rippled/modules/beast_core/containers/beast_NamedValueSet.h

//------------------------------------------------------------------------------
/*
    This file is part of Beast: https://github.com/vinniefalco/Beast
    Copyright 2013, Vinnie Falco <vinnie.falco@gmail.com>

    Portions of this file are from JUCE.
    Copyright (c) 2013 - Raw Material Software Ltd.
    Please visit http://www.juce.com

    Permission to use, copy, modify, and/or distribute this software for any
    purpose  with  or without fee is hereby granted, provided that the above
    copyright notice and this permission notice appear in all copies.

    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
    ANY  SPECIAL ,  DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
//==============================================================================

#ifndef BEAST_NAMEDVALUESET_H_INCLUDED
#define BEAST_NAMEDVALUESET_H_INCLUDED

class XmlElement;
#ifndef DOXYGEN
 class JSONFormatter;
#endif


//==============================================================================
/** Holds a set of named var objects.

    This can be used as a basic structure to hold a set of var object, which can
    be retrieved by using their identifier.
*/
class BEAST_API NamedValueSet
{
public:
    /** Creates an empty set. */
    NamedValueSet() noexcept;

    /** Creates a copy of another set. */
    NamedValueSet (const NamedValueSet& other);

    /** Replaces this set with a copy of another set. */
    NamedValueSet& operator= (const NamedValueSet& other);

   #if BEAST_COMPILER_SUPPORTS_MOVE_SEMANTICS
    NamedValueSet (NamedValueSet&& other) noexcept;
    NamedValueSet& operator= (NamedValueSet&& other) noexcept;
   #endif

    /** Destructor. */
    ~NamedValueSet();

    bool operator== (const NamedValueSet& other) const;
    bool operator!= (const NamedValueSet& other) const;

    //==============================================================================
    /** Returns the total number of values that the set contains. */
    int size() const noexcept;

    /** Returns the value of a named item.
        If the name isn't found, this will return a void variant.
        @see getProperty
    */
    const var& operator[] (const Identifier name) const;

    /** Tries to return the named value, but if no such value is found, this will
        instead return the supplied default value.
    */
    var getWithDefault (const Identifier name, const var& defaultReturnValue) const;

    /** Changes or adds a named value.
        @returns    true if a value was changed or added; false if the
                    value was already set the the value passed-in.
    */
    bool set (const Identifier name, const var& newValue);

   #if BEAST_COMPILER_SUPPORTS_MOVE_SEMANTICS
    /** Changes or adds a named value.
        @returns    true if a value was changed or added; false if the
                    value was already set the the value passed-in.
    */
    bool set (const Identifier name, var&& newValue);
   #endif

    /** Returns true if the set contains an item with the specified name. */
    bool contains (const Identifier name) const;

    /** Removes a value from the set.
        @returns    true if a value was removed; false if there was no value
                    with the name that was given.
    */
    bool remove (const Identifier name);

    /** Returns the name of the value at a given index.
        The index must be between 0 and size() - 1.
    */
    const Identifier getName (int index) const;

    /** Returns the value of the item at a given index.
        The index must be between 0 and size() - 1.
    */
    const var& getValueAt (int index) const;

    /** Removes all values. */
    void clear();

    //==============================================================================
    /** Returns a pointer to the var that holds a named value, or null if there is
        no value with this name.

        Do not use this method unless you really need access to the internal var object
        for some reason - for normal reading and writing always prefer operator[]() and set().
    */
    var* getVarPointer (const Identifier name) const noexcept;

    //==============================================================================
    /** Sets properties to the values of all of an XML element's attributes. */
    void setFromXmlAttributes (const XmlElement& xml);

    /** Sets attributes in an XML element corresponding to each of this object's
        properties.
    */
    void copyToXmlAttributes (XmlElement& xml) const;

private:
    //==============================================================================
    class NamedValue : LeakChecked <NamedValue>
    {
    public:
        NamedValue() noexcept;
        NamedValue (const NamedValue&);
        NamedValue (const Identifier name, const var& value);
        NamedValue& operator= (const NamedValue&);
       #if BEAST_COMPILER_SUPPORTS_MOVE_SEMANTICS
        NamedValue (NamedValue&&) noexcept;
        NamedValue (const Identifier name, var&& value);
        NamedValue& operator= (NamedValue&&) noexcept;
       #endif
        bool operator== (const NamedValue& other) const noexcept;

        LinkedListPointer<NamedValue> nextListItem;
        Identifier name;
        var value;

    private:
    };

    friend class LinkedListPointer<NamedValue>;
    LinkedListPointer<NamedValue> values;

    friend class JSONFormatter;
};


#endif   // BEAST_NAMEDVALUESET_H_INCLUDED