Go to hazelcast.org/documentation

Logging Configuration

Hazelcast has a flexible logging configuration and does not depend on any logging framework except JDK logging. It has in-built adaptors for a number of logging frameworks and also supports custom loggers by providing logging interfaces.

To use built-in adaptors, you should set hazelcast.logging.type property to one of predefined types below.

  • jdk: JDK logging (default)

  • log4j: Log4j

  • slf4j: Slf4j

  • none: disable logging

You can set hazelcast.logging.type through XML configuration, API configuration or JVM system property.

  • XML Configuration
<hazelcast xsi:schemaLocation="http://www.hazelcast.com/schema/config
    http://www.hazelcast.com/schema/config/hazelcast-config-3.0.xsd"
    xmlns="http://www.hazelcast.com/schema/config"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">

    ....

    <properties>
        <property name="hazelcast.logging.type">jdk</property>
        ....
    </properties>
</hazelcast>
  • API Configuration
Config cfg = new Config() ;
cfg.setProperty("hazelcast.logging.type", "log4j");

  • System Property

    • Using JVM parameter: java -Dhazelcast.logging.type=slf4j
    • Using System class: System.setProperty("hazelcast.logging.type", "none");

To use custom logging feature you should implement com.hazelcast.logging.LoggerFactory and com.hazelcast.logging.ILogger interfaces and set system property hazelcast.logging.class as your custom LoggerFactory class name.

-Dhazelcast.logging.class=foo.bar.MyLoggingFactory

You can also listen to logging events generated by Hazelcast runtime by registering LogListeners to LoggingService.

LogListener listener = new LogListener() {
    public void log(LogEvent logEvent) {
        // do something
    }
}
LoggingService loggingService = Hazelcast.getLoggingService();
loggingService.addLogListener(Level.INFO, listener):

Through the LoggingService, you can get the current used ILogger implementation and log your own messages, too.