@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;
        }
 private DfaValue popQualifier(
     MethodCallInstruction instruction, DataFlowRunner runner, DfaMemoryState memState) {
   @NotNull final DfaValue qualifier = memState.pop();
   boolean unboxing = instruction.getMethodType() == MethodCallInstruction.MethodType.UNBOXING;
   NullabilityProblem problem =
       unboxing ? NullabilityProblem.unboxingNullable : NullabilityProblem.callNPE;
   PsiExpression anchor = unboxing ? instruction.getContext() : instruction.getCallExpression();
   if (!checkNotNullable(memState, qualifier, problem, anchor)) {
     forceNotNull(runner, memState, qualifier);
   }
   return qualifier;
 }
  @NotNull
  private DfaValue getMethodResultValue(
      MethodCallInstruction instruction,
      @Nullable DfaValue qualifierValue,
      DfaValueFactory factory) {
    DfaValue precalculated = instruction.getPrecalculatedReturnValue();
    if (precalculated != null) {
      return precalculated;
    }

    final PsiType type = instruction.getResultType();
    final MethodCallInstruction.MethodType methodType = instruction.getMethodType();

    if (methodType == MethodCallInstruction.MethodType.UNBOXING) {
      return factory.getBoxedFactory().createUnboxed(qualifierValue);
    }

    if (methodType == MethodCallInstruction.MethodType.BOXING) {
      DfaValue boxed = factory.getBoxedFactory().createBoxed(qualifierValue);
      return boxed == null ? factory.createTypeValue(type, Nullness.NOT_NULL) : boxed;
    }

    if (methodType == MethodCallInstruction.MethodType.CAST) {
      assert qualifierValue != null;
      if (qualifierValue instanceof DfaConstValue) {
        Object casted =
            TypeConversionUtil.computeCastTo(((DfaConstValue) qualifierValue).getValue(), type);
        return factory
            .getConstFactory()
            .createFromValue(casted, type, ((DfaConstValue) qualifierValue).getConstant());
      }
      return qualifierValue;
    }

    if (type != null && (type instanceof PsiClassType || type.getArrayDimensions() > 0)) {
      Nullness nullability = myReturnTypeNullability.get(instruction);
      if (nullability == Nullness.UNKNOWN && factory.isUnknownMembersAreNullable()) {
        nullability = Nullness.NULLABLE;
      }
      return factory.createTypeValue(type, nullability);
    }
    return DfaUnknownValue.getInstance();
  }
  @Nullable
  private DfaValue[] popCallArguments(
      MethodCallInstruction instruction, DataFlowRunner runner, DfaMemoryState memState) {
    final PsiExpression[] args = instruction.getArgs();

    PsiMethod method = instruction.getTargetMethod();
    boolean varargCall = instruction.isVarArgCall();
    DfaValue[] argValues;
    if (method == null || instruction.getContracts().isEmpty()) {
      argValues = null;
    } else {
      int paramCount = method.getParameterList().getParametersCount();
      if (paramCount == args.length || method.isVarArgs() && args.length >= paramCount - 1) {
        argValues = new DfaValue[paramCount];
        if (varargCall) {
          argValues[paramCount - 1] = DfaUnknownValue.getInstance();
        }
      } else {
        argValues = null;
      }
    }

    for (int i = 0; i < args.length; i++) {
      final DfaValue arg = memState.pop();
      int paramIndex = args.length - i - 1;
      if (argValues != null && (paramIndex < argValues.length - 1 || !varargCall)) {
        argValues[paramIndex] = arg;
      }

      PsiExpression expr = args[paramIndex];
      Nullness requiredNullability = instruction.getArgRequiredNullability(expr);
      if (requiredNullability == Nullness.NOT_NULL) {
        if (!checkNotNullable(
            memState, arg, NullabilityProblem.passingNullableToNotNullParameter, expr)) {
          forceNotNull(runner, memState, arg);
        }
      } else if (requiredNullability == Nullness.UNKNOWN) {
        checkNotNullable(
            memState, arg, NullabilityProblem.passingNullableArgumentToNonAnnotatedParameter, expr);
      }
    }
    return argValues;
  }
 private DfaValue getDfaContractReturnValue(
     MethodContract contract, MethodCallInstruction instruction, DfaValueFactory factory) {
   switch (contract.returnValue) {
     case NULL_VALUE:
       return factory.getConstFactory().getNull();
     case NOT_NULL_VALUE:
       return factory.createTypeValue(instruction.getResultType(), Nullness.NOT_NULL);
     case TRUE_VALUE:
       return factory.getConstFactory().getTrue();
     case FALSE_VALUE:
       return factory.getConstFactory().getFalse();
     case THROW_EXCEPTION:
       return factory.getConstFactory().getContractFail();
     default:
       return getMethodResultValue(instruction, null, factory);
   }
 }
  @Override
  public DfaInstructionState[] visitMethodCall(
      final MethodCallInstruction instruction,
      final DataFlowRunner runner,
      final DfaMemoryState memState) {
    DfaValue[] argValues = popCallArguments(instruction, runner, memState);
    final DfaValue qualifier = popQualifier(instruction, runner, memState);

    List<DfaMemoryState> currentStates = ContainerUtil.newArrayList(memState);
    Set<DfaMemoryState> finalStates = ContainerUtil.newLinkedHashSet();
    if (argValues != null) {
      for (MethodContract contract : instruction.getContracts()) {
        currentStates =
            addContractResults(
                argValues, contract, currentStates, instruction, runner.getFactory(), finalStates);
      }
    }
    for (DfaMemoryState state : currentStates) {
      state.push(getMethodResultValue(instruction, qualifier, runner.getFactory()));
      finalStates.add(state);
    }

    return ContainerUtil.map2Array(
        finalStates,
        DfaInstructionState.class,
        new Function<DfaMemoryState, DfaInstructionState>() {
          @Override
          public DfaInstructionState fun(DfaMemoryState state) {
            if (instruction.shouldFlushFields()) {
              state.flushFields();
            }
            return new DfaInstructionState(
                runner.getInstruction(instruction.getIndex() + 1), state);
          }
        });
  }