@Nullable
static HighlightInfo checkVariableMustBeFinal(
PsiVariable variable,
PsiJavaCodeReferenceElement context,
@NotNull LanguageLevel languageLevel) {
if (variable.hasModifierProperty(PsiModifier.FINAL)) return null;
final PsiClass innerClass = getInnerClassVariableReferencedFrom(variable, context);
if (innerClass != null) {
if (variable instanceof PsiParameter) {
final PsiElement parent = variable.getParent();
if (parent instanceof PsiParameterList
&& parent.getParent() instanceof PsiLambdaExpression
&& notAccessedForWriting(
variable, new LocalSearchScope(((PsiParameter) variable).getDeclarationScope()))) {
return null;
}
}
if (languageLevel.isAtLeast(LanguageLevel.JDK_1_8)
&& isEffectivelyFinal(variable, innerClass, context)) {
return null;
}
final String description =
JavaErrorMessages.message("variable.must.be.final", context.getText());
final HighlightInfo highlightInfo =
HighlightInfo.newHighlightInfo(HighlightInfoType.ERROR)
.range(context)
.descriptionAndTooltip(description)
.create();
QuickFixAction.registerQuickFixAction(
highlightInfo,
QUICK_FIX_FACTORY.createVariableAccessFromInnerClassFix(variable, innerClass));
return highlightInfo;
}
final PsiLambdaExpression lambdaExpression =
PsiTreeUtil.getParentOfType(context, PsiLambdaExpression.class);
if (lambdaExpression != null && !PsiTreeUtil.isAncestor(lambdaExpression, variable, true)) {
final PsiElement parent = variable.getParent();
if (parent instanceof PsiParameterList && parent.getParent() == lambdaExpression) {
return null;
}
if (!isEffectivelyFinal(variable, lambdaExpression, context)) {
return HighlightInfo.newHighlightInfo(HighlightInfoType.ERROR)
.range(context)
.descriptionAndTooltip("Variable used in lambda expression should be effectively final")
.create();
}
}
return null;
}
@Nullable
public static PsiElement getInnerClassVariableReferencedFrom(
@NotNull PsiVariable variable, @NotNull PsiElement context) {
final PsiElement[] scope;
if (variable instanceof PsiResourceVariable) {
scope = ((PsiResourceVariable) variable).getDeclarationScope();
} else if (variable instanceof PsiLocalVariable) {
final PsiElement parent = variable.getParent();
scope =
new PsiElement[] {
parent != null ? parent.getParent() : null
}; // code block or for statement
} else if (variable instanceof PsiParameter) {
scope = new PsiElement[] {((PsiParameter) variable).getDeclarationScope()};
} else {
scope = new PsiElement[] {variable.getParent()};
}
if (scope.length < 1
|| scope[0] == null
|| scope[0].getContainingFile() != context.getContainingFile()) return null;
PsiElement parent = context.getParent();
PsiElement prevParent = context;
outer:
while (parent != null) {
for (PsiElement scopeElement : scope) {
if (parent.equals(scopeElement)) break outer;
}
if (parent instanceof PsiClass
&& !(prevParent instanceof PsiExpressionList && parent instanceof PsiAnonymousClass)) {
return parent;
}
if (parent instanceof PsiLambdaExpression) {
return parent;
}
prevParent = parent;
parent = parent.getParent();
}
return null;
}
public static boolean isReassigned(
PsiVariable variable,
Map<PsiElement, Collection<ControlFlowUtil.VariableInfo>> finalVarProblems) {
if (variable instanceof PsiLocalVariable) {
final PsiElement parent = variable.getParent();
if (parent == null) return false;
final PsiElement declarationScope = parent.getParent();
Collection<ControlFlowUtil.VariableInfo> codeBlockProblems =
getFinalVariableProblemsInBlock(finalVarProblems, declarationScope);
return codeBlockProblems.contains(new ControlFlowUtil.VariableInfo(variable, null));
} else if (variable instanceof PsiParameter) {
final PsiParameter parameter = (PsiParameter) variable;
return isAssigned(parameter);
} else {
return false;
}
}
@Nullable
static HighlightInfo checkVariableMustBeFinal(
@NotNull PsiVariable variable,
@NotNull PsiJavaCodeReferenceElement context,
@NotNull LanguageLevel languageLevel) {
if (variable.hasModifierProperty(PsiModifier.FINAL)) return null;
final PsiElement innerClass = getInnerClassVariableReferencedFrom(variable, context);
if (innerClass instanceof PsiClass) {
if (variable instanceof PsiParameter) {
final PsiElement parent = variable.getParent();
if (parent instanceof PsiParameterList
&& parent.getParent() instanceof PsiLambdaExpression
&& notAccessedForWriting(
variable, new LocalSearchScope(((PsiParameter) variable).getDeclarationScope()))) {
return null;
}
}
final boolean isToBeEffectivelyFinal = languageLevel.isAtLeast(LanguageLevel.JDK_1_8);
if (isToBeEffectivelyFinal && isEffectivelyFinal(variable, innerClass, context)) {
return null;
}
final String description =
JavaErrorMessages.message(
isToBeEffectivelyFinal
? "variable.must.be.final.or.effectively.final"
: "variable.must.be.final",
context.getText());
final HighlightInfo highlightInfo =
HighlightInfo.newHighlightInfo(HighlightInfoType.ERROR)
.range(context)
.descriptionAndTooltip(description)
.create();
QuickFixAction.registerQuickFixAction(
highlightInfo,
QUICK_FIX_FACTORY.createVariableAccessFromInnerClassFix(variable, innerClass));
return highlightInfo;
}
return checkWriteToFinalInsideLambda(variable, context);
}
private static HighlightInfo checkWriteToFinalInsideLambda(
@NotNull PsiVariable variable, @NotNull PsiJavaCodeReferenceElement context) {
final PsiLambdaExpression lambdaExpression =
PsiTreeUtil.getParentOfType(context, PsiLambdaExpression.class);
if (lambdaExpression != null && !PsiTreeUtil.isAncestor(lambdaExpression, variable, true)) {
final PsiElement parent = variable.getParent();
if (parent instanceof PsiParameterList && parent.getParent() == lambdaExpression) {
return null;
}
if (!isEffectivelyFinal(variable, lambdaExpression, context)) {
String text = JavaErrorMessages.message("lambda.variable.must.be.final");
HighlightInfo highlightInfo =
HighlightInfo.newHighlightInfo(HighlightInfoType.ERROR)
.range(context)
.descriptionAndTooltip(text)
.create();
QuickFixAction.registerQuickFixAction(
highlightInfo,
QUICK_FIX_FACTORY.createVariableAccessFromInnerClassFix(variable, lambdaExpression));
return highlightInfo;
}
}
return null;
}
/**
* @param sideEffects if null, delete usages, otherwise collect side effects
* @return true if there are at least one unrecoverable side effect found, false if no side
* effects, null if read usage found (may happen if interval between fix creation in invoke()
* call was long enough)
* @throws com.intellij.util.IncorrectOperationException
*/
static Boolean processUsage(
PsiElement element, PsiVariable variable, List<PsiElement> sideEffects, int deleteMode)
throws IncorrectOperationException {
if (!element.isValid()) return null;
PsiElementFactory factory =
JavaPsiFacade.getInstance(variable.getProject()).getElementFactory();
while (element != null) {
if (element instanceof PsiAssignmentExpression) {
PsiAssignmentExpression expression = (PsiAssignmentExpression) element;
PsiExpression lExpression = expression.getLExpression();
// there should not be read access to the variable, otherwise it is not unused
if (!(lExpression instanceof PsiReferenceExpression)
|| variable != ((PsiReferenceExpression) lExpression).resolve()) {
return null;
}
PsiExpression rExpression = expression.getRExpression();
rExpression = PsiUtil.deparenthesizeExpression(rExpression);
if (rExpression == null) return true;
// replace assignment with expression and resimplify
boolean sideEffectFound = checkSideEffects(rExpression, variable, sideEffects);
if (!(element.getParent() instanceof PsiExpressionStatement)
|| PsiUtil.isStatement(rExpression)) {
if (deleteMode == MAKE_STATEMENT
|| deleteMode == DELETE_ALL
&& !(element.getParent() instanceof PsiExpressionStatement)) {
element = replaceElementWithExpression(rExpression, factory, element);
while (element.getParent() instanceof PsiParenthesizedExpression) {
element = element.getParent().replace(element);
}
List<PsiElement> references = new ArrayList<PsiElement>();
collectReferences(element, variable, references);
deleteReferences(variable, references, deleteMode);
} else if (deleteMode == DELETE_ALL) {
deleteWholeStatement(element, factory);
}
return true;
} else {
if (deleteMode != CANCEL) {
deleteWholeStatement(element, factory);
}
return !sideEffectFound;
}
} else if (element instanceof PsiExpressionStatement && deleteMode != CANCEL) {
final PsiElement parent = element.getParent();
if (parent instanceof PsiIfStatement
|| parent instanceof PsiLoopStatement
&& ((PsiLoopStatement) parent).getBody() == element) {
element.replace(
JavaPsiFacade.getElementFactory(element.getProject())
.createStatementFromText(";", element));
} else {
element.delete();
}
break;
} else if (element instanceof PsiVariable && element == variable) {
PsiExpression expression = variable.getInitializer();
if (expression != null) {
expression = PsiUtil.deparenthesizeExpression(expression);
}
boolean sideEffectsFound = checkSideEffects(expression, variable, sideEffects);
if (expression != null
&& PsiUtil.isStatement(expression)
&& variable instanceof PsiLocalVariable
&& !(variable.getParent() instanceof PsiDeclarationStatement
&& ((PsiDeclarationStatement) variable.getParent()).getDeclaredElements().length
> 1)) {
if (deleteMode == MAKE_STATEMENT) {
element = element.replace(createStatementIfNeeded(expression, factory, element));
List<PsiElement> references = new ArrayList<PsiElement>();
collectReferences(element, variable, references);
deleteReferences(variable, references, deleteMode);
} else if (deleteMode == DELETE_ALL) {
element.delete();
}
return true;
} else {
if (deleteMode != CANCEL) {
if (element instanceof PsiField) {
((PsiField) element).normalizeDeclaration();
}
element.delete();
}
return !sideEffectsFound;
}
}
element = element.getParent();
}
return true;
}
@Nullable
public static HighlightInfo checkFinalVariableMightAlreadyHaveBeenAssignedTo(
@NotNull PsiVariable variable,
@NotNull PsiReferenceExpression expression,
@NotNull Map<PsiElement, Collection<ControlFlowUtil.VariableInfo>> finalVarProblems) {
if (!PsiUtil.isAccessedForWriting(expression)) return null;
final PsiElement scope =
variable instanceof PsiField
? variable.getParent()
: variable.getParent() == null ? null : variable.getParent().getParent();
PsiElement codeBlock = PsiUtil.getTopLevelEnclosingCodeBlock(expression, scope);
if (codeBlock == null) return null;
Collection<ControlFlowUtil.VariableInfo> codeBlockProblems =
getFinalVariableProblemsInBlock(finalVarProblems, codeBlock);
boolean alreadyAssigned = false;
for (ControlFlowUtil.VariableInfo variableInfo : codeBlockProblems) {
if (variableInfo.expression == expression) {
alreadyAssigned = true;
break;
}
}
if (!alreadyAssigned) {
if (!(variable instanceof PsiField)) return null;
final PsiField field = (PsiField) variable;
final PsiClass aClass = field.getContainingClass();
if (aClass == null) return null;
// field can get assigned in other field initializers
final PsiField[] fields = aClass.getFields();
boolean isFieldStatic = field.hasModifierProperty(PsiModifier.STATIC);
for (PsiField psiField : fields) {
PsiExpression initializer = psiField.getInitializer();
if (psiField != field
&& psiField.hasModifierProperty(PsiModifier.STATIC) == isFieldStatic
&& initializer != null
&& initializer != codeBlock
&& !variableDefinitelyNotAssignedIn(field, initializer)) {
alreadyAssigned = true;
break;
}
}
if (!alreadyAssigned) {
// field can get assigned in class initializers
final PsiMember enclosingConstructorOrInitializer =
PsiUtil.findEnclosingConstructorOrInitializer(expression);
if (enclosingConstructorOrInitializer == null
|| !aClass
.getManager()
.areElementsEquivalent(
enclosingConstructorOrInitializer.getContainingClass(), aClass)) {
return null;
}
final PsiClassInitializer[] initializers = aClass.getInitializers();
for (PsiClassInitializer initializer : initializers) {
if (initializer.hasModifierProperty(PsiModifier.STATIC)
== field.hasModifierProperty(PsiModifier.STATIC)) {
final PsiCodeBlock body = initializer.getBody();
if (body == codeBlock) return null;
try {
final ControlFlow controlFlow = getControlFlow(body);
if (!ControlFlowUtil.isVariableDefinitelyNotAssigned(field, controlFlow)) {
alreadyAssigned = true;
break;
}
} catch (AnalysisCanceledException e) {
// incomplete code
return null;
}
}
}
}
if (!alreadyAssigned && !field.hasModifierProperty(PsiModifier.STATIC)) {
// then check if instance field already assigned in other constructor
final PsiMethod ctr =
codeBlock.getParent() instanceof PsiMethod ? (PsiMethod) codeBlock.getParent() : null;
// assignment to final field in several constructors threatens us only if these are linked
// (there is this() call in the beginning)
final List<PsiMethod> redirectedConstructors =
ctr != null && ctr.isConstructor()
? JavaHighlightUtil.getChainedConstructors(ctr)
: null;
for (int j = 0; redirectedConstructors != null && j < redirectedConstructors.size(); j++) {
PsiMethod redirectedConstructor = redirectedConstructors.get(j);
PsiCodeBlock body = redirectedConstructor.getBody();
if (body != null && variableDefinitelyAssignedIn(variable, body)) {
alreadyAssigned = true;
break;
}
}
}
}
if (alreadyAssigned) {
String description =
JavaErrorMessages.message("variable.already.assigned", variable.getName());
final HighlightInfo highlightInfo =
HighlightInfo.newHighlightInfo(HighlightInfoType.ERROR)
.range(expression)
.descriptionAndTooltip(description)
.create();
QuickFixAction.registerQuickFixAction(
highlightInfo,
QUICK_FIX_FACTORY.createModifierListFix(variable, PsiModifier.FINAL, false, false));
QuickFixAction.registerQuickFixAction(
highlightInfo, QUICK_FIX_FACTORY.createDeferFinalAssignmentFix(variable, expression));
return highlightInfo;
}
return null;
}
@Nullable
public static HighlightInfo checkVariableInitializedBeforeUsage(
@NotNull PsiReferenceExpression expression,
@NotNull PsiVariable variable,
@NotNull Map<PsiElement, Collection<PsiReferenceExpression>> uninitializedVarProblems,
@NotNull PsiFile containingFile) {
if (variable instanceof ImplicitVariable) return null;
if (!PsiUtil.isAccessedForReading(expression)) return null;
int startOffset = expression.getTextRange().getStartOffset();
final PsiElement topBlock;
if (variable.hasInitializer()) {
topBlock = PsiUtil.getVariableCodeBlock(variable, variable);
if (topBlock == null) return null;
} else {
PsiElement scope =
variable instanceof PsiField
? ((PsiField) variable).getContainingClass()
: variable.getParent() != null ? variable.getParent().getParent() : null;
if (scope instanceof PsiCodeBlock && scope.getParent() instanceof PsiSwitchStatement) {
scope = PsiTreeUtil.getParentOfType(scope, PsiCodeBlock.class);
}
topBlock =
FileTypeUtils.isInServerPageFile(scope) && scope instanceof PsiFile
? scope
: PsiUtil.getTopLevelEnclosingCodeBlock(expression, scope);
if (variable instanceof PsiField) {
// non final field already initialized with default value
if (!variable.hasModifierProperty(PsiModifier.FINAL)) return null;
// final field may be initialized in ctor or class initializer only
// if we're inside non-ctr method, skip it
if (PsiUtil.findEnclosingConstructorOrInitializer(expression) == null
&& HighlightUtil.findEnclosingFieldInitializer(expression) == null) {
return null;
}
if (topBlock == null) return null;
final PsiElement parent = topBlock.getParent();
// access to final fields from inner classes always allowed
if (inInnerClass(expression, ((PsiField) variable).getContainingClass(), containingFile))
return null;
final PsiCodeBlock block;
final PsiClass aClass;
if (parent instanceof PsiMethod) {
PsiMethod constructor = (PsiMethod) parent;
if (!containingFile
.getManager()
.areElementsEquivalent(
constructor.getContainingClass(), ((PsiField) variable).getContainingClass()))
return null;
// static variables already initialized in class initializers
if (variable.hasModifierProperty(PsiModifier.STATIC)) return null;
// as a last chance, field may be initialized in this() call
final List<PsiMethod> redirectedConstructors =
JavaHighlightUtil.getChainedConstructors(constructor);
for (int j = 0;
redirectedConstructors != null && j < redirectedConstructors.size();
j++) {
PsiMethod redirectedConstructor = redirectedConstructors.get(j);
// variable must be initialized before its usage
// ???
// if (startOffset < redirectedConstructor.getTextRange().getStartOffset()) continue;
PsiCodeBlock body = redirectedConstructor.getBody();
if (body != null && variableDefinitelyAssignedIn(variable, body)) {
return null;
}
}
block = constructor.getBody();
aClass = constructor.getContainingClass();
} else if (parent instanceof PsiClassInitializer) {
final PsiClassInitializer classInitializer = (PsiClassInitializer) parent;
if (!containingFile
.getManager()
.areElementsEquivalent(
classInitializer.getContainingClass(),
((PsiField) variable).getContainingClass())) return null;
block = classInitializer.getBody();
aClass = classInitializer.getContainingClass();
} else {
// field reference outside code block
// check variable initialized before its usage
final PsiField field = (PsiField) variable;
aClass = field.getContainingClass();
if (aClass == null
|| isFieldInitializedInOtherFieldInitializer(
aClass, field, field.hasModifierProperty(PsiModifier.STATIC))) {
return null;
}
final PsiField anotherField =
PsiTreeUtil.getTopmostParentOfType(expression, PsiField.class);
int offset = startOffset;
if (anotherField != null
&& anotherField.getContainingClass() == aClass
&& !field.hasModifierProperty(PsiModifier.STATIC)) {
offset = 0;
}
block = null;
// initializers will be checked later
final PsiMethod[] constructors = aClass.getConstructors();
for (PsiMethod constructor : constructors) {
// variable must be initialized before its usage
if (offset < constructor.getTextRange().getStartOffset()) continue;
PsiCodeBlock body = constructor.getBody();
if (body != null && variableDefinitelyAssignedIn(variable, body)) {
return null;
}
// as a last chance, field may be initialized in this() call
final List<PsiMethod> redirectedConstructors =
JavaHighlightUtil.getChainedConstructors(constructor);
for (int j = 0;
redirectedConstructors != null && j < redirectedConstructors.size();
j++) {
PsiMethod redirectedConstructor = redirectedConstructors.get(j);
// variable must be initialized before its usage
if (offset < redirectedConstructor.getTextRange().getStartOffset()) continue;
PsiCodeBlock redirectedBody = redirectedConstructor.getBody();
if (redirectedBody != null
&& variableDefinitelyAssignedIn(variable, redirectedBody)) {
return null;
}
}
}
}
if (aClass != null) {
// field may be initialized in class initializer
final PsiClassInitializer[] initializers = aClass.getInitializers();
for (PsiClassInitializer initializer : initializers) {
PsiCodeBlock body = initializer.getBody();
if (body == block) break;
// variable referenced in initializer must be initialized in initializer preceding
// assignment
// variable referenced in field initializer or in class initializer
boolean shouldCheckInitializerOrder =
block == null || block.getParent() instanceof PsiClassInitializer;
if (shouldCheckInitializerOrder
&& startOffset < initializer.getTextRange().getStartOffset()) continue;
if (initializer.hasModifierProperty(PsiModifier.STATIC)
== variable.hasModifierProperty(PsiModifier.STATIC)) {
if (variableDefinitelyAssignedIn(variable, body)) return null;
}
}
}
}
}
if (topBlock == null) return null;
Collection<PsiReferenceExpression> codeBlockProblems = uninitializedVarProblems.get(topBlock);
if (codeBlockProblems == null) {
try {
final ControlFlow controlFlow = getControlFlow(topBlock);
codeBlockProblems = ControlFlowUtil.getReadBeforeWriteLocals(controlFlow);
} catch (AnalysisCanceledException | IndexNotReadyException e) {
codeBlockProblems = Collections.emptyList();
}
uninitializedVarProblems.put(topBlock, codeBlockProblems);
}
if (codeBlockProblems.contains(expression)) {
final String name = expression.getElement().getText();
String description = JavaErrorMessages.message("variable.not.initialized", name);
HighlightInfo highlightInfo =
HighlightInfo.newHighlightInfo(HighlightInfoType.ERROR)
.range(expression)
.descriptionAndTooltip(description)
.create();
QuickFixAction.registerQuickFixAction(
highlightInfo, QUICK_FIX_FACTORY.createAddVariableInitializerFix(variable));
if (variable instanceof PsiField) {
QuickFixAction.registerQuickFixAction(
highlightInfo,
QUICK_FIX_FACTORY.createModifierListFix(variable, PsiModifier.FINAL, false, false));
}
return highlightInfo;
}
return null;
}
private void addTypesByVariable(
HashSet<PsiType> typesSet,
PsiVariable var,
PsiFile scopeFile,
HashSet<PsiVariable> checkedVariables,
int flags,
TextRange rangeToIgnore) {
if (!checkedVariables.add(var)) return;
// System.out.println("analyzing usages of " + var + " in file " + scopeFile);
SearchScope searchScope = new LocalSearchScope(scopeFile);
if (BitUtil.isSet(flags, CHECK_USAGE) || BitUtil.isSet(flags, CHECK_DOWN)) {
for (PsiReference varRef : ReferencesSearch.search(var, searchScope, false)) {
PsiElement ref = varRef.getElement();
if (BitUtil.isSet(flags, CHECK_USAGE)) {
PsiType type = guessElementTypeFromReference(myMethodPatternMap, ref, rangeToIgnore);
if (type != null && !(type instanceof PsiPrimitiveType)) {
typesSet.add(type);
}
}
if (BitUtil.isSet(flags, CHECK_DOWN)) {
if (ref.getParent() instanceof PsiExpressionList
&& ref.getParent().getParent() instanceof PsiMethodCallExpression) { // TODO : new
PsiExpressionList list = (PsiExpressionList) ref.getParent();
PsiExpression[] args = list.getExpressions();
int argIndex = -1;
for (int j = 0; j < args.length; j++) {
PsiExpression arg = args[j];
if (arg.equals(ref)) {
argIndex = j;
break;
}
}
PsiMethodCallExpression methodCall = (PsiMethodCallExpression) list.getParent();
PsiMethod method = (PsiMethod) methodCall.getMethodExpression().resolve();
if (method != null) {
PsiParameter[] parameters = method.getParameterList().getParameters();
if (argIndex < parameters.length) {
addTypesByVariable(
typesSet,
parameters[argIndex],
method.getContainingFile(),
checkedVariables,
flags | CHECK_USAGE,
rangeToIgnore);
}
}
}
}
}
}
if (BitUtil.isSet(flags, CHECK_UP)) {
if (var instanceof PsiParameter
&& var.getParent() instanceof PsiParameterList
&& var.getParent().getParent() instanceof PsiMethod) {
PsiParameterList list = (PsiParameterList) var.getParent();
PsiParameter[] parameters = list.getParameters();
int argIndex = -1;
for (int i = 0; i < parameters.length; i++) {
PsiParameter parameter = parameters[i];
if (parameter.equals(var)) {
argIndex = i;
break;
}
}
PsiMethod method = (PsiMethod) var.getParent().getParent();
// System.out.println("analyzing usages of " + method + " in file " + scopeFile);
for (PsiReference methodRef : ReferencesSearch.search(method, searchScope, false)) {
PsiElement ref = methodRef.getElement();
if (ref.getParent() instanceof PsiMethodCallExpression) {
PsiMethodCallExpression methodCall = (PsiMethodCallExpression) ref.getParent();
PsiExpression[] args = methodCall.getArgumentList().getExpressions();
if (args.length <= argIndex) continue;
PsiExpression arg = args[argIndex];
if (arg instanceof PsiReferenceExpression) {
PsiElement refElement = ((PsiReferenceExpression) arg).resolve();
if (refElement instanceof PsiVariable) {
addTypesByVariable(
typesSet,
(PsiVariable) refElement,
scopeFile,
checkedVariables,
flags | CHECK_USAGE,
rangeToIgnore);
}
}
// TODO : constructor
}
}
}
}
}