
   final PsiStatement statementToSkip;
   @NonNls final String finalString;
   final String contentVariableName;
   if (isDeclaration) {
     final PsiDeclarationStatement declarationStatement =
         (PsiDeclarationStatement) firstStatement;
     assert declarationStatement != null;
     final PsiElement[] declaredElements = declarationStatement.getDeclaredElements();
     final PsiElement declaredElement = declaredElements[0];
     if (!(declaredElement instanceof PsiVariable)) {
       return null;
     }
     final PsiVariable variable = (PsiVariable) declaredElement;
     contentVariableName = variable.getName();
     statementToSkip = declarationStatement;
     if (variable.hasModifierProperty(PsiModifier.FINAL)) {
       finalString = "final ";
     } else {
       finalString = "";
     }
   } else {
     if (collection instanceof PsiReferenceExpression) {
       final PsiReferenceExpression referenceExpression = (PsiReferenceExpression) collection;
       final String collectionName = referenceExpression.getReferenceName();
       contentVariableName = createNewVariableName(forStatement, contentType, collectionName);
     } else {
       contentVariableName = createNewVariableName(forStatement, contentType, null);
     }
     final Project project = forStatement.getProject();
     final CodeStyleSettings codeStyleSettings = CodeStyleSettingsManager.getSettings(project);
     if (codeStyleSettings.GENERATE_FINAL_LOCALS) {
       finalString = "final ";
     } else {
       finalString = "";
     }
     statementToSkip = null;
   }
   final String contentTypeString = contentType.getCanonicalText();
   @NonNls final StringBuilder out = new StringBuilder();
   out.append("for(");
   out.append(finalString);
   out.append(contentTypeString);
   out.append(' ');
   out.append(contentVariableName);
   out.append(": ");
   if (!contentType.equals(javaLangObject)) {
     @NonNls final String iterableTypeString = "java.lang.Iterable<" + contentTypeString + '>';
     if (iteratorContentType == null) {
       out.append('(');
       out.append(iterableTypeString);
       out.append(')');
     }
   }
   if (collection == null) {
     out.append("this");
   } else {
     out.append(collection.getText());
   }
   out.append(')');
   replaceIteratorNext(
       body, contentVariableName, iteratorName, statementToSkip, out, contentType);
   return out.toString();
 }
 @Nullable
 private String createArrayIterationText(@NotNull PsiForStatement forStatement) {
   final PsiExpression condition = forStatement.getCondition();
   final PsiBinaryExpression strippedCondition =
       (PsiBinaryExpression) ParenthesesUtils.stripParentheses(condition);
   if (strippedCondition == null) {
     return null;
   }
   final PsiExpression lhs = ParenthesesUtils.stripParentheses(strippedCondition.getLOperand());
   if (lhs == null) {
     return null;
   }
   final PsiExpression rhs = ParenthesesUtils.stripParentheses(strippedCondition.getROperand());
   if (rhs == null) {
     return null;
   }
   final IElementType tokenType = strippedCondition.getOperationTokenType();
   final PsiReferenceExpression arrayLengthExpression;
   final String indexName;
   if (tokenType.equals(JavaTokenType.LT)) {
     arrayLengthExpression = (PsiReferenceExpression) ParenthesesUtils.stripParentheses(rhs);
     indexName = lhs.getText();
   } else if (tokenType.equals(JavaTokenType.GT)) {
     arrayLengthExpression = (PsiReferenceExpression) ParenthesesUtils.stripParentheses(lhs);
     indexName = rhs.getText();
   } else {
     return null;
   }
   if (arrayLengthExpression == null) {
     return null;
   }
   PsiReferenceExpression arrayReference =
       (PsiReferenceExpression) arrayLengthExpression.getQualifierExpression();
   if (arrayReference == null) {
     final PsiElement target = arrayLengthExpression.resolve();
     if (!(target instanceof PsiVariable)) {
       return null;
     }
     final PsiVariable variable = (PsiVariable) target;
     final PsiExpression initializer = variable.getInitializer();
     if (!(initializer instanceof PsiReferenceExpression)) {
       return null;
     }
     final PsiReferenceExpression referenceExpression = (PsiReferenceExpression) initializer;
     arrayReference = (PsiReferenceExpression) referenceExpression.getQualifierExpression();
     if (arrayReference == null) {
       return null;
     }
   }
   final PsiType type = arrayReference.getType();
   if (!(type instanceof PsiArrayType)) {
     return null;
   }
   final PsiArrayType arrayType = (PsiArrayType) type;
   final PsiType componentType = arrayType.getComponentType();
   final String typeText = componentType.getCanonicalText();
   final PsiElement target = arrayReference.resolve();
   if (!(target instanceof PsiVariable)) {
     return null;
   }
   final PsiVariable arrayVariable = (PsiVariable) target;
   final PsiStatement body = forStatement.getBody();
   final PsiStatement firstStatement = getFirstStatement(body);
   final boolean isDeclaration =
       isArrayElementDeclaration(firstStatement, arrayVariable, indexName);
   final String contentVariableName;
   @NonNls final String finalString;
   final PsiStatement statementToSkip;
   if (isDeclaration) {
     final PsiDeclarationStatement declarationStatement =
         (PsiDeclarationStatement) firstStatement;
     assert declarationStatement != null;
     final PsiElement[] declaredElements = declarationStatement.getDeclaredElements();
     final PsiElement declaredElement = declaredElements[0];
     if (!(declaredElement instanceof PsiVariable)) {
       return null;
     }
     final PsiVariable variable = (PsiVariable) declaredElement;
     if (VariableAccessUtils.variableIsAssigned(variable, forStatement)) {
       final String collectionName = arrayReference.getReferenceName();
       contentVariableName = createNewVariableName(forStatement, componentType, collectionName);
       final Project project = forStatement.getProject();
       final CodeStyleSettings codeStyleSettings = CodeStyleSettingsManager.getSettings(project);
       if (codeStyleSettings.GENERATE_FINAL_LOCALS) {
         finalString = "final ";
       } else {
         finalString = "";
       }
       statementToSkip = null;
     } else {
       contentVariableName = variable.getName();
       statementToSkip = declarationStatement;
       if (variable.hasModifierProperty(PsiModifier.FINAL)) {
         finalString = "final ";
       } else {
         finalString = "";
       }
     }
   } else {
     final String collectionName = arrayReference.getReferenceName();
     contentVariableName = createNewVariableName(forStatement, componentType, collectionName);
     final Project project = forStatement.getProject();
     final CodeStyleSettings codeStyleSettings = CodeStyleSettingsManager.getSettings(project);
     if (codeStyleSettings.GENERATE_FINAL_LOCALS) {
       finalString = "final ";
     } else {
       finalString = "";
     }
     statementToSkip = null;
   }
   @NonNls final StringBuilder out = new StringBuilder();
   out.append("for(");
   out.append(finalString);
   out.append(typeText);
   out.append(' ');
   out.append(contentVariableName);
   out.append(": ");
   final String arrayName = arrayReference.getText();
   out.append(arrayName);
   out.append(')');
   if (body != null) {
     replaceArrayAccess(
         body, contentVariableName, arrayVariable, indexName, statementToSkip, out);
   }
   return out.toString();
 }
 private boolean checkCondition(
     @Nullable PsiExpression condition,
     @NotNull PsiStatement context,
     List<PsiExpression> notUpdated) {
   if (condition == null) {
     return false;
   }
   if (PsiUtil.isConstantExpression(condition) || PsiKeyword.NULL.equals(condition.getText())) {
     return true;
   }
   if (condition instanceof PsiInstanceOfExpression) {
     final PsiInstanceOfExpression instanceOfExpression = (PsiInstanceOfExpression) condition;
     final PsiExpression operand = instanceOfExpression.getOperand();
     return checkCondition(operand, context, notUpdated);
   } else if (condition instanceof PsiParenthesizedExpression) {
     // catch stuff like "while ((x)) { ... }"
     final PsiExpression expression = ((PsiParenthesizedExpression) condition).getExpression();
     return checkCondition(expression, context, notUpdated);
   } else if (condition instanceof PsiPolyadicExpression) {
     // while (value != x) { ... }
     // while (value != (x + y)) { ... }
     // while (b1 && b2) { ... }
     final PsiPolyadicExpression polyadicExpression = (PsiPolyadicExpression) condition;
     for (PsiExpression operand : polyadicExpression.getOperands()) {
       if (!checkCondition(operand, context, notUpdated)) {
         return false;
       }
     }
     return true;
   } else if (condition instanceof PsiReferenceExpression) {
     final PsiReferenceExpression referenceExpression = (PsiReferenceExpression) condition;
     final PsiElement element = referenceExpression.resolve();
     if (element instanceof PsiField) {
       final PsiField field = (PsiField) element;
       final PsiType type = field.getType();
       if (field.hasModifierProperty(PsiModifier.FINAL) && type.getArrayDimensions() == 0) {
         if (field.hasModifierProperty(PsiModifier.STATIC)) {
           return true;
         }
         final PsiExpression qualifier = referenceExpression.getQualifierExpression();
         if (qualifier == null) {
           return true;
         } else if (checkCondition(qualifier, context, notUpdated)) {
           return true;
         }
       }
     } else if (element instanceof PsiVariable) {
       final PsiVariable variable = (PsiVariable) element;
       if (variable.hasModifierProperty(PsiModifier.FINAL)) {
         // final variables cannot be updated, don't bother to
         // flag them
         return true;
       } else if (element instanceof PsiLocalVariable || element instanceof PsiParameter) {
         if (!VariableAccessUtils.variableIsAssigned(variable, context)) {
           notUpdated.add(referenceExpression);
           return true;
         }
       }
     }
   } else if (condition instanceof PsiPrefixExpression) {
     final PsiPrefixExpression prefixExpression = (PsiPrefixExpression) condition;
     final IElementType tokenType = prefixExpression.getOperationTokenType();
     if (JavaTokenType.EXCL.equals(tokenType)
         || JavaTokenType.PLUS.equals(tokenType)
         || JavaTokenType.MINUS.equals(tokenType)) {
       final PsiExpression operand = prefixExpression.getOperand();
       return checkCondition(operand, context, notUpdated);
     }
   } else if (condition instanceof PsiArrayAccessExpression) {
     // Actually the contents of the array could change nevertheless
     // if it is accessed through a different reference like this:
     //   int[] local_ints = new int[]{1, 2};
     //   int[] other_ints = local_ints;
     //   while (local_ints[0] > 0) { other_ints[0]--; }
     //
     // Keep this check?
     final PsiArrayAccessExpression accessExpression = (PsiArrayAccessExpression) condition;
     final PsiExpression indexExpression = accessExpression.getIndexExpression();
     return checkCondition(indexExpression, context, notUpdated)
         && checkCondition(accessExpression.getArrayExpression(), context, notUpdated);
   } else if (condition instanceof PsiConditionalExpression) {
     final PsiConditionalExpression conditionalExpression = (PsiConditionalExpression) condition;
     final PsiExpression thenExpression = conditionalExpression.getThenExpression();
     final PsiExpression elseExpression = conditionalExpression.getElseExpression();
     if (thenExpression == null || elseExpression == null) {
       return false;
     }
     return checkCondition(conditionalExpression.getCondition(), context, notUpdated)
         && checkCondition(thenExpression, context, notUpdated)
         && checkCondition(elseExpression, context, notUpdated);
   } else if (condition instanceof PsiThisExpression) {
     return true;
   } else if (condition instanceof PsiMethodCallExpression && !ignoreIterators) {
     final PsiMethodCallExpression methodCallExpression = (PsiMethodCallExpression) condition;
     if (!IteratorUtils.isCallToHasNext(methodCallExpression)) {
       return false;
     }
     final PsiReferenceExpression methodExpression = methodCallExpression.getMethodExpression();
     final PsiExpression qualifierExpression = methodExpression.getQualifierExpression();
     if (qualifierExpression instanceof PsiReferenceExpression) {
       final PsiReferenceExpression referenceExpression =
           (PsiReferenceExpression) qualifierExpression;
       final PsiElement element = referenceExpression.resolve();
       if (!(element instanceof PsiVariable)) {
         return false;
       }
       final PsiVariable variable = (PsiVariable) element;
       if (!IteratorUtils.containsCallToScannerNext(context, variable, true)) {
         notUpdated.add(qualifierExpression);
         return true;
       }
     } else {
       if (!IteratorUtils.containsCallToScannerNext(context, null, true)) {
         notUpdated.add(methodCallExpression);
         return true;
       }
     }
   }
   return false;
 }