Log4j

# Set root logger level to DEBUG and its only appender to A1.
log4j.rootLogger=DEBUG, A1, A2

# A1 is set to be a ConsoleAppender
# Using a Patternlayout + Given Pattern below
log4j.appender.A1=org.apache.log4j.ConsoleAppender
log4j.appender.A1.layout=org.apache.log4j.PatternLayout
log4j.appender.A1.layout.ConversionPattern=%-4r [%t] %-5p %c %x - %m%n

# A2 is set to be a NoSQLAppender
# Specifically MongoDB, writing to our DB directly
log4j.appender.A2=org.apache.log4j.appender.nosql.NoSqlAppender
A2.name=MongoDB
A2.ignoreExceptions=true
A2.NoSqlProvider=org.apache.log4j.mongodb.MongoDbProvider
A2.server=localhost
A2.protocol=http
A2.port=27017
A2.databaseName=appLog
A2.collectionName=logtest

Patterns:

Placeholder	Represents	Example
%d	Timestamp	%d → 2018-05-15 11:50:15,699
%c	Class Name	%c → MyClassWithLogger
%t	Thread Name	[%t] → [main]
%m	Message	%m → My super important log message
%n	A Line Break	%n → \n

Here are a few complete patter examples ready to use:

# Pattern:
%-4r [%t] %-5p %c - %m%n

# Output:
859  [main] INFO  Broker [] - New Listener is added to Broker.

---
# Pattern:
%d %-5p [%t] %C{2} (%F:%L) - %m%n

# Output:
2018-05-15 11:50:15,699 INFO  [main] Broker (Broker.java:23) - New Listener is added to Broker.

---

# Pattern:
%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n
17:13:01.540 [main] ERROR MyApp - Didn't do it.