1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>Class template basic_direct_mapping</title> 5<link rel="stylesheet" href="../../../../../../../doc/src/boostbook.css" type="text/css"> 6<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 7<link rel="home" href="../../../index.html" title="Chapter 1. Boost.Log v2"> 8<link rel="up" href="../../../sinks.html#header.boost.log.sinks.attribute_mapping_hpp" title="Header <boost/log/sinks/attribute_mapping.hpp>"> 9<link rel="prev" href="basic_custom_mapping.html" title="Class template basic_custom_mapping"> 10<link rel="next" href="basic_mapping.html" title="Struct template basic_mapping"> 11</head> 12<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 13<table cellpadding="2" width="100%"><tr><td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../../../../boost.png"></td></tr></table> 14<hr> 15<div class="spirit-nav"> 16<a accesskey="p" href="basic_custom_mapping.html"><img src="../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../../sinks.html#header.boost.log.sinks.attribute_mapping_hpp"><img src="../../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../index.html"><img src="../../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="basic_mapping.html"><img src="../../../../../../../doc/src/images/next.png" alt="Next"></a> 17</div> 18<div class="refentry"> 19<a name="boost.log.sinks.basic_direct_mapping"></a><div class="titlepage"></div> 20<div class="refnamediv"> 21<h2><span class="refentrytitle">Class template basic_direct_mapping</span></h2> 22<p>boost::log::sinks::basic_direct_mapping — Straightforward mapping. </p> 23</div> 24<h2 xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv-title">Synopsis</h2> 25<div xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv"><pre class="synopsis"><span class="comment">// In header: <<a class="link" href="../../../sinks.html#header.boost.log.sinks.attribute_mapping_hpp" title="Header <boost/log/sinks/attribute_mapping.hpp>">boost/log/sinks/attribute_mapping.hpp</a>> 26 27</span><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> MappedT<span class="special">,</span> <span class="keyword">typename</span> AttributeValueT <span class="special">=</span> <span class="keyword">int</span><span class="special">></span> 28<span class="keyword">class</span> <a class="link" href="basic_direct_mapping.html" title="Class template basic_direct_mapping">basic_direct_mapping</a> <span class="special">:</span> 29 <span class="keyword">public</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">log</span><span class="special">::</span><span class="identifier">sinks</span><span class="special">::</span><span class="identifier">basic_mapping</span><span class="special"><</span> <span class="identifier">MappedT</span> <span class="special">></span> 30<span class="special">{</span> 31<span class="keyword">public</span><span class="special">:</span> 32 <span class="comment">// types</span> 33 <span class="keyword">typedef</span> <span class="identifier">AttributeValueT</span> <a name="boost.log.sinks.basic_direct_mapping.attribute_value_type"></a><span class="identifier">attribute_value_type</span><span class="special">;</span> <span class="comment">// Attribute contained value type. </span> 34 <span class="keyword">typedef</span> <span class="identifier">base_type</span><span class="special">::</span><span class="identifier">mapped_type</span> <a name="boost.log.sinks.basic_direct_mapping.mapped_type"></a><span class="identifier">mapped_type</span><span class="special">;</span> <span class="comment">// Mapped value type. </span> 35 36 <span class="comment">// <a class="link" href="basic_direct_mapping.html#boost.log.sinks.basic_direct_mappingconstruct-copy-destruct">construct/copy/destruct</a></span> 37 <span class="keyword">explicit</span> <a class="link" href="basic_direct_mapping.html#idm46079576931952-bb"><span class="identifier">basic_direct_mapping</span></a><span class="special">(</span><span class="identifier">attribute_name</span> <span class="keyword">const</span> <span class="special">&</span><span class="special">,</span> <span class="identifier">mapped_type</span> <span class="keyword">const</span> <span class="special">&</span><span class="special">)</span><span class="special">;</span> 38 39 <span class="comment">// <a class="link" href="basic_direct_mapping.html#idm46079576936208-bb">public member functions</a></span> 40 <span class="identifier">mapped_type</span> <a class="link" href="basic_direct_mapping.html#idm46079576935648-bb"><span class="keyword">operator</span><span class="special">(</span><span class="special">)</span></a><span class="special">(</span><span class="identifier">record_view</span> <span class="keyword">const</span> <span class="special">&</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 41<span class="special">}</span><span class="special">;</span></pre></div> 42<div class="refsect1"> 43<a name="idm44984865765056"></a><h2>Description</h2> 44<p>This type of mapping assumes that attribute with a particular name always provides values that map directly onto the native values. The mapping simply returns the extracted attribute value converted to the native value. </p> 45<div class="refsect2"> 46<a name="idm44984865764144"></a><h3> 47<a name="boost.log.sinks.basic_direct_mappingconstruct-copy-destruct"></a><code class="computeroutput">basic_direct_mapping</code> 48 public 49 construct/copy/destruct</h3> 50<div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"> 51<pre class="literallayout"><span class="keyword">explicit</span> <a name="idm46079576931952-bb"></a><span class="identifier">basic_direct_mapping</span><span class="special">(</span><span class="identifier">attribute_name</span> <span class="keyword">const</span> <span class="special">&</span> name<span class="special">,</span> 52 <span class="identifier">mapped_type</span> <span class="keyword">const</span> <span class="special">&</span> default_value<span class="special">)</span><span class="special">;</span></pre> 53<p>Constructor</p> 54<p> 55</p> 56<div class="variablelist"><table border="0" class="variablelist compact"> 57<colgroup> 58<col align="left" valign="top"> 59<col> 60</colgroup> 61<tbody><tr> 62<td><p><span class="term">Parameters:</span></p></td> 63<td><div class="variablelist"><table border="0" class="variablelist compact"> 64<colgroup> 65<col align="left" valign="top"> 66<col> 67</colgroup> 68<tbody> 69<tr> 70<td><p><span class="term"><code class="computeroutput">default_value</code></span></p></td> 71<td><p>The default native value that is returned if the attribute value is not found </p></td> 72</tr> 73<tr> 74<td><p><span class="term"><code class="computeroutput">name</code></span></p></td> 75<td><p>Attribute name </p></td> 76</tr> 77</tbody> 78</table></div></td> 79</tr></tbody> 80</table></div> 81</li></ol></div> 82</div> 83<div class="refsect2"> 84<a name="idm44984865747856"></a><h3> 85<a name="idm46079576936208-bb"></a><code class="computeroutput">basic_direct_mapping</code> public member functions</h3> 86<div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"> 87<pre class="literallayout"><span class="identifier">mapped_type</span> <a name="idm46079576935648-bb"></a><span class="keyword">operator</span><span class="special">(</span><span class="special">)</span><span class="special">(</span><span class="identifier">record_view</span> <span class="keyword">const</span> <span class="special">&</span> rec<span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre> 88<p>Extraction operator</p> 89<p> 90 91</p> 92<div class="variablelist"><table border="0" class="variablelist compact"> 93<colgroup> 94<col align="left" valign="top"> 95<col> 96</colgroup> 97<tbody> 98<tr> 99<td><p><span class="term">Parameters:</span></p></td> 100<td><div class="variablelist"><table border="0" class="variablelist compact"> 101<colgroup> 102<col align="left" valign="top"> 103<col> 104</colgroup> 105<tbody><tr> 106<td><p><span class="term"><code class="computeroutput">rec</code></span></p></td> 107<td><p>A log record to extract value from </p></td> 108</tr></tbody> 109</table></div></td> 110</tr> 111<tr> 112<td><p><span class="term">Returns:</span></p></td> 113<td><p>An extracted attribute value </p></td> 114</tr> 115</tbody> 116</table></div> 117</li></ol></div> 118</div> 119</div> 120</div> 121<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 122<td align="left"></td> 123<td align="right"><div class="copyright-footer">Copyright © 2007-2019 Andrey Semashev<p> 124 Distributed under the Boost Software License, Version 1.0. (See accompanying 125 file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>). 126 </p> 127</div></td> 128</tr></table> 129<hr> 130<div class="spirit-nav"> 131<a accesskey="p" href="basic_custom_mapping.html"><img src="../../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../../sinks.html#header.boost.log.sinks.attribute_mapping_hpp"><img src="../../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../../index.html"><img src="../../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="basic_mapping.html"><img src="../../../../../../../doc/src/images/next.png" alt="Next"></a> 132</div> 133</body> 134</html> 135
