BAEL-5124 - Adding a module with examples of printing thread info in the log file using log4j (#11704)

* adding a example module for printing thread info in log file using log4j

* - fix: removing submodule

* - fix: Adding submodule

* - fix: Removing `.gitignore`, `README.md`, and `application.properties`.
- fix: Removing Spring boot and adding log4j2 from Maven Central

* - fix: Changing module name as suggested to log4j2-thread-info.
- fix: Fixing log path in log4j2 configuration

* - feat: Removing log4j2-thread-info module
- feat: Adding example code into existing log4j2 module

* - fix: Removing unnecessary logging

* - fix: Separating thread info in the logging pattern

* - fix: package name to lowercase

* lowercasing package name and variable name

* changing package name in configuration

* - fix: formatting

* - fix: formatting imports

logging-modules/log4j2/src/main/java/com/baeldung/logging/log4j2threadinfo/Log4j2ThreadInfo.java

@@ -0,0 +1,18 @@
+package com.baeldung.logging.log4j2threadinfo;
+
+import java.util.stream.IntStream;
+
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+
+public class Log4j2ThreadInfo {
+    private static final Logger logger = LogManager.getLogger(Log4j2ThreadInfo.class);
+
+    public static void main(String[] args) {
+        IntStream.range(0, 5).forEach(i -> {
+            Runnable runnable = () -> logger.info("Logging info");
+            Thread thread = new Thread(runnable);
+            thread.start();
+        });
+    }
+}

logging-modules/log4j2/src/main/resources/log4j2.xml

@@ -0,0 +1,30 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Configuration>
+    <Properties>
+        <Property name="LOG_PATTERN">
+            %d{yyyy-MM-dd HH:mm:ss.SSS} --- thread_id="%tid" thread_name="%tn" thread_priority="%tp" --- [%p] %m%n
+        </Property>
+    </Properties>
+    <Appenders>
+        <RollingFile name="RollingName" filename="logs/app.log"
+                     filePattern="$${date:yyyy-MM}/app-%d{MM-dd-yyyy}-%i.log">
+            <PatternLayout>
+                <Pattern>${LOG_PATTERN}</Pattern>
+            </PatternLayout>
+            <Policies>
+                <SizeBasedTriggeringPolicy size="20MB"/>
+            </Policies>
+        </RollingFile>
+        <Console name="Console" target="SYSTEM_OUT">
+            <PatternLayout pattern="${LOG_PATTERN}"/>
+        </Console>
+    </Appenders>
+    <Loggers>
+        <Logger name="com.baeldung.logging.log4j2threadinfo" level="trace">
+            <AppenderRef ref="Console"/>
+        </Logger>
+        <Root level="error">
+            <AppenderRef ref="RollingName"/>
+        </Root>
+    </Loggers>
+</Configuration>