/**
  * Determines whether apparent unnecessary cast wasn't actually used to perform return type
  * inference of generic method invocation or boxing.
  */
 private boolean isIndirectlyUsed() {
   if (this.expression instanceof MessageSend) {
     MethodBinding method = ((MessageSend) this.expression).binding;
     if (method instanceof ParameterizedGenericMethodBinding
         && ((ParameterizedGenericMethodBinding) method).inferredReturnType) {
       if (this.expectedType == null) return true;
       if (TypeBinding.notEquals(this.resolvedType, this.expectedType)) return true;
     }
   }
   if (this.expectedType != null
       && this.resolvedType.isBaseType()
       && !this.resolvedType.isCompatibleWith(this.expectedType)) {
     // boxing: Short s = (short) _byte
     return true;
   }
   return false;
 }
 /**
  * Cast expression code generation
  *
  * @param currentScope org.aspectj.org.eclipse.jdt.internal.compiler.lookup.BlockScope
  * @param codeStream org.aspectj.org.eclipse.jdt.internal.compiler.codegen.CodeStream
  * @param valueRequired boolean
  */
 public void generateCode(BlockScope currentScope, CodeStream codeStream, boolean valueRequired) {
   int pc = codeStream.position;
   boolean annotatedCast = (this.type.bits & ASTNode.HasTypeAnnotations) != 0;
   boolean needRuntimeCheckcast = (this.bits & ASTNode.GenerateCheckcast) != 0;
   if (this.constant != Constant.NotAConstant) {
     if (valueRequired
         || needRuntimeCheckcast
         || annotatedCast) { // Added for: 1F1W9IG: IVJCOM:WINNT - Compiler omits casting check
       codeStream.generateConstant(this.constant, this.implicitConversion);
       if (needRuntimeCheckcast || annotatedCast) {
         codeStream.checkcast(this.type, this.resolvedType);
       }
       if (!valueRequired) {
         // the resolveType cannot be double or long
         codeStream.pop();
       }
     }
     codeStream.recordPositionsFrom(pc, this.sourceStart);
     return;
   }
   this.expression.generateCode(
       currentScope, codeStream, annotatedCast || valueRequired || needRuntimeCheckcast);
   if (annotatedCast
       || (needRuntimeCheckcast
           && TypeBinding.notEquals(
               this.expression.postConversionType(currentScope),
               this.resolvedType
                   .erasure()))) { // no need to issue a checkcast if already done as genericCast
     codeStream.checkcast(this.type, this.resolvedType);
   }
   if (valueRequired) {
     codeStream.generateImplicitConversion(this.implicitConversion);
   } else if (annotatedCast || needRuntimeCheckcast) {
     switch (this.resolvedType.id) {
       case T_long:
       case T_double:
         codeStream.pop2();
         break;
       default:
         codeStream.pop();
         break;
     }
   }
   codeStream.recordPositionsFrom(pc, this.sourceStart);
 }
  public TypeBinding resolveType(BlockScope scope) {
    // compute a new constant if the cast is effective

    this.constant = Constant.NotAConstant;
    this.implicitConversion = TypeIds.T_undefined;

    boolean exprContainCast = false;

    TypeBinding castType = this.resolvedType = this.type.resolveType(scope);
    if (scope.compilerOptions().sourceLevel >= ClassFileConstants.JDK1_8) {
      this.expression.setExpressionContext(CASTING_CONTEXT);
      if (this.expression instanceof FunctionalExpression) {
        this.expression.setExpectedType(this.resolvedType);
        this.bits |= ASTNode.DisableUnnecessaryCastCheck;
      }
    }
    if (this.expression instanceof CastExpression) {
      this.expression.bits |= ASTNode.DisableUnnecessaryCastCheck;
      exprContainCast = true;
    }
    TypeBinding expressionType = this.expression.resolveType(scope);
    if (this.expression instanceof MessageSend) {
      MessageSend messageSend = (MessageSend) this.expression;
      MethodBinding methodBinding = messageSend.binding;
      if (methodBinding != null && methodBinding.isPolymorphic()) {
        messageSend.binding =
            scope
                .environment()
                .updatePolymorphicMethodReturnType(
                    (PolymorphicMethodBinding) methodBinding, castType);
        if (TypeBinding.notEquals(expressionType, castType)) {
          expressionType = castType;
          this.bits |= ASTNode.DisableUnnecessaryCastCheck;
        }
      }
    }
    if (castType != null) {
      if (expressionType != null) {

        boolean nullAnnotationMismatch =
            scope.compilerOptions().isAnnotationBasedNullAnalysisEnabled
                && NullAnnotationMatching.analyse(castType, expressionType, -1).isAnyMismatch();

        boolean isLegal =
            checkCastTypesCompatibility(scope, castType, expressionType, this.expression);
        if (isLegal) {
          this.expression.computeConversion(scope, castType, expressionType);
          if ((this.bits & ASTNode.UnsafeCast) != 0) { // unsafe cast
            if (scope.compilerOptions().reportUnavoidableGenericTypeProblems
                || !(expressionType.isRawType()
                    && this.expression.forcedToBeRaw(scope.referenceContext()))) {
              scope.problemReporter().unsafeCast(this, scope);
            }
          } else if (nullAnnotationMismatch) {
            // report null annotation issue at medium priority
            scope.problemReporter().unsafeNullnessCast(this, scope);
          } else {
            if (castType.isRawType()
                && scope.compilerOptions().getSeverity(CompilerOptions.RawTypeReference)
                    != ProblemSeverities.Ignore) {
              scope.problemReporter().rawTypeReference(this.type, castType);
            }
            if ((this.bits & (ASTNode.UnnecessaryCast | ASTNode.DisableUnnecessaryCastCheck))
                == ASTNode.UnnecessaryCast) { // unnecessary cast
              if (!isIndirectlyUsed()) // used for generic type inference or boxing ?
              scope.problemReporter().unnecessaryCast(this);
            }
          }
        } else { // illegal cast
          if ((castType.tagBits & TagBits.HasMissingType) == 0) { // no complaint if secondary error
            scope.problemReporter().typeCastError(this, castType, expressionType);
          }
          this.bits |= ASTNode.DisableUnnecessaryCastCheck; // disable further secondary diagnosis
        }
      }
      this.resolvedType =
          castType.capture(
              scope,
              this.type.sourceStart,
              this.type.sourceEnd); // make it unique, a cast expression shares source end with the
      // expression.
      if (exprContainCast) {
        checkNeedForCastCast(scope, this);
      }
    }
    return this.resolvedType;
  }
  private static void checkAlternateBinding(
      BlockScope scope,
      Expression receiver,
      TypeBinding receiverType,
      MethodBinding binding,
      Expression[] arguments,
      TypeBinding[] originalArgumentTypes,
      TypeBinding[] alternateArgumentTypes,
      final InvocationSite invocationSite) {
    InvocationSite fakeInvocationSite =
        new InvocationSite() {
          public TypeBinding[] genericTypeArguments() {
            return null;
          }

          public boolean isSuperAccess() {
            return invocationSite.isSuperAccess();
          }

          public boolean isTypeAccess() {
            return invocationSite.isTypeAccess();
          }

          public void setActualReceiverType(ReferenceBinding actualReceiverType) {
            /* ignore */
          }

          public void setDepth(int depth) {
            /* ignore */
          }

          public void setFieldIndex(int depth) {
            /* ignore */
          }

          public int sourceStart() {
            return 0;
          }

          public int sourceEnd() {
            return 0;
          }

          public TypeBinding invocationTargetType() {
            return invocationSite.invocationTargetType();
          }

          public boolean receiverIsImplicitThis() {
            return invocationSite.receiverIsImplicitThis();
          }

          public InferenceContext18 freshInferenceContext(Scope someScope) {
            return invocationSite.freshInferenceContext(someScope);
          }

          public ExpressionContext getExpressionContext() {
            return invocationSite.getExpressionContext();
          }

          public boolean isQualifiedSuper() {
            return invocationSite.isQualifiedSuper();
          }

          public boolean checkingPotentialCompatibility() {
            return false;
          }

          public void acceptPotentiallyCompatibleMethods(MethodBinding[] methods) {
            /* ignore */
          }
        };
    MethodBinding bindingIfNoCast;
    if (binding.isConstructor()) {
      bindingIfNoCast =
          scope.getConstructor(
              (ReferenceBinding) receiverType, alternateArgumentTypes, fakeInvocationSite);
    } else {
      bindingIfNoCast =
          receiver.isImplicitThis()
              ? scope.getImplicitMethod(
                  binding.selector, alternateArgumentTypes, fakeInvocationSite)
              : scope.getMethod(
                  receiverType, binding.selector, alternateArgumentTypes, fakeInvocationSite);
    }
    if (bindingIfNoCast == binding) {
      int argumentLength = originalArgumentTypes.length;
      if (binding.isVarargs()) {
        int paramLength = binding.parameters.length;
        if (paramLength == argumentLength) {
          int varargsIndex = paramLength - 1;
          ArrayBinding varargsType = (ArrayBinding) binding.parameters[varargsIndex];
          TypeBinding lastArgType = alternateArgumentTypes[varargsIndex];
          // originalType may be compatible already, but cast mandated
          // to clarify between varargs/non-varargs call
          if (varargsType.dimensions != lastArgType.dimensions()) {
            return;
          }
          if (lastArgType.isCompatibleWith(varargsType.elementsType())
              && lastArgType.isCompatibleWith(varargsType)) {
            return;
          }
        }
      }
      for (int i = 0; i < argumentLength; i++) {
        if (TypeBinding.notEquals(originalArgumentTypes[i], alternateArgumentTypes[i])
        /*&& !originalArgumentTypes[i].needsUncheckedConversion(alternateArgumentTypes[i])*/ ) {
          scope.problemReporter().unnecessaryCast((CastExpression) arguments[i]);
        }
      }
    }
  }