private static void checkCodeBlock(
final PsiCodeBlock body, final Set<PsiField> candidates, Set<PsiField> usedFields) {
try {
final ControlFlow controlFlow =
ControlFlowFactory.getInstance(body.getProject())
.getControlFlow(body, AllVariablesControlFlowPolicy.getInstance());
final List<PsiVariable> usedVars =
ControlFlowUtil.getUsedVariables(controlFlow, 0, controlFlow.getSize());
for (PsiVariable usedVariable : usedVars) {
if (usedVariable instanceof PsiField) {
final PsiField usedField = (PsiField) usedVariable;
if (!usedFields.add(usedField)) {
candidates.remove(usedField); // used in more than one code block
}
}
}
final List<PsiReferenceExpression> readBeforeWrites =
ControlFlowUtil.getReadBeforeWrite(controlFlow);
for (final PsiReferenceExpression readBeforeWrite : readBeforeWrites) {
final PsiElement resolved = readBeforeWrite.resolve();
if (resolved instanceof PsiField) {
final PsiField field = (PsiField) resolved;
PsiElement parent = body.getParent();
if (!(parent instanceof PsiMethod)
|| !((PsiMethod) parent).isConstructor()
|| field.getInitializer() == null
|| field.hasModifierProperty(PsiModifier.STATIC)) {
candidates.remove(field);
}
}
}
} catch (AnalysisCanceledException e) {
candidates.clear();
}
}
private PsiElement addDeclarationWithFieldInitializerAndRetargetReferences(
final PsiElementFactory elementFactory,
final String localName,
final PsiCodeBlock anchorBlock,
final PsiElement anchor,
final Set<PsiReference> refs)
throws IncorrectOperationException {
final PsiDeclarationStatement decl =
elementFactory.createVariableDeclarationStatement(
localName, myField.getType(), myField.getInitializer());
final PsiElement newDeclaration = anchorBlock.addBefore(decl, anchor);
retargetReferences(elementFactory, localName, refs);
return newDeclaration;
}
@Override
public void onReferencesBuild(RefElement refElement) {
if (refElement instanceof RefClass) {
final PsiClass psiClass = (PsiClass) refElement.getElement();
if (psiClass != null) {
if (refElement.isEntry()) {
((RefClassImpl) refElement).setFlag(false, CAN_BE_FINAL_MASK);
}
PsiMethod[] psiMethods = psiClass.getMethods();
PsiField[] psiFields = psiClass.getFields();
HashSet<PsiVariable> allFields = new HashSet<PsiVariable>();
ContainerUtil.addAll(allFields, psiFields);
ArrayList<PsiVariable> instanceInitializerInitializedFields = new ArrayList<PsiVariable>();
boolean hasInitializers = false;
for (PsiClassInitializer initializer : psiClass.getInitializers()) {
PsiCodeBlock body = initializer.getBody();
hasInitializers = true;
ControlFlow flow;
try {
flow =
ControlFlowFactory.getInstance(body.getProject())
.getControlFlow(
body, LocalsOrMyInstanceFieldsControlFlowPolicy.getInstance(), false);
} catch (AnalysisCanceledException e) {
flow = ControlFlow.EMPTY;
}
Collection<PsiVariable> writtenVariables = new ArrayList<PsiVariable>();
ControlFlowUtil.getWrittenVariables(flow, 0, flow.getSize(), false, writtenVariables);
for (PsiVariable psiVariable : writtenVariables) {
if (allFields.contains(psiVariable)) {
if (instanceInitializerInitializedFields.contains(psiVariable)) {
allFields.remove(psiVariable);
instanceInitializerInitializedFields.remove(psiVariable);
} else {
instanceInitializerInitializedFields.add(psiVariable);
}
}
}
for (PsiVariable psiVariable : writtenVariables) {
if (!instanceInitializerInitializedFields.contains(psiVariable)) {
allFields.remove(psiVariable);
}
}
}
for (PsiMethod psiMethod : psiMethods) {
if (psiMethod.isConstructor()) {
PsiCodeBlock body = psiMethod.getBody();
if (body != null) {
hasInitializers = true;
ControlFlow flow;
try {
flow =
ControlFlowFactory.getInstance(body.getProject())
.getControlFlow(
body, LocalsOrMyInstanceFieldsControlFlowPolicy.getInstance(), false);
} catch (AnalysisCanceledException e) {
flow = ControlFlow.EMPTY;
}
Collection<PsiVariable> writtenVariables =
ControlFlowUtil.getWrittenVariables(flow, 0, flow.getSize(), false);
for (PsiVariable psiVariable : writtenVariables) {
if (instanceInitializerInitializedFields.contains(psiVariable)) {
allFields.remove(psiVariable);
instanceInitializerInitializedFields.remove(psiVariable);
}
}
List<PsiMethod> redirectedConstructors =
HighlightControlFlowUtil.getChainedConstructors(psiMethod);
if (redirectedConstructors == null || redirectedConstructors.isEmpty()) {
List<PsiVariable> ssaVariables = ControlFlowUtil.getSSAVariables(flow);
ArrayList<PsiVariable> good = new ArrayList<PsiVariable>(ssaVariables);
good.addAll(instanceInitializerInitializedFields);
allFields.retainAll(good);
} else {
allFields.removeAll(writtenVariables);
}
}
}
}
for (PsiField psiField : psiFields) {
if ((!hasInitializers || !allFields.contains(psiField))
&& psiField.getInitializer() == null) {
final RefFieldImpl refField = (RefFieldImpl) myManager.getReference(psiField);
if (refField != null) {
refField.setFlag(false, CAN_BE_FINAL_MASK);
}
}
}
}
} else if (refElement instanceof RefMethod) {
final RefMethod refMethod = (RefMethod) refElement;
if (refMethod.isEntry()) {
((RefMethodImpl) refMethod).setFlag(false, CAN_BE_FINAL_MASK);
}
}
}
@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;
}