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</o:shapelayout></xml><![endif]--></head><body lang=NL link="#0563C1" vlink=purple style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal>Hi,</p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span lang=EN-US>With both the answers from Alan and Rémi it is clear to me that the implementation of loading configuration in the simplelogger doesn’t fit my requirements.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>It is called “simple” for a reason.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>I prefer to depend on existing SLF4JProviders, but based on possible extra requirements it might be worth writing my own provider.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Thanks,<o:p></o:p></span></p><div><div><p class=MsoNormal><span lang=EN-US>Robert</span><span lang=EN-US style='font-size:12.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:NL'><o:p></o:p></span></p></div><div><p class=MsoNormal><span lang=EN-US style='font-size:12.0pt;font-family:"Arial",sans-serif;color:black'><o:p> </o:p></span></p></div><div class=MsoNormal align=center style='text-align:center'><span style='font-size:12.0pt;font-family:"Arial",sans-serif;color:black'><hr size=2 width="100%" align=center id=zwchr></span></div><div><blockquote style='border:none;border-left:solid #1010FF 1.5pt;padding:0cm 0cm 0cm 4.0pt;margin-left:3.75pt;margin-top:5.0pt;margin-bottom:5.0pt'><p class=MsoNormal><b><span style='font-size:12.0pt;font-family:"Helvetica",sans-serif;color:black'>From: </span></b><span style='font-size:12.0pt;font-family:"Helvetica",sans-serif;color:black'>"Robert Scholte" <<a href="mailto:rfscholte@apache.org">rfscholte@apache.org</a>><br><b>To: </b>"jigsaw-dev" <<a href="mailto:jigsaw-dev@openjdk.org">jigsaw-dev@openjdk.org</a>><br><b>Sent: </b>Friday, January 26, 2024 11:46:51 AM<br><b>Subject: </b>Custom Classloaders<o:p></o:p></span></p></blockquote></div><div><blockquote style='border:none;border-left:solid #1010FF 1.5pt;padding:0cm 0cm 0cm 4.0pt;margin-left:3.75pt;margin-top:5.0pt;margin-bottom:5.0pt'><p class=MsoNormal><span style='color:black'>Hi,<o:p></o:p></span></p></blockquote><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:NL'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:NL'>Hello Robert,<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:NL'>you were miss at last Devoxx.be,<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:NL'><o:p> </o:p></span></p></div><blockquote style='border:none;border-left:solid #1010FF 1.5pt;padding:0cm 0cm 0cm 4.0pt;margin-left:3.75pt;margin-top:5.0pt;margin-bottom:5.0pt'><p class=MsoNormal><span style='color:black'> <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:black'>I’m working on a new application, using jlink to build it.</span><span style='color:black'><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:black'>One challenge is related to the simplelogger of SLF4J (as SLF4J-api is probably the most used logging api, the simplelogger implementation matches my requirements)</span><span style='color:black'><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:black'>There are 2 things that I would like to adjust:</span><span style='color:black'><o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:18.0pt;text-indent:-18.0pt;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='color:black'><span style='mso-list:Ignore'>1.<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN-US style='color:black'>Simplelogger uses the classloader to find the simplelogger.properties ( <a href="https://github.com/qos-ch/slf4j/blob/master/slf4j-simple/src/main/java/org/slf4j/simple/SimpleLoggerConfiguration.java#L107-L130" target="_blank">https://github.com/qos-ch/slf4j/blob/master/slf4j-simple/src/main/java/org/slf4j/simple/SimpleLoggerConfiguration.java#L107-L130</a> ). </span><span style='color:black'><o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:18.0pt'><span lang=EN-US style='color:black'>However, I want to externalize this file to ${java.home}/conf/simplelogger.properties, so users can adjust it to their preferences. If I could change the classloader I could control where to find this file.</span><span style='color:black'><o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:18.0pt'><span lang=EN-US style='color:black'>When bundling simplelogger with jlink the jar will end up in the AppClassloader due to the SimpleServiceProvider. </span><span style='color:black'><o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:18.0pt'><span lang=EN-US style='color:black'>The only option to avoid this, is to move this jar to a separate directory and when making a new ModuleLayer, and use ModuleFinder with this path. </span><span style='color:black'><o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:18.0pt'><span lang=EN-US style='color:black'>But still, I see no way to change the classloader for this jar.</span><span style='color:black'><o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:18.0pt;text-indent:-18.0pt;mso-list:l1 level1 lfo2'><![if !supportLists]><span style='color:black'><span style='mso-list:Ignore'>2.<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span lang=EN-US style='color:black'>The simplelogger.properties is the default configuration, and I want to make it possible to override these values. </span><span style='color:black'><o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:18.0pt'><span lang=EN-US style='color:black'>The simplelogger offers the option to use SystemProperties to override values from simplelogger.properties.</span><span style='color:black'><o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:18.0pt'><span lang=EN-US style='color:black'>I want to avoid that the System.properties will be polluted with entities just for logging.</span><span style='color:black'><o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:18.0pt'><span lang=EN-US style='color:black'>As far as I know it is not possible to scope System.properties: they are global, available for every part of the application.</span><span style='color:black'><o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:18.0pt'><span lang=EN-US style='color:black'>Another idea I had was to extend the simplelogging.properties resources at runtime using the SequenceInputStream, and for this I also need to have control over the classloader, as it requires to override the ClassLoader.getResourceAsStream()</span><span style='color:black'><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:black'>It seems both challenges could be solved if could control the classloader (while still being protected by jdk.internal.loader.Loader).</span><span style='color:black'><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:black'>Am I missing some feature or it there another way to solve these issues?</span><span style='color:black'><o:p></o:p></span></p></blockquote><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:NL'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:NL'>yes, <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:NL'>as you said yourself, you box yourself in a corner by wanting to use Simplelogger which does not provide a great deal of ways to configure it.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:NL'>I'm sure they are other loggers that, while heavier, are more capable in term of configuration.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:NL'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:NL'>You are cursed by your own knowledge in this case, as an application developer, you should pretend that ClassLoaders do not exist, like the rest of the application developers do.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:NL'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:NL'>Let me try a trick, those are not the classloaders you are looking for :)<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:NL'><o:p> </o:p></span></p></div><blockquote style='border:none;border-left:solid #1010FF 1.5pt;padding:0cm 0cm 0cm 4.0pt;margin-left:3.75pt;margin-top:5.0pt;margin-bottom:5.0pt'><p class=MsoNormal><span lang=EN-US style='color:black'>Best,</span><span style='color:black'><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:black'>Robert </span><span style='color:black'><o:p></o:p></span></p></blockquote><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:NL'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:NL'>regards,<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:NL'>Rémi<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:NL'><o:p> </o:p></span></p></div></div></div></div></body></html>