@Nullable
private Collection<DfaMemoryState> createInitialStates(
@NotNull PsiElement psiBlock, @NotNull InstructionVisitor visitor) {
PsiElement container =
PsiTreeUtil.getParentOfType(psiBlock, PsiClass.class, PsiLambdaExpression.class);
if (container != null
&& (!(container instanceof PsiClass)
|| PsiUtil.isLocalOrAnonymousClass((PsiClass) container))) {
final PsiElement parent = container.getParent();
final PsiCodeBlock block = DfaPsiUtil.getTopmostBlockInSameClass(parent);
if (block != null) {
final RunnerResult result = analyzeMethod(block, visitor);
if (result == RunnerResult.OK) {
final Collection<DfaMemoryState> closureStates =
myNestedClosures.get(DfaPsiUtil.getTopmostBlockInSameClass(psiBlock));
if (!closureStates.isEmpty()) {
return closureStates;
}
}
return null;
}
}
return Collections.singletonList(createMemoryState());
}
@Nullable
private static Map<PsiExpression, PsiType> buildDataflowTypeMap(PsiExpression forPlace) {
PsiElement scope = DfaPsiUtil.getTopmostBlockInSameClass(forPlace);
if (scope == null) {
PsiFile file = forPlace.getContainingFile();
if (!(file instanceof PsiCodeFragment)) {
return Collections.emptyMap();
}
scope = file;
}
DataFlowRunner runner =
new DataFlowRunner() {
@NotNull
@Override
protected DfaMemoryState createMemoryState() {
return new ExpressionTypeMemoryState(getFactory());
}
};
final ExpressionTypeInstructionVisitor visitor = new ExpressionTypeInstructionVisitor(forPlace);
if (runner.analyzeMethod(scope, visitor) == RunnerResult.OK) {
return visitor.getResult();
}
return null;
}
@Override
protected Nullness create(MethodCallInstruction key) {
final PsiCallExpression callExpression = key.getCallExpression();
if (callExpression instanceof PsiNewExpression) {
return Nullness.NOT_NULL;
}
return callExpression != null
? DfaPsiUtil.getElementNullability(
key.getResultType(), callExpression.resolveMethod())
: null;
}
@Nullable
private Collection<DfaMemoryState> createInitialStates(
@NotNull PsiElement psiBlock, InstructionVisitor visitor) {
PsiClass containingClass = PsiTreeUtil.getParentOfType(psiBlock, PsiClass.class);
if (containingClass != null && PsiUtil.isLocalOrAnonymousClass(containingClass)) {
final PsiElement parent = containingClass.getParent();
final PsiCodeBlock block = DfaPsiUtil.getTopmostBlockInSameClass(parent);
if ((parent instanceof PsiNewExpression || parent instanceof PsiDeclarationStatement)
&& block != null) {
final RunnerResult result = analyzeMethod(block, visitor);
if (result == RunnerResult.OK) {
final Collection<DfaMemoryState> closureStates =
myNestedClosures.get(DfaPsiUtil.getTopmostBlockInSameClass(psiBlock));
if (!closureStates.isEmpty()) {
return closureStates;
}
}
return null;
}
}
return Arrays.asList(createMemoryState());
}
@NotNull
public static Nullness checkNullness(
@Nullable final PsiVariable variable, @Nullable final PsiElement context) {
if (variable == null || context == null) return Nullness.UNKNOWN;
final PsiElement codeBlock = DfaPsiUtil.getEnclosingCodeBlock(variable, context);
if (codeBlock == null) {
return Nullness.UNKNOWN;
}
final ValuableInstructionVisitor visitor = new ValuableInstructionVisitor(context);
RunnerResult result = new ValuableDataFlowRunner().analyzeMethod(codeBlock, visitor);
if (result != RunnerResult.OK) {
return Nullness.UNKNOWN;
}
if (visitor.myNulls.contains(variable) && !visitor.myNotNulls.contains(variable))
return Nullness.NULLABLE;
if (visitor.myNotNulls.contains(variable) && !visitor.myNulls.contains(variable))
return Nullness.NOT_NULL;
return Nullness.UNKNOWN;
}
@Nullable("null means DFA analysis has failed (too complex to analyze)")
public static Collection<PsiExpression> getCachedVariableValues(
@Nullable final PsiVariable variable, @Nullable final PsiElement context) {
if (variable == null || context == null) return Collections.emptyList();
CachedValue<MultiValuesMap<PsiVariable, PsiExpression>> cachedValue =
context.getUserData(DFA_VARIABLE_INFO_KEY);
if (cachedValue == null) {
final PsiElement codeBlock = DfaPsiUtil.getEnclosingCodeBlock(variable, context);
cachedValue =
CachedValuesManager.getManager(context.getProject())
.createCachedValue(
new CachedValueProvider<MultiValuesMap<PsiVariable, PsiExpression>>() {
@Override
public Result<MultiValuesMap<PsiVariable, PsiExpression>> compute() {
final MultiValuesMap<PsiVariable, PsiExpression> result;
if (codeBlock == null) {
result = null;
} else {
final ValuableInstructionVisitor visitor =
new ValuableInstructionVisitor(context);
RunnerResult runnerResult =
new ValuableDataFlowRunner().analyzeMethod(codeBlock, visitor);
if (runnerResult == RunnerResult.OK) {
result = visitor.myValues;
} else {
result = TOO_COMPLEX;
}
}
return new Result<MultiValuesMap<PsiVariable, PsiExpression>>(
result, variable);
}
},
false);
context.putUserData(DFA_VARIABLE_INFO_KEY, cachedValue);
}
final MultiValuesMap<PsiVariable, PsiExpression> value = cachedValue.getValue();
if (value == TOO_COMPLEX) return null;
final Collection<PsiExpression> expressions = value == null ? null : value.get(variable);
return expressions == null ? Collections.<PsiExpression>emptyList() : expressions;
}
@NotNull
public static Collection<? extends PsiElement> getPossibleInitializationElements(
final PsiElement qualifierExpression) {
if (qualifierExpression instanceof PsiMethodCallExpression) {
return Collections.singletonList(qualifierExpression);
}
if (qualifierExpression instanceof PsiReferenceExpression) {
final PsiElement targetElement = ((PsiReferenceExpression) qualifierExpression).resolve();
if (!(targetElement instanceof PsiVariable)) {
return Collections.emptyList();
}
final Collection<? extends PsiElement> variableValues =
getCachedVariableValues((PsiVariable) targetElement, qualifierExpression);
if (variableValues == null || variableValues.isEmpty()) {
return DfaPsiUtil.getVariableAssignmentsInFile(
(PsiVariable) targetElement, false, qualifierExpression);
}
return variableValues;
}
if (qualifierExpression instanceof PsiLiteralExpression) {
return Collections.singletonList(qualifierExpression);
}
return Collections.emptyList();
}
