1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>Why not using hierarchy of loggers, like in log4j? Why not Boost.Log4j? Etc.</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="../rationale.html" title="Rationale and FAQ"> 9<link rel="prev" href="why_not_lazy_streaming.html" title="Why not using lazy streaming?"> 10<link rel="next" href="fork_support.html" title="Does Boost.Log support process forking?"> 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="why_not_lazy_streaming.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../rationale.html"><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="fork_support.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a> 17</div> 18<div class="section"> 19<div class="titlepage"><div><div><h3 class="title"> 20<a name="log.rationale.why_not_log4j"></a><a class="link" href="why_not_log4j.html" title="Why not using hierarchy of loggers, like in log4j? Why not Boost.Log4j? Etc.">Why not using hierarchy 21 of loggers, like in log4j? Why not Boost.Log4j? Etc.</a> 22</h3></div></div></div> 23<p> 24 There are enough <a href="http://logging.apache.org/log4j/" target="_top">log4j</a>-like 25 libraries available for C++ already (see <a href="http://logging.apache.org/log4cxx/" target="_top">here</a>, 26 <a href="http://log4cplus.sourceforge.net/" target="_top">here</a> and <a href="http://log4cpp.sourceforge.net/" target="_top">here</a>), 27 so there is no point in implementing yet another one. Instead, this library 28 was aimed to solve more complex tasks, including ones that do not directly 29 fall under the common definition of "logging" term as a debugging 30 tool. Additionally, as Boost.Log was to be a generic library, it had to provide 31 more ways of extending itself, while keeping performance as high as possible. 32 Log4j concept seemed too limiting and inappropriate for these tasks and therefore 33 was rejected. 34 </p> 35<p> 36 As for hierarchical loggers, there is no need for this feature in the current 37 library design. One of the main benefits it provides in log4j is determining 38 the appenders (sinks, in terms of this library) in which a log record will 39 end up. This library achieves the same result by filtering. The other application 40 of this feature in Boost.Log could be that the loggers in the hierarchy could 41 combine their sets of attributes for each log record, but there was no demand 42 in real world applications for such a feature. It can be added though, if 43 it proves useful. 44 </p> 45</div> 46<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 47<td align="left"></td> 48<td align="right"><div class="copyright-footer">Copyright © 2007-2019 Andrey Semashev<p> 49 Distributed under the Boost Software License, Version 1.0. (See accompanying 50 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>). 51 </p> 52</div></td> 53</tr></table> 54<hr> 55<div class="spirit-nav"> 56<a accesskey="p" href="why_not_lazy_streaming.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../rationale.html"><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="fork_support.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a> 57</div> 58</body> 59</html> 60
