On Wed, Apr 14, 2021 at 12:43 AM Ralph Goers <ralph.go...@dslextreme.com>
wrote:
> I started doing the work to modularize log4j-core last night. We have a
> blocker in that the disruptor has not had a release in 3 years. They
> committed the change to make it an automatic module over a year ago and
> since have fully modularized it. They simply haven’t performed a release.
>
> As I was going through the module descriptor (see below) it seems to me
> that we have far more dependencies in core than I would really like. For
> example, despite moving the Jackson Layouts to their own modules we still
> have a dependency on Jackson. We also have dependencies on things like
> java.rmi, java.naming, java.sql. I am also not clear on whether they are
> all really optional or not. Ideally, the only required dependency we should
> have is for java.base. For example, we need java.rmi because Log4jLogEvent
> uses MarshalledObject. I have no idea why we need that particular class to
> wrap a log event. Couldn’t we have created our own class for that?
My memory is a bit vague, but I think the reason for using a JDK class and
not a log4j class was to prevent memory leaks in thread pools shared across
web applications in servlet containers.
Perhaps I am confusing things here, but you may remember that if there is a
reference to a log4j class in a threadlocal, then that can prevent all
log4j classes from being garbage collected when the web app is restarted.
By serializing all data into a JDK class we avoid that problem. We could
also serialize into a byte array I guess, that would work just fine as
well. At the time I thought that MarshalledObject expressed the intent
better than a byte array, and it has some convenience methods for
serializing and deserializing. Other than that there is nothing special
about MarshalledObject itself.
> We need java.desktop because java.beans now lives there. Perhaps we could
> look at what those are and if it is really just one or two utility methods
> implement them locally.
>
> In the meantime I have created an issue with the Disruptor asking for a
> release. I can’t do much more with core until that is available. I can move
> on to other modules.
>
> We also need to look at the list of exports below and the classes in them
> and determine what is really public and what should be private.
>
>
> Thoughts?
>
> Ralph
>
>
> module org.apache.logging.log4j.core {
> exports org.apache.logging.log4j.core;
> exports org.apache.logging.log4j.core.appender;
> exports org.apache.logging.log4j.core.appender.db;
> exports org.apache.logging.log4j.core.appender.nosql;
> exports org.apache.logging.log4j.core.appender.rewrite;
> exports org.apache.logging.log4j.core.appender.rolling;
> exports org.apache.logging.log4j.core.appender.rolling.action;
> exports org.apache.logging.log4j.core.appender.routing;
> exports org.apache.logging.log4j.core.async;
> exports org.apache.logging.log4j.core.config;
> exports org.apache.logging.log4j.core.config.arbiters;
> exports org.apache.logging.log4j.core.config.builder.api;
> exports org.apache.logging.log4j.core.config.builder.impl;
> exports org.apache.logging.log4j.core.config.composite;
> exports org.apache.logging.log4j.core.config.json;
> exports org.apache.logging.log4j.core.config.plugins;
> exports org.apache.logging.log4j.core.config.plugins.convert;
> exports org.apache.logging.log4j.core.config.plugins.inject;
> exports org.apache.logging.log4j.core.config.plugins.util;
> exports org.apache.logging.log4j.core.config.plugins.visitors;
> exports org.apache.logging.log4j.core.config.properties;
> exports org.apache.logging.log4j.core.config.status;
> exports org.apache.logging.log4j.core.config.xml;
> exports org.apache.logging.log4j.core.config.yaml;
> exports org.apache.logging.log4j.core.filter;
> exports org.apache.logging.log4j.core.impl;
> exports org.apache.logging.log4j.core.jmx;
> exports org.apache.logging.log4j.core.layout;
> exports org.apache.logging.log4j.core.lookup;
> exports org.apache.logging.log4j.core.message;
> exports org.apache.logging.log4j.core.net;
> exports org.apache.logging.log4j.core.net.ssl;
> exports org.apache.logging.log4j.core.osgi;
> exports org.apache.logging.log4j.core.parser;
> exports org.apache.logging.log4j.core.pattern;
> exports org.apache.logging.log4j.core.script;
> exports org.apache.logging.log4j.core.selector;
> exports org.apache.logging.log4j.core.time;
> exports org.apache.logging.log4j.core.tools;
> exports org.apache.logging.log4j.core.tools.picocli;
> exports org.apache.logging.log4j.core.util;
> exports org.apache.logging.log4j.core.util.datetime;
>
> requires transitive java.desktop;
> requires transitive java.management;
> requires java.naming;
> requires transitive java.sql;
> requires java.rmi;
> requires transitive java.scripting;
> requires java.xml;
> requires org.apache.logging.log4j;
> requires org.apache.logging.log4j.plugins;
> //requires transitive com.lmax.distruptor;
> requires transitive org.osgi.core;
> requires transitive com.conversantmedia.disruptor;
> requires transitive com.fasterxml.jackson.core;
> requires transitive com.fasterxml.jackson.databind;
> requires transitive com.fasterxml.jackson.dataformat.xml;
> requires transitive com.fasterxml.jackson.dataformat.yaml;
> requires transitive org.apache.commons.compress;
> requires transitive org.fusesource.jansi;
> uses org.apache.logging.log4j.core.util.ContextDataProvider;
> provides
> org.apache.logging.log4j.message.ThreadDumpMessage$ThreadInfoFactory with
> org.apache.logging.log4j.core.message.ExtendedThreadInfoFactory;
> provides org.apache.logging.log4j.core.util.ContextDataProvider with
> org.apache.logging.log4j.core.impl.ThreadContextDataProvider;
> provides org.apache.logging.log4j.spi.Provider with
> org.apache.logging.log4j.core.impl.Log4jProvider;
> provides org.apache.logging.log4j.plugins.processor.PluginService with
> org.apache.logging.log4j.core.plugins.Log4jPlugins;
>
>
