| /******************************************************************************* |
| * Copyright (c) 2013, 2015 GK Software AG and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| * Contributors: |
| * Stephan Herrmann - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.jdt.internal.compiler.ast; |
| |
| import org.eclipse.jdt.internal.compiler.flow.FlowContext; |
| import org.eclipse.jdt.internal.compiler.flow.FlowInfo; |
| import org.eclipse.jdt.internal.compiler.impl.CompilerOptions; |
| import org.eclipse.jdt.internal.compiler.lookup.AnnotationBinding; |
| import org.eclipse.jdt.internal.compiler.lookup.ArrayBinding; |
| import org.eclipse.jdt.internal.compiler.lookup.Binding; |
| import org.eclipse.jdt.internal.compiler.lookup.BlockScope; |
| import org.eclipse.jdt.internal.compiler.lookup.CaptureBinding; |
| import org.eclipse.jdt.internal.compiler.lookup.InvocationSite; |
| import org.eclipse.jdt.internal.compiler.lookup.LookupEnvironment; |
| import org.eclipse.jdt.internal.compiler.lookup.MethodBinding; |
| import org.eclipse.jdt.internal.compiler.lookup.ParameterizedTypeBinding; |
| import org.eclipse.jdt.internal.compiler.lookup.ProblemMethodBinding; |
| import org.eclipse.jdt.internal.compiler.lookup.ProblemReasons; |
| import org.eclipse.jdt.internal.compiler.lookup.RawTypeBinding; |
| import org.eclipse.jdt.internal.compiler.lookup.ReferenceBinding; |
| import org.eclipse.jdt.internal.compiler.lookup.Scope; |
| import org.eclipse.jdt.internal.compiler.lookup.TagBits; |
| import org.eclipse.jdt.internal.compiler.lookup.TypeBinding; |
| import org.eclipse.jdt.internal.compiler.lookup.TypeBindingVisitor; |
| import org.eclipse.jdt.internal.compiler.lookup.TypeIds; |
| import org.eclipse.jdt.internal.compiler.lookup.TypeVariableBinding; |
| import org.eclipse.jdt.internal.compiler.lookup.VariableBinding; |
| import org.eclipse.jdt.internal.compiler.lookup.WildcardBinding; |
| |
| /** |
| * Performs matching of null type annotations. |
| * Instances are used to encode result from this analysis. |
| * @since 3.10 |
| */ |
| public class NullAnnotationMatching { |
| |
| public static final NullAnnotationMatching NULL_ANNOTATIONS_OK = new NullAnnotationMatching(0, FlowInfo.UNKNOWN, null); |
| public static final NullAnnotationMatching NULL_ANNOTATIONS_OK_NONNULL = new NullAnnotationMatching(0, FlowInfo.NON_NULL, null); |
| public static final NullAnnotationMatching NULL_ANNOTATIONS_UNCHECKED = new NullAnnotationMatching(1, FlowInfo.UNKNOWN, null); |
| public static final NullAnnotationMatching NULL_ANNOTATIONS_MISMATCH = new NullAnnotationMatching(2, FlowInfo.UNKNOWN, null); |
| |
| public enum CheckMode { |
| /** in this mode we check normal assignment compatibility. */ |
| COMPATIBLE, |
| /** in this mode we do not tolerate incompatibly missing annotations on type parameters (for overriding analysis) */ |
| OVERRIDE, |
| /** in this mode we check compatibility of a type argument against the corresponding type parameter. */ |
| BOUND_CHECK |
| } |
| |
| /** 0 = OK, 1 = unchecked, 2 = definite mismatch */ |
| public final int severity; |
| |
| /** If non-null this field holds the supertype of the provided type which was used for direct matching. */ |
| public final TypeBinding superTypeHint; |
| public final int nullStatus; |
| |
| public NullAnnotationMatching(int severity, int nullStatus, TypeBinding superTypeHint) { |
| this.severity = severity; |
| this.superTypeHint = superTypeHint; |
| this.nullStatus = nullStatus; |
| } |
| |
| public boolean isAnyMismatch() { return this.severity != 0; } |
| public boolean isUnchecked() { return this.severity == 1; } |
| public boolean isDefiniteMismatch() { return this.severity == 2; } |
| |
| public boolean isPotentiallyNullMismatch() { |
| return !isDefiniteMismatch() && this.nullStatus != -1 && (this.nullStatus & FlowInfo.POTENTIALLY_NULL) != 0; |
| } |
| |
| public String superTypeHintName(CompilerOptions options, boolean shortNames) { |
| return String.valueOf(this.superTypeHint.nullAnnotatedReadableName(options, shortNames)); |
| } |
| |
| /** Check null-ness of 'var' against a possible null annotation */ |
| public static int checkAssignment(BlockScope currentScope, FlowContext flowContext, |
| VariableBinding var, FlowInfo flowInfo, int nullStatus, Expression expression, TypeBinding providedType) |
| { |
| if (providedType == null) return FlowInfo.UNKNOWN; // assume we already reported an error |
| long lhsTagBits = 0L; |
| boolean hasReported = false; |
| if (!currentScope.environment().usesNullTypeAnnotations()) { |
| lhsTagBits = var.tagBits & TagBits.AnnotationNullMASK; |
| } else { |
| if (expression instanceof ConditionalExpression && expression.isPolyExpression()) { |
| // drill into both branches: |
| ConditionalExpression ce = ((ConditionalExpression) expression); |
| int status1 = NullAnnotationMatching.checkAssignment(currentScope, flowContext, var, flowInfo, ce.ifTrueNullStatus, ce.valueIfTrue, ce.valueIfTrue.resolvedType); |
| int status2 = NullAnnotationMatching.checkAssignment(currentScope, flowContext, var, flowInfo, ce.ifFalseNullStatus, ce.valueIfFalse, ce.valueIfFalse.resolvedType); |
| if (status1 == status2) |
| return status1; |
| return nullStatus; // if both branches disagree use the precomputed & merged nullStatus |
| } |
| lhsTagBits = var.type.tagBits & TagBits.AnnotationNullMASK; |
| NullAnnotationMatching annotationStatus = analyse(var.type, providedType, nullStatus); |
| if (annotationStatus.isAnyMismatch()) { |
| flowContext.recordNullityMismatch(currentScope, expression, providedType, var.type, flowInfo, nullStatus, annotationStatus); |
| hasReported = true; |
| } else if (annotationStatus.nullStatus != FlowInfo.UNKNOWN) { |
| return annotationStatus.nullStatus; |
| } |
| } |
| if (lhsTagBits == TagBits.AnnotationNonNull && nullStatus != FlowInfo.NON_NULL) { |
| if (!hasReported) |
| flowContext.recordNullityMismatch(currentScope, expression, providedType, var.type, flowInfo, nullStatus, null); |
| return FlowInfo.NON_NULL; |
| } else if (lhsTagBits == TagBits.AnnotationNullable && nullStatus == FlowInfo.UNKNOWN) { // provided a legacy type? |
| return FlowInfo.POTENTIALLY_NULL; // -> use more specific info from the annotation |
| } |
| return nullStatus; |
| } |
| |
| /** |
| * Find any mismatches between the two given types, which are caused by null type annotations. |
| * @param requiredType |
| * @param providedType |
| * @param nullStatus we are only interested in NULL or NON_NULL, -1 indicates that we are in a recursion, where flow info is ignored |
| * @return a status object representing the severity of mismatching plus optionally a supertype hint |
| */ |
| public static NullAnnotationMatching analyse(TypeBinding requiredType, TypeBinding providedType, int nullStatus) { |
| return analyse(requiredType, providedType, null, nullStatus, CheckMode.COMPATIBLE); |
| } |
| /** |
| * Find any mismatches between the two given types, which are caused by null type annotations. |
| * @param requiredType |
| * @param providedType |
| * @param providedSubstitute in inheritance situations this maps the providedType into the realm of the subclass, needed for TVB identity checks. |
| * Pass null if not interested in these added checks. |
| * @param nullStatus we are only interested in NULL or NON_NULL, -1 indicates that we are in a recursion, where flow info is ignored |
| * @param mode controls the kind of check performed (see {@link CheckMode}). |
| * @return a status object representing the severity of mismatching plus optionally a supertype hint |
| */ |
| public static NullAnnotationMatching analyse(TypeBinding requiredType, TypeBinding providedType, TypeBinding providedSubstitute, int nullStatus, CheckMode mode) { |
| if (!requiredType.enterRecursiveFunction()) |
| return NullAnnotationMatching.NULL_ANNOTATIONS_OK; |
| try { |
| int severity = 0; |
| TypeBinding superTypeHint = null; |
| NullAnnotationMatching okStatus = NullAnnotationMatching.NULL_ANNOTATIONS_OK; |
| if (areSameTypes(requiredType, providedType, providedSubstitute)) { |
| if ((requiredType.tagBits & TagBits.AnnotationNonNull) != 0) |
| return NullAnnotationMatching.NULL_ANNOTATIONS_OK_NONNULL; |
| return okStatus; |
| } |
| if (mode == CheckMode.BOUND_CHECK && requiredType instanceof TypeVariableBinding) { |
| // during bound check against a type variable check the provided type against all upper bounds: |
| TypeBinding superClass = requiredType.superclass(); |
| if (superClass != null && superClass.hasNullTypeAnnotations()) { |
| NullAnnotationMatching status = analyse(superClass, providedType, null, nullStatus, mode); |
| severity = Math.max(severity, status.severity); |
| if (severity == 2) |
| return new NullAnnotationMatching(severity, nullStatus, superTypeHint); |
| } |
| TypeBinding[] superInterfaces = requiredType.superInterfaces(); |
| if (superInterfaces != null) { |
| for (int i = 0; i < superInterfaces.length; i++) { |
| if (superInterfaces[i].hasNullTypeAnnotations()) { |
| NullAnnotationMatching status = analyse(superInterfaces[i], providedType, null, nullStatus, mode); |
| severity = Math.max(severity, status.severity); |
| if (severity == 2) |
| return new NullAnnotationMatching(severity, nullStatus, superTypeHint); |
| } |
| } |
| } |
| } |
| if (requiredType instanceof ArrayBinding) { |
| long[] requiredDimsTagBits = ((ArrayBinding)requiredType).nullTagBitsPerDimension; |
| if (requiredDimsTagBits != null) { |
| int dims = requiredType.dimensions(); |
| if (requiredType.dimensions() == providedType.dimensions()) { |
| long[] providedDimsTagBits = ((ArrayBinding)providedType).nullTagBitsPerDimension; |
| if (providedDimsTagBits == null) |
| providedDimsTagBits = new long[dims+1]; // set to unspec'd at all dimensions |
| int currentNullStatus = nullStatus; |
| for (int i=0; i<=dims; i++) { |
| long requiredBits = validNullTagBits(requiredDimsTagBits[i]); |
| long providedBits = validNullTagBits(providedDimsTagBits[i]); |
| if (i > 0) |
| currentNullStatus = -1; // don't use beyond the outermost dimension |
| severity = Math.max(severity, computeNullProblemSeverity(requiredBits, providedBits, currentNullStatus, mode == CheckMode.OVERRIDE && nullStatus == -1)); |
| if (severity == 2) |
| return NullAnnotationMatching.NULL_ANNOTATIONS_MISMATCH; |
| if (severity == 0) |
| nullStatus = -1; |
| } |
| } else if (providedType.id == TypeIds.T_null) { |
| if (dims > 0 && requiredDimsTagBits[0] == TagBits.AnnotationNonNull) |
| return NullAnnotationMatching.NULL_ANNOTATIONS_MISMATCH; |
| } |
| } |
| } else if (requiredType.hasNullTypeAnnotations() || providedType.hasNullTypeAnnotations() || requiredType.isTypeVariable()) { |
| long requiredBits = requiredNullTagBits(requiredType, mode); |
| if (requiredBits != TagBits.AnnotationNullable // nullable lhs accepts everything, ... |
| || nullStatus == -1) // only at detail/recursion even nullable must be matched exactly |
| { |
| long providedBits = providedNullTagBits(providedType); |
| int s = computeNullProblemSeverity(requiredBits, providedBits, nullStatus, mode == CheckMode.OVERRIDE && nullStatus == -1); |
| severity = Math.max(severity, s); |
| if (severity == 0 && (providedBits & TagBits.AnnotationNonNull) != 0) |
| okStatus = NullAnnotationMatching.NULL_ANNOTATIONS_OK_NONNULL; |
| } |
| if (severity < 2) { |
| TypeBinding providedSuper = providedType.findSuperTypeOriginatingFrom(requiredType); |
| TypeBinding providedSubstituteSuper = providedSubstitute != null ? providedSubstitute.findSuperTypeOriginatingFrom(requiredType) : null; |
| if (providedSuper != providedType) //$IDENTITY-COMPARISON$ |
| superTypeHint = providedSuper; |
| if (requiredType.isParameterizedType() && providedSuper instanceof ParameterizedTypeBinding) { // TODO(stephan): handle providedType.isRaw() |
| TypeBinding[] requiredArguments = ((ParameterizedTypeBinding) requiredType).arguments; |
| TypeBinding[] providedArguments = ((ParameterizedTypeBinding) providedSuper).arguments; |
| TypeBinding[] providedSubstitutes = (providedSubstituteSuper instanceof ParameterizedTypeBinding) ? ((ParameterizedTypeBinding)providedSubstituteSuper).arguments : null; |
| if (requiredArguments != null && providedArguments != null && requiredArguments.length == providedArguments.length) { |
| for (int i = 0; i < requiredArguments.length; i++) { |
| TypeBinding providedArgSubstitute = providedSubstitutes != null ? providedSubstitutes[i] : null; |
| NullAnnotationMatching status = analyse(requiredArguments[i], providedArguments[i], providedArgSubstitute, -1, mode); |
| severity = Math.max(severity, status.severity); |
| if (severity == 2) |
| return new NullAnnotationMatching(severity, nullStatus, superTypeHint); |
| } |
| } |
| } |
| TypeBinding requiredEnclosing = requiredType.enclosingType(); |
| TypeBinding providedEnclosing = providedType.enclosingType(); |
| if (requiredEnclosing != null && providedEnclosing != null) { |
| TypeBinding providedEnclSubstitute = providedSubstitute != null ? providedSubstitute.enclosingType() : null; |
| NullAnnotationMatching status = analyse(requiredEnclosing, providedEnclosing, providedEnclSubstitute, -1, mode); |
| severity = Math.max(severity, status.severity); |
| } |
| } |
| } |
| if (severity == 0) |
| return okStatus; |
| return new NullAnnotationMatching(severity, nullStatus, superTypeHint); |
| } finally { |
| requiredType.exitRecursiveFunction(); |
| } |
| } |
| |
| /** Are both types identical wrt the unannotated type and any null type annotations? Only unstructured types and captures are considered. */ |
| protected static boolean areSameTypes(TypeBinding requiredType, TypeBinding providedType, TypeBinding providedSubstitute) { |
| if (requiredType == providedType) //$IDENTITY-COMPARISON$ // short cut for really-really-same types |
| return true; |
| if (requiredType.isParameterizedType() || requiredType.isArrayType()) |
| return false; // not analysing details here |
| if (TypeBinding.notEquals(requiredType, providedType)) { |
| if (requiredType instanceof CaptureBinding) { |
| // when providing exactly the lower bound of the required type we're definitely fine: |
| TypeBinding lowerBound = ((CaptureBinding)requiredType).lowerBound; |
| if (lowerBound != null && areSameTypes(lowerBound, providedType, providedSubstitute)) |
| return true; |
| } else if (requiredType.kind() == Binding.TYPE_PARAMETER && requiredType == providedSubstitute) { //$IDENTITY-COMPARISON$ |
| return true; |
| } else if (providedType instanceof CaptureBinding) { |
| // when requiring exactly the upper bound of the provided type we're fine, too: |
| TypeBinding upperBound = ((CaptureBinding)providedType).upperBound(); |
| if (upperBound != null && areSameTypes(requiredType, upperBound, providedSubstitute)) |
| return true; |
| } |
| return false; |
| } |
| return (requiredType.tagBits & TagBits.AnnotationNullMASK) == (providedType.tagBits & TagBits.AnnotationNullMASK); |
| } |
| |
| // interpreting 'type' as a required type, compute the required null bits |
| // we inspect the main type plus bounds of type variables and wildcards |
| static long requiredNullTagBits(TypeBinding type, CheckMode mode) { |
| |
| long tagBits = type.tagBits & TagBits.AnnotationNullMASK; |
| if (tagBits != 0) |
| return validNullTagBits(tagBits); |
| |
| if (type.isWildcard()) { |
| WildcardBinding wildcard = (WildcardBinding)type; |
| if (wildcard.boundKind == Wildcard.UNBOUND) |
| return 0; |
| tagBits = wildcard.bound.tagBits & TagBits.AnnotationNullMASK; |
| if (tagBits == 0) |
| return 0; |
| switch (wildcard.boundKind) { |
| case Wildcard.EXTENDS : |
| if (tagBits == TagBits.AnnotationNonNull) |
| return TagBits.AnnotationNonNull; |
| return TagBits.AnnotationNullMASK; // wildcard accepts @Nullable or better |
| case Wildcard.SUPER : |
| if (tagBits == TagBits.AnnotationNullable) |
| return TagBits.AnnotationNullable; |
| return TagBits.AnnotationNullMASK; // wildcard accepts @NonNull or worse |
| } |
| return 0; |
| } |
| |
| if (type.isTypeVariable()) { |
| // assume we must require @NonNull, unless lower @Nullable bound |
| // (annotation directly on the TV has already been checked above) |
| if (type.isCapture()) { |
| TypeBinding lowerBound = ((CaptureBinding) type).lowerBound; |
| if (lowerBound != null) { |
| tagBits = lowerBound.tagBits & TagBits.AnnotationNullMASK; |
| if (tagBits == TagBits.AnnotationNullable) |
| return TagBits.AnnotationNullable; // type cannot require @NonNull |
| } |
| } |
| if (mode != CheckMode.BOUND_CHECK) // no pessimistic checks during boundcheck (we *have* the instantiation) |
| return TagBits.AnnotationNonNull; // instantiation could require @NonNull |
| } |
| |
| return 0; |
| } |
| |
| // interpreting 'type' as a provided type, compute the provide null bits |
| // we inspect the main type plus bounds of type variables and wildcards |
| static long providedNullTagBits(TypeBinding type) { |
| |
| long tagBits = type.tagBits & TagBits.AnnotationNullMASK; |
| if (tagBits != 0) |
| return validNullTagBits(tagBits); |
| |
| if (type.isWildcard()) { // wildcard can be 'provided' during inheritance checks |
| WildcardBinding wildcard = (WildcardBinding)type; |
| if (wildcard.boundKind == Wildcard.UNBOUND) |
| return 0; |
| tagBits = wildcard.bound.tagBits & TagBits.AnnotationNullMASK; |
| if (tagBits == 0) |
| return 0; |
| switch (wildcard.boundKind) { |
| case Wildcard.EXTENDS : |
| if (tagBits == TagBits.AnnotationNonNull) |
| return TagBits.AnnotationNonNull; |
| return TagBits.AnnotationNullMASK; // @Nullable or better |
| case Wildcard.SUPER : |
| if (tagBits == TagBits.AnnotationNullable) |
| return TagBits.AnnotationNullable; |
| return TagBits.AnnotationNullMASK; // @NonNull or worse |
| } |
| return 0; |
| } |
| |
| if (type.isTypeVariable()) { // incl. captures |
| TypeVariableBinding typeVariable = (TypeVariableBinding)type; |
| boolean haveNullBits = false; |
| if (typeVariable.isCapture()) { |
| TypeBinding lowerBound = ((CaptureBinding) typeVariable).lowerBound; |
| if (lowerBound != null) { |
| tagBits = lowerBound.tagBits & TagBits.AnnotationNullMASK; |
| if (tagBits == TagBits.AnnotationNullable) |
| return TagBits.AnnotationNullable; // cannot be @NonNull |
| haveNullBits |= (tagBits != 0); |
| } |
| } |
| if (typeVariable.firstBound != null) { |
| long boundBits = typeVariable.firstBound.tagBits & TagBits.AnnotationNullMASK; |
| if (boundBits == TagBits.AnnotationNonNull) |
| return TagBits.AnnotationNonNull; // cannot be @Nullable |
| haveNullBits |= (boundBits != 0); |
| } |
| if (haveNullBits) |
| return TagBits.AnnotationNullMASK; // could be either, can only match to a wildcard accepting both |
| } |
| |
| return 0; |
| } |
| |
| public static long validNullTagBits(long bits) { |
| bits &= TagBits.AnnotationNullMASK; |
| return bits == TagBits.AnnotationNullMASK ? 0 : bits; |
| } |
| |
| /** Provided that both types are {@link TypeBinding#equalsEquals}, return the one that is more likely to show null at runtime. */ |
| public static TypeBinding moreDangerousType(TypeBinding one, TypeBinding two) { |
| if (one == null) return null; |
| long oneNullBits = validNullTagBits(one.tagBits); |
| long twoNullBits = validNullTagBits(two.tagBits); |
| if (oneNullBits != twoNullBits) { |
| if (oneNullBits == TagBits.AnnotationNullable) |
| return one; // nullable is dangerous |
| if (twoNullBits == TagBits.AnnotationNullable) |
| return two; // nullable is dangerous |
| // below this point we have unknown vs. nonnull, which is which? |
| if (oneNullBits == 0) |
| return one; // unknown is more dangerous than nonnull |
| return two; // unknown is more dangerous than nonnull |
| } else if (one != two) { //$IDENTITY-COMPARISON$ |
| if (analyse(one, two, -1).isAnyMismatch()) |
| return two; // two doesn't snugly fit into one, so it must be more dangerous |
| } |
| return one; |
| } |
| |
| /** |
| * Evaluate problem severity from the given details: |
| * @param requiredBits null tagBits of the required type |
| * @param providedBits null tagBits of the provided type |
| * @param nullStatus -1 means: don't use, other values see constants in FlowInfo |
| * @param overrideDetailChecking true enables strictest mode during override analysis when checking type details (type argument, array content) |
| * @return see {@link #severity} for interpretation of values |
| */ |
| private static int computeNullProblemSeverity(long requiredBits, long providedBits, int nullStatus, boolean overrideDetailChecking) { |
| // nullStatus: |
| // overrideDetailChecking: |
| if ((requiredBits != 0 || overrideDetailChecking) && requiredBits != providedBits) { |
| if (requiredBits == TagBits.AnnotationNonNull && nullStatus == FlowInfo.NON_NULL) { |
| return 0; // OK by flow analysis |
| } |
| if (requiredBits == TagBits.AnnotationNullMASK) |
| return 0; // OK since LHS accepts either |
| if (nullStatus != -1 && !overrideDetailChecking && requiredBits == TagBits.AnnotationNullable) |
| return 0; // when using flow info, everything is compatible to nullable |
| if (providedBits != 0) { |
| return 2; // mismatching annotations |
| } else { |
| return 1; // need unchecked conversion regarding type detail |
| } |
| } |
| return 0; // OK by tagBits |
| } |
| |
| static class SearchContradictions extends TypeBindingVisitor { |
| ReferenceBinding typeWithContradiction; |
| @Override |
| public boolean visit(ReferenceBinding referenceBinding) { |
| if ((referenceBinding.tagBits & TagBits.AnnotationNullMASK) == TagBits.AnnotationNullMASK) { |
| this.typeWithContradiction = referenceBinding; |
| return false; |
| } |
| return true; |
| } |
| @Override |
| public boolean visit(TypeVariableBinding typeVariable) { |
| if (!visit((ReferenceBinding)typeVariable)) |
| return false; |
| long allNullBits = typeVariable.tagBits & TagBits.AnnotationNullMASK; |
| if (typeVariable.firstBound != null) |
| allNullBits = typeVariable.firstBound.tagBits & TagBits.AnnotationNullMASK; |
| for (TypeBinding otherBound : typeVariable.otherUpperBounds()) |
| allNullBits |= otherBound.tagBits & TagBits.AnnotationNullMASK; |
| if (allNullBits == TagBits.AnnotationNullMASK) { |
| this.typeWithContradiction = typeVariable; |
| return false; |
| } |
| return true; |
| } |
| @Override |
| public boolean visit(RawTypeBinding rawType) { |
| return visit((ReferenceBinding)rawType); |
| } |
| @Override |
| public boolean visit(WildcardBinding wildcardBinding) { |
| long allNullBits = wildcardBinding.tagBits & TagBits.AnnotationNullMASK; |
| switch (wildcardBinding.boundKind) { |
| case Wildcard.EXTENDS: |
| allNullBits |= wildcardBinding.bound.tagBits & TagBits.AnnotationNonNull; |
| break; |
| case Wildcard.SUPER: |
| allNullBits |= wildcardBinding.bound.tagBits & TagBits.AnnotationNullable; |
| break; |
| } |
| if (allNullBits == TagBits.AnnotationNullMASK) { |
| this.typeWithContradiction = wildcardBinding; |
| return false; |
| } |
| return true; |
| } |
| @Override |
| public boolean visit(ParameterizedTypeBinding parameterizedTypeBinding) { |
| if (!visit((ReferenceBinding) parameterizedTypeBinding)) |
| return false; |
| return super.visit(parameterizedTypeBinding); |
| } |
| } |
| |
| /** |
| * After a method has substituted type parameters, check if this resulted in any contradictory null annotations. |
| * Problems are either reported directly (if scope != null) or by returning a ProblemMethodBinding. |
| */ |
| public static MethodBinding checkForContradictions(MethodBinding method, Object location, Scope scope) { |
| |
| int start = 0, end = 0; |
| if (location instanceof InvocationSite) { |
| start = ((InvocationSite) location).sourceStart(); |
| end = ((InvocationSite) location).sourceEnd(); |
| } else if (location instanceof ASTNode) { |
| start = ((ASTNode) location).sourceStart; |
| end = ((ASTNode) location).sourceEnd; |
| } |
| SearchContradictions searchContradiction = new SearchContradictions(); |
| TypeBindingVisitor.visit(searchContradiction, method.returnType); |
| if (searchContradiction.typeWithContradiction != null) { |
| if (scope == null) |
| return new ProblemMethodBinding(method, method.selector, method.parameters, ProblemReasons.ContradictoryNullAnnotations); |
| scope.problemReporter().contradictoryNullAnnotationsInferred(method, start, end, location instanceof FunctionalExpression); |
| // note: if needed, we might want to update the method by removing the contradictory annotations?? |
| return method; |
| } |
| |
| Expression[] arguments = null; |
| if (location instanceof Invocation) |
| arguments = ((Invocation)location).arguments(); |
| for (int i = 0; i < method.parameters.length; i++) { |
| TypeBindingVisitor.visit(searchContradiction, method.parameters[i]); |
| if (searchContradiction.typeWithContradiction != null) { |
| if (scope == null) |
| return new ProblemMethodBinding(method, method.selector, method.parameters, ProblemReasons.ContradictoryNullAnnotations); |
| if (arguments != null && i < arguments.length) |
| scope.problemReporter().contradictoryNullAnnotationsInferred(method, arguments[i]); |
| else |
| scope.problemReporter().contradictoryNullAnnotationsInferred(method, start, end, location instanceof FunctionalExpression); |
| return method; |
| } |
| } |
| return method; |
| } |
| |
| public static boolean hasContradictions(TypeBinding type) { |
| SearchContradictions searchContradiction = new SearchContradictions(); |
| TypeBindingVisitor.visit(searchContradiction, type); |
| return searchContradiction.typeWithContradiction != null; |
| } |
| |
| public static TypeBinding strongerType(TypeBinding type1, TypeBinding type2, LookupEnvironment environment) { |
| if ((type1.tagBits & TagBits.AnnotationNonNull) != 0) |
| return mergeTypeAnnotations(type1, type2, true, environment); |
| return mergeTypeAnnotations(type2, type1, true, environment); // don't bother to distinguish unannotated vs. @Nullable, since both can accept null |
| } |
| |
| public static TypeBinding[] weakerTypes(TypeBinding[] parameters1, TypeBinding[] parameters2, LookupEnvironment environment) { |
| TypeBinding[] newParameters = new TypeBinding[parameters1.length]; |
| for (int i = 0; i < newParameters.length; i++) { |
| long tagBits1 = parameters1[i].tagBits; |
| long tagBits2 = parameters2[i].tagBits; |
| if ((tagBits1 & TagBits.AnnotationNullable) != 0) |
| newParameters[i] = mergeTypeAnnotations(parameters1[i], parameters2[i], true, environment); // @Nullable must be preserved |
| else if ((tagBits2 & TagBits.AnnotationNullable) != 0) |
| newParameters[i] = mergeTypeAnnotations(parameters2[i], parameters1[i], true, environment); // @Nullable must be preserved |
| else if ((tagBits1 & TagBits.AnnotationNonNull) == 0) |
| newParameters[i] = mergeTypeAnnotations(parameters1[i], parameters2[i], true, environment); // unannotated must be preserved |
| else |
| newParameters[i] = mergeTypeAnnotations(parameters2[i], parameters1[i], true, environment); // either unannotated, or both are @NonNull |
| } |
| return newParameters; |
| } |
| private static TypeBinding mergeTypeAnnotations(TypeBinding type, TypeBinding otherType, boolean top, LookupEnvironment environment) { |
| TypeBinding mainType = type; |
| if (!top) { |
| // for all but the top level type superimpose other's type annotation onto type |
| AnnotationBinding[] otherAnnotations = otherType.getTypeAnnotations(); |
| if (otherAnnotations != Binding.NO_ANNOTATIONS) |
| mainType = environment.createAnnotatedType(type, otherAnnotations); |
| } |
| if (mainType.isParameterizedType() && otherType.isParameterizedType()) { |
| ParameterizedTypeBinding ptb = (ParameterizedTypeBinding) type, otherPTB = (ParameterizedTypeBinding) otherType; |
| TypeBinding[] typeArguments = ptb.arguments; |
| TypeBinding[] otherTypeArguments = otherPTB.arguments; |
| TypeBinding[] newTypeArguments = new TypeBinding[typeArguments.length]; |
| for (int i = 0; i < typeArguments.length; i++) { |
| newTypeArguments[i] = mergeTypeAnnotations(typeArguments[i], otherTypeArguments[i], false, environment); |
| } |
| return environment.createParameterizedType(ptb.genericType(), newTypeArguments, ptb.enclosingType()); |
| } |
| return mainType; |
| } |
| } |
