X-Git-Url: http://git.lttng.org./?a=blobdiff_plain;f=doc%2Fexamples%2Fjava-jul%2FHello.java;h=cb9f24b198fc7be376b9a2d91f541e9e9b4e0e4e;hb=a60af3a5ee5d990c867ef190acfa81c180301ea2;hp=7016cf4956bc90736d3eeeafc2a817bfa281b879;hpb=d60dfbe48a0ceff16852f46419bcbc405502c61d;p=lttng-ust.git
diff --git a/doc/examples/java-jul/Hello.java b/doc/examples/java-jul/Hello.java
index 7016cf49..cb9f24b1 100644
--- a/doc/examples/java-jul/Hello.java
+++ b/doc/examples/java-jul/Hello.java
@@ -43,6 +43,21 @@ import org.lttng.ust.agent.jul.LttngLogHandler;
* the Logger, those will continue logging events normally.
*
*
+ *
+ * To obtain LTTng trace events, you should run the following sequence of
+ * commands:
+ *
+ *
+ *
+ * - $ lttng create
+ * - $ lttng enable-event -j -a
+ * - $ lttng start
+ * - (run this program)
+ * - $ lttng stop
+ * - $ lttng view
+ * - $ lttng destroy
+ *
+ *
* @author Alexandre Montplaisir
* @author David Goulet
*/
@@ -57,65 +72,23 @@ public class Hello {
* @param args
* Command-line arguments
* @throws IOException
- * @throws InterruptedException
+ * If the required native libraries cannot be found. You may
+ * have to specify "-Djava.library.path=..." on the "java"
+ * command line.
*/
- public static void main(String args[]) throws IOException, InterruptedException {
+ public static void main(String args[]) throws IOException {
/* Instantiate a LTTngLogHandler object, and attach it to our logger */
Handler lttngHandler = new LttngLogHandler();
LOGGER.addHandler(lttngHandler);
- /*
- * Gives you time to do some lttng commands before any event is hit.
- */
- Thread.sleep(5000);
-
- /* Trigger a tracing event using the JUL Logger created before. */
+ /* Log events using the JUL Logger created before. */
LOGGER.info("Hello World, the answer is " + 42);
+ LOGGER.info("Another info event");
+ LOGGER.severe("A severe event");
- /*
- * From this point on, the above message will be collected in the trace
- * if the event "Hello" is enabled for the JUL domain using the lttng
- * command line or the lttng-ctl API. For instance:
- *
- * $ lttng enable-event -j Hello
- */
-
- /*
- * A new logger is created here and fired after. Typically with JUL, you
- * use one static Logger per class. This example here can represent a
- * class being lazy-loaded later in the execution of the application.
- *
- * The agent has an internal timer that is fired every 5 seconds in
- * order to enable events that were not found at first but might need to
- * be enabled when a new Logger appears. Unfortunately, there is no way
- * right now to get notified of that so we have to actively poll.
- *
- * Using the --all command for instance, it will make this Logger
- * available in a LTTng trace after the internal agent's timer is fired.
- * (lttng enable-event -j -a).
- */
- Logger helloLogDelayed = Logger.getLogger("hello_delay");
-
- /*
- * Attach a handler to this new logger.
- *
- * Using the same handler as before would also work.
- */
- Handler lttngHandler2 = new LttngLogHandler();
- helloLogDelayed.addHandler(lttngHandler2);
-
- System.out.println("Firing hello delay in 10 seconds...");
- Thread.sleep(10000);
- helloLogDelayed.info("Hello World delayed...");
-
- System.out.println("Cleaning Hello");
-
- /*
- * Do not forget to close() all handlers so that the agent can shutdown
- * and the session daemon socket gets cleaned up explicitly.
- */
+ /* Cleanup */
+ LOGGER.removeHandler(lttngHandler);
lttngHandler.close();
- lttngHandler2.close();
}
}