Number (@Nullable PsiExpression expression) { expression = PsiUtil.skipParenthesizedExprDown(expression); if (expression instanceof PsiLiteralExpression) { return tryCast(((PsiLiteralExpression)expression).getValue(), Number.class); } if (expression instanceof PsiUnaryExpression && ((PsiUnaryExpression)expression).getOperationTokenType().equals(JavaTokenType.MINUS)) { PsiExpression operand = ((PsiUnaryExpression)expression).getOperand(); if (operand instanceof PsiLiteralExpression) { Object value = ((PsiLiteralExpression)operand).getValue(); return negate(value); } } return null; }