# Logging
Logging is a very common feature for all applications. ES4X does not implement a logger, instead it just uses the logger
from the JDK, also known as java util logging or JUL. Even the console
object is linked to it, so you can disable
console from logging at a specific level at runtime just by using configuration.
In order to customize the logging, create a file logging.properties
with the configuration as you like. The default
configuration is:
handlers=java.util.logging.ConsoleHandler
java.util.logging.ConsoleHandler.formatter=io.reactiverse.es4x.jul.ANSIFormatter
java.util.logging.ConsoleHandler.level=FINEST
.level=INFO
io.reactiverse.level=INFO
io.vertx.level=INFO
com.hazelcast.level=INFO
io.netty.util.internal.PlatformDependent.level=SEVERE
You can see that there is a custom formatter, this is to offer you a ANSI
color logger. If the formatter is disabled all
logs will be in plain text without ANSI
codes.
TIP
To only log warning and errors at runtime, including from the console
object, just level up the level on the console
handler.
You can even ship the logs to other locations by adding more handlers.