Beispiel #1
0
 public boolean checkUnsafeCast(
     Scope scope,
     TypeBinding castType,
     TypeBinding expressionType,
     TypeBinding match,
     boolean isNarrowing) {
   if (match == castType) {
     if (!isNarrowing
         && match
             == this.resolvedType
                 .leafComponentType()) { // do not tag as unnecessary when recursing through upper
       // bounds
       tagAsUnnecessaryCast(scope, castType);
     }
     return true;
   }
   if (match != null) {
     if (isNarrowing
         ? match.isProvablyDistinct(expressionType)
         : castType.isProvablyDistinct(match)) {
       return false;
     }
   }
   switch (castType.kind()) {
     case Binding.PARAMETERIZED_TYPE:
       if (castType.isBoundParameterizedType()) {
         if (match == null) { // unrelated types
           this.bits |= ASTNode.UnsafeCast;
           return true;
         }
         switch (match.kind()) {
           case Binding.PARAMETERIZED_TYPE:
             if (isNarrowing) {
               // [JLS 5.5] T <: S
               if (expressionType.isRawType() || !expressionType.isEquivalentTo(match)) {
                 this.bits |= ASTNode.UnsafeCast;
                 return true;
               }
               // [JLS 5.5] S has no subtype X != T, such that |X| == |T|
               // if I2<T,U> extends I1<T>, then cast from I1<T> to I2<T,U> is unchecked
               ParameterizedTypeBinding paramCastType = (ParameterizedTypeBinding) castType;
               ParameterizedTypeBinding paramMatch = (ParameterizedTypeBinding) match;
               // easy case if less parameters on match
               TypeBinding[] castArguments = paramCastType.arguments;
               int length = castArguments.length;
               if (paramMatch.arguments == null || length > paramMatch.arguments.length) {
                 this.bits |= ASTNode.UnsafeCast;
               } else if ((paramCastType.tagBits
                       & (TagBits.HasDirectWildcard | TagBits.HasTypeVariable))
                   != 0) {
                 // verify alternate cast type, substituting different type arguments
                 nextAlternateArgument:
                 for (int i = 0; i < length; i++) {
                   switch (castArguments[i].kind()) {
                     case Binding.WILDCARD_TYPE:
                     case Binding.TYPE_PARAMETER:
                       break; // check substituting with other
                     default:
                       continue nextAlternateArgument; // no alternative possible
                   }
                   TypeBinding[] alternateArguments;
                   // need to clone for each iteration to avoid env paramtype cache interference
                   System.arraycopy(
                       paramCastType.arguments,
                       0,
                       alternateArguments = new TypeBinding[length],
                       0,
                       length);
                   alternateArguments[i] = scope.getJavaLangObject();
                   LookupEnvironment environment = scope.environment();
                   ParameterizedTypeBinding alternateCastType =
                       environment.createParameterizedType(
                           (ReferenceBinding) castType.erasure(),
                           alternateArguments,
                           castType.enclosingType());
                   if (alternateCastType.findSuperTypeOriginatingFrom(expressionType) == match) {
                     this.bits |= ASTNode.UnsafeCast;
                     break;
                   }
                 }
               }
               return true;
             } else {
               // [JLS 5.5] T >: S
               if (!match.isEquivalentTo(castType)) {
                 this.bits |= ASTNode.UnsafeCast;
                 return true;
               }
             }
             break;
           case Binding.RAW_TYPE:
             this.bits |=
                 ASTNode.UnsafeCast; // upcast since castType is known to be bound paramType
             return true;
           default:
             if (isNarrowing) {
               // match is not parameterized or raw, then any other subtype of match will erase  to
               // |T|
               this.bits |= ASTNode.UnsafeCast;
               return true;
             }
             break;
         }
       }
       break;
     case Binding.ARRAY_TYPE:
       TypeBinding leafType = castType.leafComponentType();
       if (isNarrowing && (leafType.isBoundParameterizedType() || leafType.isTypeVariable())) {
         this.bits |= ASTNode.UnsafeCast;
         return true;
       }
       break;
     case Binding.TYPE_PARAMETER:
       this.bits |= ASTNode.UnsafeCast;
       return true;
   }
   if (!isNarrowing
       && match
           == this.resolvedType
               .leafComponentType()) { // do not tag as unnecessary when recursing through upper
     // bounds
     tagAsUnnecessaryCast(scope, castType);
   }
   return true;
 }
  public TypeBinding resolveType(BlockScope scope) {

    this.constant = Constant.NotAConstant;
    if ((this.targetType = this.type.resolveType(scope, true /* check bounds*/)) == null)
      return null;

    /* https://bugs.eclipse.org/bugs/show_bug.cgi?id=320463
      https://bugs.eclipse.org/bugs/show_bug.cgi?id=312076
      JLS3 15.8.2 forbids the type named in the class literal expression from being a parameterized type.
      And the grammar in 18.1 disallows (where X and Y are some concrete types) constructs of the form
      Outer<X>.class, Outer<X>.Inner.class, Outer.Inner<X>.class, Outer<X>.Inner<Y>.class etc.
      Corollary wise, we should resolve the type of the class literal expression to be a raw type as
      class literals exist only for the raw underlying type.
    */
    LookupEnvironment environment = scope.environment();
    this.targetType =
        environment.convertToRawType(
            this.targetType, true /* force conversion of enclosing types*/);

    if (this.targetType.isArrayType()) {
      ArrayBinding arrayBinding = (ArrayBinding) this.targetType;
      TypeBinding leafComponentType = arrayBinding.leafComponentType;
      if (leafComponentType == TypeBinding.VOID) {
        scope.problemReporter().cannotAllocateVoidArray(this);
        return null;
      } else if (leafComponentType.isTypeVariable()) {
        scope
            .problemReporter()
            .illegalClassLiteralForTypeVariable((TypeVariableBinding) leafComponentType, this);
      }
    } else if (this.targetType.isTypeVariable()) {
      scope
          .problemReporter()
          .illegalClassLiteralForTypeVariable((TypeVariableBinding) this.targetType, this);
    }
    // {ObjectTeams: do we need a RoleClassLiteralAccess?
    if (this.targetType instanceof ReferenceBinding) {
      ReferenceBinding targetRef = (ReferenceBinding) this.targetType;
      if (targetRef.isRole()) {
        if (this.verbatim) {
          this.targetType =
              RoleTypeCreator.maybeWrapUnqualifiedRoleType(scope, this.targetType, this);
        } else {
          SourceTypeBinding site = scope.enclosingSourceType();
          if (scope.methodScope().isStatic // role class literal needs team instance
              && !site.isRole() // static role method are OK.
              && !RoleTypeBinding.isRoleWithExplicitAnchor(this.targetType)) // t.R.class?
          {
            scope.problemReporter().roleClassLiteralLacksTeamInstance(this, targetRef);
            return null;
          }
          ReferenceBinding teamBinding;
          if (RoleTypeBinding.isRoleWithExplicitAnchor(targetRef))
            teamBinding = targetRef.enclosingType();
          else teamBinding = TeamModel.findEnclosingTeamContainingRole(site, targetRef);
          if (teamBinding == null)
            scope.problemReporter().externalizedRoleClassLiteral(this, targetRef);
          else {
            TypeBinding methodType =
                RoleClassLiteralAccess.ensureGetClassMethod(
                    teamBinding.getTeamModel(),
                    targetRef.roleModel); // not affected by visibility check (for resilience)
            this.roleClassLiteralAccess = new RoleClassLiteralAccess(this, methodType);
            this.resolvedType = this.roleClassLiteralAccess.resolveType(scope);
          }
          return this.resolvedType;
        }
      }
    }
    // SH}
    ReferenceBinding classType = scope.getJavaLangClass();
    // https://bugs.eclipse.org/bugs/show_bug.cgi?id=328689
    if (scope.compilerOptions().sourceLevel >= ClassFileConstants.JDK1_5) {
      // Integer.class --> Class<Integer>, perform boxing of base types (int.class -->
      // Class<Integer>)
      TypeBinding boxedType = null;
      if (this.targetType.id == T_void) {
        boxedType = environment.getResolvedType(JAVA_LANG_VOID, scope);
      } else {
        boxedType = scope.boxing(this.targetType);
      }
      if (environment.usesNullTypeAnnotations())
        boxedType =
            environment.createAnnotatedType(
                boxedType, new AnnotationBinding[] {environment.getNonNullAnnotation()});
      this.resolvedType =
          environment.createParameterizedType(
              classType, new TypeBinding[] {boxedType}, null /*not a member*/);
    } else {
      this.resolvedType = classType;
    }
    return this.resolvedType;
  }