I am trying to produce a proof of concept shipping logging from Log4J through JMS using the log4J JMSAppender. I have tried ActiveMQ and the example supplied with it. I have torn this example apart, and made it more generic and compatible with multiple platforms.
It looks like I have it all plumbed up OK as I can see a connection to the ActiveMQ happening, but the code hangs when I get the InitialContext ( with -Dlog4j.debug set the ActiveMQ client classes seem to invoke log4J and load the properties which in turn try to make a connection to the JMS for the JMSAppender) and then the code just hangs. I have tried to isolate the log messages heading to the JMS by only defining the appender for a single named logger, and the org.apache.activemq package is configured to use the ConsoleAppender
The same code works just fine when pointed to a Weblogic Server with a JMS queue configured up but for maximum compatibility I need to try to make it work with ActiveMQ
Is there some 'magic' bit of configuration that I am missing to make ActiveMQ work correctly?
-- some sample bits from the work so far to flesh this question out a bit now I have the code to hand
log4j-jms.properties
log4j.rootLogger=INFO, stdout
## Be sure that ActiveMQ messages are not logged to 'jms' appender
log4j.logger.org.apache=ERROR, stdout
log4j.logger.javax=ERROR,stdout
log4j.logger.java=ERROR,stdout
log4j.logger.demo=DEBUG,jms
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d %-5p %c - %m%n
## Configure 'jms' appender. You'll also need jndi.properties file in order to make it work
log4j.appender.jms=org.apache.log4j.net.JMSAppender
log4j.appender.jms.InitialContextFactoryName=org.apache.activemq.jndi.ActiveMQInitialContextFactory
log4j.appender.jms.ProviderURL=tcp://localhost:61616
log4j.appender.jms.TopicBindingName=topic.logTopic
log4j.appender.jms.TopicConnectionFactoryBindingName=ConnectionFactory
The object of this was to create a named appender 'demo' and in the sample code grab that to log to make sure that activemq logging was not trying to send itself to JMS
code example. Its a bit of a mess as I have been hacking around with it to try to make things work. As it stands it will work when I point it to Weblogic, and switch the log4j config similarly. The object in this code was to make sure I had the listener for the topic running in a separate thread
NewLog4jJMSAppenderExample.java
import javax.jms.*; import javax.naming.Context; import javax.naming.InitialContext; import javax.naming.NamingException; import org.apache.log4j.Logger; import org.apache.log4j.spi.LoggingEvent;
import java.util.Properties;
/**
* A simple example of log4j jms appender in conjuction with ActiveMQ
*/
public class NewLog4jJMSAppenderExample {
Runnable listener;
Thread runner;
private enum MQImplementation {
ActiveMQ, Weblogic
};
public NewLog4jJMSAppenderExample() {
// create a logTopic topic consumer
listener = new BigEars();
System.out.println("******* Listener Created **********");
runner = new Thread(listener);
runner.start();
try {
Thread.sleep(10);
} catch (InterruptedException e) {
e.printStackTrace(); //To change body of catch statement use File | Settings | File Templates.
}
}
public static void main(String[] args) throws Exception {
System.out.println("******* I HAVE STARTED **********");
new NewLog4jJMSAppenderExample();
System.out.println("******* LOGGING **********");
// log a message
Logger log = Logger.getLogger("demo");
log.error("Test log");
Thread.sleep(100000);
System.exit(1);
}
public class BigEars implements Runnable, MessageListener {
ConnectionFactory factory;
Connection conn;
Session sess;
MessageConsumer consumer;
public BigEars() {
MQImplementation inUse = MQImplementation.ActiveMQ;
System.out.println("Constructing Bigears");
try {
Properties env = new Properties();
switch (inUse) {
case Weblogic:
env.put(Context.INITIAL_CONTEXT_FACTORY,
"weblogic.jndi.WLInitialContextFactory");
env.put(Context.PROVIDER_URL,
"t3://localhost:7001");
break;
case ActiveMQ:
env.put(Context.INITIAL_CONTEXT_FACTORY,
"org.apache.activemq.jndi.ActiveMQInitialContextFactory");
env.put(Context.PROVIDER_URL,
"tcp://localhost:61616");
break;
}
System.out.println("Initial Context");
InitialContext jndi = new InitialContext(env);
System.out.println("Factory");
factory = (TopicConnectionFactory) jndi.lookup("ConnectionFactory");
Topic theTopic = (Topic) jndi.lookup("topic.logTopic");
System.out.println("Connection");
conn = factory.createConnection();
System.out.println("******* I HAVE set up and created connection **********");
System.out.println("session");
sess = conn.createSession(false, Session.AUTO_ACKNOWLEDGE);
System.out.println("consumer");
consumer = sess.createConsumer(theTopic);
System.out.println("listener");
consumer.setMessageListener(this);
conn.start();
} catch (JMSException jme) {
System.out.println(jme);
} catch (NamingException ne) {
System.out.println(ne);
}
}
public void run() {
try {
System.out.println("******* zzzzzzzz! **********");
Thread.sleep(100000);
} catch (Exception e) {
e.printStackTrace(); //To change body of catch statement use File | Settings | File Templates.
}
}
public void onMessage(Message message) {
try {
try {
System.out.println("******* I GOT A MESSAGE **********");
// receive log event in your consumer
System.out.println(message.toString());
LoggingEvent event = (LoggingEvent) (((ObjectMessage) message).getObject());
System.out.println("Received log [" + event.getLevel() + "]: " + event.getMessage());
} catch (Exception e) {
e.printStackTrace();
}
} finally {
try {
consumer.close();
sess.close();
conn.close();
} catch (JMSException jme) {
System.out.println(jme);
}
}
}
} }
logging presented when -Dlog4j.debug set
******* I HAVE STARTED **********
Constructing Bigears
Initial Context
log4j: Trying to find [log4j-jms.properties] using context classloader sun.misc.Launcher$AppClassLoader@2c2bbd86.
log4j: Using URL [file:/Users/kevin/Desktop/apache-activemq-5.3.0/example/target/classes/log4j-jms.properties] for automatic log4j configuration.
log4j: Reading configuration from URL file:/Users/kevin/Desktop/apache-activemq-5.3.0/example/target/classes/log4j-jms.properties
log4j: Parsing for [root] with value=[INFO, stdout].
log4j: Level token is [INFO].
log4j: Category root set to INFO
log4j: Parsing appender named "stdout".
log4j: Parsing layout options for "stdout".
log4j: Setting property [conversionPattern] to [%d %-5p %c - %m%n].
log4j: End of parsing for "stdout".
log4j: Parsed "stdout" options.
log4j: Parsing for [org.apache] with value=[ERROR, stdout].
log4j: Level token is [ERROR].
log4j: Category org.apache set to ERROR
log4j: Parsing appender named "stdout".
log4j: Appender "stdout" was already parsed.
log4j: Handling log4j.additivity.org.apache=[null]
log4j: Parsing for [demo] with value=[DEBUG,jms].
log4j: Level token is [DEBUG].
log4j: Category demo set to DEBUG
log4j: Parsing appender named "jms".
log4j: Setting property [initialContextFactoryName] to [org.apache.activemq.jndi.ActiveMQInitialContextFactory].
log4j: Setting property [topicBindingName] to [topic.logTopic].
log4j: Setting property [topicConnectionFactoryBindingName] to [ConnectionFactory].
log4j: Setting property [providerURL] to [tcp://localhost:61616].
log4j: Getting initial context.
log4j: Looking up [ConnectionFactory]
log4j: About to create TopicConnection.
log4j: Creating TopicSession, non-transactional, in AUTO_ACKNOWLEDGE mode.
Here it just hangs and eventually times out