FieldValueRef.h

Go to the documentation of this file.

/*
* Copyright Onix Solutions Limited [OnixS]. All rights reserved.
*
* This software owned by Onix Solutions Limited [OnixS] and is protected by copyright law
* and international copyright treaties.
*
* Access to and use of the software is governed by the terms of the applicable OnixS Software
* Services Agreement (the Agreement) and Customer end user license agreements granting
* a non-assignable, non-transferable and non-exclusive license to use the software
* for it's own data processing purposes under the terms defined in the Agreement.
*
* Except as otherwise granted within the terms of the Agreement, copying or reproduction of any part
* of this source code or associated reference material to any other location for further reproduction
* or redistribution, and any amendments to this copyright notice, are expressly prohibited.
*
* Any reproduction or redistribution for sale or hiring of the Software not in accordance with
* the terms of the Agreement is a violation of copyright law.
*/

#pragma once

#include <OnixS/Eurex/MarketData/Numeric.h>
#include <OnixS/Eurex/MarketData/StringRef.h>
#include <OnixS/Eurex/MarketData/Timestamp.h>

namespace OnixS
{
    namespace Eurex
    {
        namespace MarketData
        {

            ONIXS_EUREX_EMDI_API_DECL (class, Message);
            ONIXS_EUREX_EMDI_API_DECL (class, Group);

            /// Implements concept of a read-only
            /// reference to a FIX field value.
            class
                ONIXS_EUREX_EMDI_API
                FieldValueRef
            {
                public:
                    /// Uninitialized value.
                    FieldValueRef();

                    /// Shallow copy from another one.
                    FieldValueRef (const FieldValueRef& other);

                    /// Indicated whether the instance
                    /// refers to a valid value.
                    operator bool() const;

                    /// Return string presentation
                    /// of the value being referenced.
                    operator std::string() const;

                    /// Compares with another instance for equality.
                    bool operator == (const FieldValueRef&) const;

                    /// Compares with another instance for inequality.
                    bool operator != (const FieldValueRef&) const;

                    /// Compares string presentation for
                    /// equality with given text reference.
                    bool operator == (const StringRef&) const;

                    /// Compares string presentation for
                    /// equality with given text reference.
                    bool operator != (const StringRef&) const;

                    /// Converts field value into whole number.
                    ///
                    /// @return false if conversion fails.
                    ///
                    /// @warning Due to performance considerations
                    /// doesn't check whether instance refers to a valid
                    /// value. Use OnixS::FIX::FieldValueRef::operator bool()
                    /// member to check instance for a validness.
                    bool toNumber (Int32&) const;

                    /// Converts field value into whole number.
                    ///
                    /// @return false if conversion fails.
                    ///
                    /// @warning Due to performance considerations
                    /// doesn't check whether instance refers to a valid
                    /// value. Use OnixS::FIX::FieldValueRef::operator bool()
                    /// member to check instance for a validness.
                    bool toNumber (UInt32&) const;

                    /// Converts field value into whole number.
                    ///
                    /// @return false if conversion fails.
                    ///
                    /// @warning Due to performance considerations
                    /// doesn't check whether instance refers to a valid
                    /// value. Use OnixS::FIX::FieldValueRef::operator bool()
                    /// member to check instance for a validness.
                    bool toNumber (Int64&) const;

                    /// Converts field value into whole number.
                    ///
                    /// @return false if conversion fails.
                    ///
                    /// @warning Due to performance considerations
                    /// doesn't check whether instance refers to a valid
                    /// value. Use OnixS::FIX::FieldValueRef::operator bool()
                    /// member to check instance for a validness.
                    bool toNumber (UInt64&) const;

                    /// Converts field value into floating point value.
                    ///
                    /// @return false if conversion fails.
                    ///
                    /// @warning Due to performance considerations
                    /// doesn't check whether instance refers to a valid
                    /// value. Use OnixS::FIX::FieldValueRef::operator bool()
                    /// member to check instance for a validness.
                    bool toNumber (Decimal&) const;

                    /// Converts field value into timestamp of requested format.
                    ///
                    /// @return false if conversion fails.
                    ///
                    /// @warning Due to performance considerations
                    /// doesn't check whether instance refers to a valid
                    /// value. Use OnixS::FIX::FieldValueRef::operator bool()
                    /// member to check instance for a validness.
                    bool
                    toTimestamp (
                        Timestamp&,
                        TimestampFormat::Enum =
                            TimestampFormat::YYYYMMDDHHMMSSNsec) const;

                    /// If value represents text, returns reference to it.
                    ///
                    /// @return false if conversion fails (for example,
                    /// stored value is whole number assigned to a field
                    /// using OnixS::FIX::FieldSet::setV member).
                    ///
                    /// @warning Due to performance considerations
                    /// doesn't check whether instance refers to a valid
                    /// value. Use OnixS::FIX::FieldValueRef::operator bool()
                    /// member to check instance for a validness.
                    bool toStringRef (StringRef&) const;

                    /// If value represent one-char text,
                    /// copies it into given variable.
                    ///
                    /// @return false if conversion fails (for example,
                    /// stored value is whole number assigned to a field
                    /// using OnixS::FIX::FieldSet::setV member).
                    ///
                    /// @warning Due to performance considerations
                    /// doesn't check whether instance refers to a valid
                    /// value. Use OnixS::FIX::FieldValueRef::operator bool()
                    /// member to check instance for a validness.
                    bool toChar (char&) const;

                    /// If repeating group is associated with
                    /// field, allows to get instance of it.
                    ///
                    /// @return false if no group is associated with field.
                    ///
                    /// @warning Due to performance considerations
                    /// doesn't check whether instance refers to a valid
                    /// value. Use OnixS::FIX::FieldValueRef::operator bool()
                    /// member to check instance for a validness.
                    bool toGroup (Group&) const;

                    /// Appends copy of text presentation to the std::string.
                    void toString (std::string&) const;

                    /// Return string presentation of field value.
                    std::string toString() const;

                    /// Updates instance to refer to another field value.
                    /// @warning Does NOT perform deep copy of field values.
                    /// Just updates reference to point to value of other field.
                    FieldValueRef& operator = (const FieldValueRef&);

                    ///
                    void swap(FieldValueRef&) throw();

                private:
                    friend class MessageOperator;

                    const void* impl_;

                    const Message* container_;

                    FieldValueRef (
                        const Message*,
                        const void*);
            };

            inline
            FieldValueRef::
            operator std::string() const
            {
                std::string str;

                toString (str);

                return str;
            }

            inline
            std::string
            FieldValueRef::toString() const
            {
                std::string str;

                toString (str);

                return str;
            }

            // More comparison operators.

            inline
            bool
            operator == (
                const FieldValueRef& ref,
                const std::string& str)
            {
                return ref == StringRef (str);
            }

            inline
            bool
            operator != (
                const FieldValueRef& ref,
                const std::string& str)
            {
                return ref != StringRef (str);
            }

            inline
            bool
            operator == (
                const std::string& str,
                const FieldValueRef& ref)
            {
                return ref == StringRef (str);
            }

            inline
            bool
            operator != (
                const std::string& str,
                const FieldValueRef& ref)
            {
                return ref != StringRef (str);
            }

            // More comparison operators.

            inline
            bool
            operator == (
                const FieldValueRef& ref,
                const char* str)
            {
                return ref == StringRef (str);
            }

            inline
            bool
            operator != (
                const FieldValueRef& ref,
                const char* str)
            {
                return ref != StringRef (str);
            }

            inline
            bool
            operator == (
                const char* str,
                const FieldValueRef& ref)
            {
                return ref == StringRef (str);
            }

            inline
            bool
            operator != (
                const char* str,
                const FieldValueRef& ref)
            {
                return ref != StringRef (str);
            }
        }
    }
}