bdlt_fixutilconfiguration.h

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/// @file bdlt_fixutilconfiguration.h
///
/// The content of this file has been pre-processed for Doxygen.
///
 
 
// bdlt_fixutilconfiguration.h                                        -*-C++-*-
#ifndef INCLUDED_BDLT_FIXUTILCONFIGURATION
#define INCLUDED_BDLT_FIXUTILCONFIGURATION
 
#include <bsls_ident.h>
BSLS_IDENT("$Id: $")
 
/// @defgroup bdlt_fixutilconfiguration bdlt_fixutilconfiguration
/// @brief  Provide an attribute class to configure FIX string generation.
/// @addtogroup bdl
/// @{
/// @addtogroup bdlt
/// @{
/// @addtogroup bdlt_fixutilconfiguration
/// @{
///
/// <h1> Outline </h1>
/// * <a href="#bdlt_fixutilconfiguration-purpose"> Purpose</a>
/// * <a href="#bdlt_fixutilconfiguration-classes"> Classes </a>
/// * <a href="#bdlt_fixutilconfiguration-description"> Description </a>
///   * <a href="#bdlt_fixutilconfiguration-attributes"> Attributes </a>
///   * <a href="#bdlt_fixutilconfiguration-default-configuration"> Default Configuration </a>
///   * <a href="#bdlt_fixutilconfiguration-usage"> Usage </a>
///     * <a href="#bdlt_fixutilconfiguration-example-1-configuring-fix-string-generation"> Example 1: Configuring FIX String Generation </a>
///     * <a href="#bdlt_fixutilconfiguration-example-2-setting-the-process-wide-default-configuration"> Example 2: Setting the Process-Wide Default Configuration </a>
///
/// # Purpose {#bdlt_fixutilconfiguration-purpose}
/// Provide an attribute class to configure FIX string generation.
///
/// # Classes {#bdlt_fixutilconfiguration-classes}
///
/// -  bdlt::FixUtilConfiguration: configuration for FIX strings
///
/// @see  bdlt_fixutil
///
/// # Description {#bdlt_fixutilconfiguration-description}
/// This component provides an unconstrained (value-semantic)
/// attribute class, `bdlt::FixUtilConfiguration`, that may be used to configure
/// various aspects of generated FIX strings.
///
/// ## Attributes {#bdlt_fixutilconfiguration-attributes}
///
///
/// @code
///            Name             Type   Default
/// -------------------------   ----   -------
/// fractionalSecondPrecision   int     3
/// useZAbbreviationForUtc      bool    false
/// @endcode
/// * `fractionalSecondPrecision`: number of digits used to represent
///   fractional seconds; must be in the range `0 .. 6`.
/// * `useZAbbreviationForUtc`: `true` if `Z` should be used for the timezone
///   offset instead of `+00:00` (specific to UTC).
///
/// ## Default Configuration {#bdlt_fixutilconfiguration-default-configuration}
///
///
/// This component also provides a (process-wide) default configuration that may
/// be set and retrieved via the `setDefaultConfiguration` and
/// `defaultConfiguration` class methods, respectively.  See Usage Example 2 for
/// further details.
///
/// ## Usage {#bdlt_fixutilconfiguration-usage}
///
///
/// This section illustrates intended use of this component.
///
/// ### Example 1: Configuring FIX String Generation {#bdlt_fixutilconfiguration-example-1-configuring-fix-string-generation}
///
///
/// This example demonstrates creation of a `bdlt::FixUtilConfiguration` object
/// that may be used to influence the format of the output produced by a
/// hypothetical utility, `my::FixUtil`, that generates and parses FIX strings
/// for `bdlt` vocabulary types (see @ref bdlt_fixutil , which provides just such
/// functionality).  In particular, suppose that given a sample
/// `bdlt::DatetimeTz` object:
/// @code
/// const bdlt::DatetimeTz datetimeTz(
///                            bdlt::Datetime(2005, 1, 31, 8, 59, 59, 123), 0);
/// @endcode
/// `my::FixUtil` produces, by default, the following string (which is a valid
/// FIX string):
/// @code
/// 20050131-08:59:59.123+00:00
/// @endcode
/// However, we would like to produce the following (also valid FIX) string
/// instead:
/// @code
/// 20050131-08:59:59.123000Z
/// @endcode
/// `bdlt::FixUtilConfiguration` can be used to obtain the desired result
/// assuming that `my::FixUtil` uses `bdlt::FixUtilConfiguration` to affect the
/// format of generated strings in this fashion (e.g., again see
/// @ref bdlt_fixutil ).
///
/// First, we construct a `bdlt::FixUtilConfiguration` object that has the
/// default value:
/// @code
/// bdlt::FixUtilConfiguration configuration;
/// assert( configuration.fractionalSecondPrecision() == 3);
/// assert(!configuration.useZAbbreviationForUtc());
/// @endcode
/// Then, we modify `configuration` to indicate that we want to use 6 digits of
/// precision in the fractional seconds:
/// @code
/// configuration.setFractionalSecondPrecision(6);
/// assert( configuration.fractionalSecondPrecision() == 6);
/// assert(!configuration.useZAbbreviationForUtc());
/// @endcode
/// Finally, we modify `configuration` to indicate that we want to use `Z` as an
/// abbreviation for UTC:
/// @code
/// configuration.setUseZAbbreviationForUtc(true);
/// assert( configuration.fractionalSecondPrecision() == 6);
/// assert( configuration.useZAbbreviationForUtc());
/// @endcode
/// Our `configuration` object can now be supplied to `my::FixUtil` to produce
/// the desired result.
///
/// ### Example 2: Setting the Process-Wide Default Configuration {#bdlt_fixutilconfiguration-example-2-setting-the-process-wide-default-configuration}
///
///
/// This example demonstrates how to establish the process-wide default
/// configuration.
///
/// First, we retrieve the default configuration in effect at process start-up
/// and note that it has the default-constructed value:
/// @code
/// bdlt::FixUtilConfiguration configuration =
///                         bdlt::FixUtilConfiguration::defaultConfiguration();
/// assert(bdlt::FixUtilConfiguration() == configuration);
/// assert( configuration.fractionalSecondPrecision() == 3);
/// assert(!configuration.useZAbbreviationForUtc());
/// @endcode
/// Next, we modify `configuration` to indicate that we want to output `Z` when
/// the timezone offset is UTC (i.e., instead of `+00:00`):
/// @code
/// configuration.setUseZAbbreviationForUtc(true);
/// assert( configuration.fractionalSecondPrecision() == 3);
/// assert( configuration.useZAbbreviationForUtc());
/// @endcode
/// Then, we modify `configuration` to display milliseconds:
/// @code
/// configuration.setFractionalSecondPrecision(6);
/// assert( configuration.fractionalSecondPrecision() == 6);
/// assert( configuration.useZAbbreviationForUtc());
/// @endcode
/// Now, we set the default configuration to the value of our `configuration`
/// object:
/// @code
/// bdlt::FixUtilConfiguration::setDefaultConfiguration(configuration);
/// @endcode
/// Finally, we verify that the default configuration was updated as expected:
/// @code
/// const bdlt::FixUtilConfiguration newConfiguration =
///                     bdlt::FixUtilConfiguration::defaultConfiguration();
/// assert( newConfiguration.fractionalSecondPrecision() == 6);
/// assert( newConfiguration.useZAbbreviationForUtc());
/// @endcode
/// Note that the expected usage is that the process-wide configuration will be
/// established *once*, early in `main`, and not changed throughout the lifetime
/// of a process.
/// @}
/** @} */
/** @} */
 
/** @addtogroup bdl
 * @{
 */
/** @addtogroup bdlt
 * @{
 */
/** @addtogroup bdlt_fixutilconfiguration
 * @{
 */
 
#include <bdlscm_version.h>
 
#include <bsls_assert.h>
#include <bsls_atomicoperations.h>
#include <bsls_review.h>
 
#include <bsl_iosfwd.h>
 
 
namespace bdlt {
 
                        // ==========================
                        // class FixUtilConfiguration
                        // ==========================
 
/// This unconstrained (value-semantic) attribute class characterizes how to
/// configure certain behavior in `FixUtil` functions.  Currently, only the
/// `generate` and `generateRaw` methods of that utility are affected by
/// `FixUtilConfiguration` settings.  See the Attributes section under
/// @DESCRIPTION in the component-level documentation for information on the
/// class attributes.
///
/// See @ref bdlt_fixutilconfiguration 
class FixUtilConfiguration {
 
  private:
    // PRIVATE TYPES
 
    /// This enumeration denotes the distinct bits that define the values of
    /// each of the two configuration attributes.
    enum {
        k_FRACTIONAL_SECOND_PRECISION_MASK = 0x07,
        k_USE_Z_ABBREVIATION_FOR_UTC_BIT   = 0x08
    };
 
    // CLASS DATA
    static bsls::AtomicOperations::AtomicTypes::Int
                     s_defaultConfiguration;  // process-wide configuration
 
    // DATA
    int              d_configurationMask;     // bitmask defining configuration
 
    // FRIENDS
    friend bool operator==(const FixUtilConfiguration&,
                           const FixUtilConfiguration&);
    friend bool operator!=(const FixUtilConfiguration&,
                           const FixUtilConfiguration&);
 
  private:
    // PRIVATE CREATORS
 
    /// Create a `FixUtilConfiguration` object having the value indicated by
    /// the specified `configurationMask`.  The behavior is undefined unless
    /// `configurationMask` represents a valid `FixUtilConfiguration` value.
    explicit FixUtilConfiguration(int configurationMask);
 
  public:
    // CLASS METHODS
 
    /// Return the value of the process-wide `FixUtilConfiguration` that is
    /// currently in effect.
    static FixUtilConfiguration defaultConfiguration();
 
    /// Set the value of the process-wide `FixUtilConfiguration` to the
    /// specified `configuration`.  Note that the expected usage is that the
    /// process-wide configuration will be established *once*, early in
    /// `main`, and not changed throughout the lifetime of a process.
    static void setDefaultConfiguration(
                                    const FixUtilConfiguration& configuration);
 
    // CREATORS
 
    /// Create a `FixUtilConfiguration` object having the (default)
    /// attribute values:
    /// @code
    /// fractionalSecondPrecision() == 3
    /// useZAbbreviationForUtc()    == false
    /// @endcode
    FixUtilConfiguration();
 
    /// Create a `FixUtilConfiguration` object having the value of the
    /// specified `original` configuration.
    FixUtilConfiguration(const FixUtilConfiguration& original);
 
    /// Destroy this object.
    ~FixUtilConfiguration();
 
    // MANIPULATORS
 
    /// Assign to this object the value of the specified `rhs`
    /// configuration, and return a reference providing modifiable access to
    /// this object.
    FixUtilConfiguration& operator=(const FixUtilConfiguration& rhs);
 
    /// Set the `fractionalSecondPrecision` attribute of this object to the
    /// specified `value`.  The behavior is undefined unless `0 <= value`
    /// and `6 >= value`.  Note that the FIX protocol allows for much higher
    /// precision.
    void setFractionalSecondPrecision(int value);
 
    /// Set the `useZAbbreviationForUtc` attribute of this object to the
    /// specified `value`.
    void setUseZAbbreviationForUtc(bool value);
 
    // ACCESSORS
 
    /// Return the value of the `fractionalSecondPrecision` attribute of
    /// this object.
    int fractionalSecondPrecision() const;
 
    /// Return the value of the `useZAbbreviationForUtc` attribute of this
    /// object.
    bool useZAbbreviationForUtc() const;
 
                                  // Aspects
 
    /// Write the value of this object to the specified output `stream` in a
    /// human-readable format, and return a reference to `stream`.
    /// Optionally specify an initial indentation `level`, whose absolute
    /// value is incremented recursively for nested objects.  If `level` is
    /// specified, optionally specify `spacesPerLevel`, whose absolute value
    /// indicates the number of spaces per indentation level for this and
    /// all of its nested objects.  If `level` is negative, suppress
    /// indentation of the first line.  If `spacesPerLevel` is negative,
    /// format the entire output on one line, suppressing all but the
    /// initial indentation (as governed by `level`).  If `stream` is not
    /// valid on entry, this operation has no effect.  Note that this
    /// human-readable format is not fully specified, and can change without
    /// notice.
    bsl::ostream& print(bsl::ostream& stream,
                        int           level = 0,
                        int           spacesPerLevel = 4) const;
};
 
// FREE OPERATORS
 
/// Return `true` if the specified `lhs` and `rhs` objects have the same
/// value, and `false` otherwise.  Two `FixUtilConfiguration` objects have
/// the same value if each of their `fractionalSecondPrecision` and
/// `useZAbbreviationForUtc` attributes (respectively) have the same value.
bool operator==(const FixUtilConfiguration& lhs,
                const FixUtilConfiguration& rhs);
 
/// Return `true` if the specified `lhs` and `rhs` objects do not have the
/// same value, and `false` otherwise.  Two `FixUtilConfiguration` objects
/// do not have the same value if any of their `fractionalSecondPrecision`
/// or `useZAbbreviationForUtc` attributes (respectively) do not have the
/// same value.
bool operator!=(const FixUtilConfiguration& lhs,
                const FixUtilConfiguration& rhs);
 
/// Write the value of the specified `object` to the specified output
/// `stream` in a single-line format, and return a reference to `stream`.
/// If `stream` is not valid on entry, this operation has no effect.  Note
/// that this human-readable format is not fully specified and can change
/// without notice.  Also note that this method has the same behavior as
/// `object.print(stream, 0, -1)`, but with the attribute names elided.
bsl::ostream& operator<<(bsl::ostream&               stream,
                         const FixUtilConfiguration& object);
 
// ============================================================================
//                             INLINE DEFINITIONS
// ============================================================================
 
                        // --------------------------
                        // class FixUtilConfiguration
                        // --------------------------
 
// PRIVATE CREATORS
inline
FixUtilConfiguration::FixUtilConfiguration(int configurationMask)
: d_configurationMask(configurationMask)
{
    BSLS_ASSERT(0 == (configurationMask
                           & ~(k_FRACTIONAL_SECOND_PRECISION_MASK
                             | k_USE_Z_ABBREVIATION_FOR_UTC_BIT)));
}
 
// CLASS METHODS
inline
FixUtilConfiguration FixUtilConfiguration::defaultConfiguration()
{
    return FixUtilConfiguration(
               bsls::AtomicOperations::getIntRelaxed(&s_defaultConfiguration));
}
 
inline
void FixUtilConfiguration::setDefaultConfiguration(
                                     const FixUtilConfiguration& configuration)
{
    bsls::AtomicOperations::setIntRelaxed(&s_defaultConfiguration,
                                          configuration.d_configurationMask);
}
 
// CREATORS
inline
FixUtilConfiguration::FixUtilConfiguration()
: d_configurationMask(3)
{
}
 
inline
FixUtilConfiguration::FixUtilConfiguration(
                                          const FixUtilConfiguration& original)
: d_configurationMask(original.d_configurationMask)
{
}
 
inline
FixUtilConfiguration::~FixUtilConfiguration()
{
    BSLS_ASSERT(0 == (d_configurationMask
                           & ~(k_FRACTIONAL_SECOND_PRECISION_MASK
                             | k_USE_Z_ABBREVIATION_FOR_UTC_BIT)));
}
 
// MANIPULATORS
inline
FixUtilConfiguration& FixUtilConfiguration::operator=(
                                               const FixUtilConfiguration& rhs)
{
    d_configurationMask = rhs.d_configurationMask;
 
    return *this;
}
 
// ACCESSORS
inline
int FixUtilConfiguration::fractionalSecondPrecision() const
{
    return d_configurationMask & k_FRACTIONAL_SECOND_PRECISION_MASK;
}
 
inline
bool FixUtilConfiguration::useZAbbreviationForUtc() const
{
    return d_configurationMask & k_USE_Z_ABBREVIATION_FOR_UTC_BIT;
}
 
}  // close package namespace
 
// FREE OPERATORS
inline
bool bdlt::operator==(const FixUtilConfiguration& lhs,
                      const FixUtilConfiguration& rhs)
{
    return lhs.d_configurationMask == rhs.d_configurationMask;
}
 
inline
bool bdlt::operator!=(const FixUtilConfiguration& lhs,
                      const FixUtilConfiguration& rhs)
{
    return lhs.d_configurationMask != rhs.d_configurationMask;
}
 
 
 
#endif
 
// ----------------------------------------------------------------------------
// Copyright 2016 Bloomberg Finance L.P.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// ----------------------------- END-OF-FILE ----------------------------------
 
/** @} */
/** @} */
/** @} */