public static PsiType[] getErasedParameterTypes(MethodSignature signature) {
PsiType[] parameterTypes = signature.getParameterTypes();
if (parameterTypes.length == 0) return PsiType.EMPTY_ARRAY;
PsiSubstitutor substitutor = signature.getSubstitutor();
PsiType[] erasedTypes = new PsiType[parameterTypes.length];
for (int i = 0; i < parameterTypes.length; i++) {
erasedTypes[i] =
TypeConversionUtil.erasure(substitutor.substitute(parameterTypes[i]), substitutor);
}
return erasedTypes;
}
@Override
public int computeHashCode(final MethodSignature signature) {
int result = signature.isConstructor() ? 0 : signature.getName().hashCode();
PsiType[] parameterTypes = signature.getParameterTypes();
result += 37 * parameterTypes.length;
PsiType firstParamType = parameterTypes.length == 0 ? null : parameterTypes[0];
if (firstParamType != null) {
firstParamType = TypeConversionUtil.erasure(firstParamType, signature.getSubstitutor());
assert firstParamType != null : parameterTypes[0];
result = 31 * result + firstParamType.hashCode();
}
return result;
}
public static boolean isSubsignature(
@NotNull MethodSignature superSignature, @NotNull MethodSignature subSignature) {
if (subSignature == superSignature) return true;
if (!areSignaturesEqualLightweight(superSignature, subSignature)) return false;
PsiSubstitutor unifyingSubstitutor =
getSuperMethodSignatureSubstitutor(subSignature, superSignature);
if (checkSignaturesEqualInner(superSignature, subSignature, unifyingSubstitutor)) return true;
if (subSignature.getTypeParameters().length > 0) return false;
final PsiType[] subParameterTypes = subSignature.getParameterTypes();
final PsiType[] superParameterTypes = superSignature.getParameterTypes();
for (int i = 0; i < subParameterTypes.length; i++) {
PsiType type1 = subParameterTypes[i];
PsiType type2 =
TypeConversionUtil.erasure(superParameterTypes[i], superSignature.getSubstitutor());
if (!Comparing.equal(type1, type2)) return false;
}
return true;
}
@Nullable
private static PsiSubstitutor getSuperMethodSignatureSubstitutorImpl(
@NotNull MethodSignature methodSignature, @NotNull MethodSignature superSignature) {
// normalize generic method declarations: correlate type parameters
// todo: correlate type params by name?
PsiTypeParameter[] methodTypeParameters = methodSignature.getTypeParameters();
PsiTypeParameter[] superTypeParameters = superSignature.getTypeParameters();
// both methods are parameterized and number of parameters mismatch
if (methodTypeParameters.length != superTypeParameters.length) return null;
PsiSubstitutor result = superSignature.getSubstitutor();
for (int i = 0; i < methodTypeParameters.length; i++) {
PsiTypeParameter methodTypeParameter = methodTypeParameters[i];
PsiElementFactory factory =
JavaPsiFacade.getInstance(methodTypeParameter.getProject()).getElementFactory();
result = result.put(superTypeParameters[i], factory.createType(methodTypeParameter));
}
return result;
}
/**
* @param methodSignature method signature
* @param superMethodSignature super method signature
* @return null if signatures do not match
*/
@Nullable
public static PsiSubstitutor getSuperMethodSignatureSubstitutor(
@NotNull MethodSignature methodSignature, @NotNull MethodSignature superMethodSignature) {
PsiSubstitutor result =
getSuperMethodSignatureSubstitutorImpl(methodSignature, superMethodSignature);
if (result == null) return null;
PsiTypeParameter[] methodTypeParameters = methodSignature.getTypeParameters();
PsiTypeParameter[] superTypeParameters = superMethodSignature.getTypeParameters();
PsiSubstitutor methodSubstitutor = methodSignature.getSubstitutor();
// check bounds
for (int i = 0; i < methodTypeParameters.length; i++) {
PsiTypeParameter methodTypeParameter = methodTypeParameters[i];
PsiTypeParameter superTypeParameter = superTypeParameters[i];
final Set<PsiType> methodSupers = new HashSet<PsiType>();
for (PsiClassType methodSuper : methodTypeParameter.getSuperTypes()) {
methodSupers.add(methodSubstitutor.substitute(methodSuper));
}
final Set<PsiType> superSupers = new HashSet<PsiType>();
for (PsiClassType superSuper : superTypeParameter.getSuperTypes()) {
superSupers.add(
methodSubstitutor.substitute(
PsiUtil.captureToplevelWildcards(
result.substitute(superSuper), methodTypeParameter)));
}
methodSupers.remove(
PsiType.getJavaLangObject(
methodTypeParameter.getManager(), methodTypeParameter.getResolveScope()));
superSupers.remove(
PsiType.getJavaLangObject(
superTypeParameter.getManager(), superTypeParameter.getResolveScope()));
if (!methodSupers.equals(superSupers)) return null;
}
return result;
}
public static boolean isAcceptable(
PsiLambdaExpression lambdaExpression, final PsiType leftType, boolean checkReturnType) {
if (leftType instanceof PsiIntersectionType) {
for (PsiType conjunctType : ((PsiIntersectionType) leftType).getConjuncts()) {
if (isAcceptable(lambdaExpression, conjunctType, checkReturnType)) return true;
}
return false;
}
final PsiClassType.ClassResolveResult resolveResult =
PsiUtil.resolveGenericsClassInType(GenericsUtil.eliminateWildcards(leftType));
final PsiClass psiClass = resolveResult.getElement();
if (psiClass instanceof PsiAnonymousClass) {
return isAcceptable(
lambdaExpression, ((PsiAnonymousClass) psiClass).getBaseClassType(), checkReturnType);
}
final MethodSignature methodSignature = getFunction(psiClass);
if (methodSignature == null) return false;
final PsiParameter[] lambdaParameters = lambdaExpression.getParameterList().getParameters();
final PsiType[] parameterTypes = methodSignature.getParameterTypes();
if (lambdaParameters.length != parameterTypes.length) return false;
for (int lambdaParamIdx = 0, length = lambdaParameters.length;
lambdaParamIdx < length;
lambdaParamIdx++) {
PsiParameter parameter = lambdaParameters[lambdaParamIdx];
final PsiTypeElement typeElement = parameter.getTypeElement();
if (typeElement != null) {
final PsiType lambdaFormalType = typeElement.getType();
final PsiType methodParameterType = parameterTypes[lambdaParamIdx];
if (lambdaFormalType instanceof PsiPrimitiveType) {
if (methodParameterType instanceof PsiPrimitiveType)
return methodParameterType.equals(lambdaFormalType);
return false;
}
if (!TypeConversionUtil.erasure(lambdaFormalType)
.isAssignableFrom(
TypeConversionUtil.erasure(
GenericsUtil.eliminateWildcards(
resolveResult
.getSubstitutor()
.substitute(
methodSignature
.getSubstitutor()
.substitute(methodParameterType)))))) {
return false;
}
}
}
if (checkReturnType) {
final String uniqueVarName =
JavaCodeStyleManager.getInstance(lambdaExpression.getProject())
.suggestUniqueVariableName("l", lambdaExpression, true);
String canonicalText = leftType.getCanonicalText();
if (leftType instanceof PsiEllipsisType) {
canonicalText = ((PsiEllipsisType) leftType).toArrayType().getCanonicalText();
}
final PsiStatement assignmentFromText =
JavaPsiFacade.getElementFactory(lambdaExpression.getProject())
.createStatementFromText(
canonicalText + " " + uniqueVarName + " = " + lambdaExpression.getText(),
lambdaExpression);
final PsiLocalVariable localVariable =
(PsiLocalVariable)
((PsiDeclarationStatement) assignmentFromText).getDeclaredElements()[0];
LOG.assertTrue(psiClass != null);
PsiType methodReturnType = getReturnType(psiClass, methodSignature);
if (methodReturnType != null) {
methodReturnType =
resolveResult
.getSubstitutor()
.substitute(methodSignature.getSubstitutor().substitute(methodReturnType));
return LambdaHighlightingUtil.checkReturnTypeCompatible(
(PsiLambdaExpression) localVariable.getInitializer(), methodReturnType)
== null;
}
}
return true;
}