Remove unused import in JUL Java agent

[lttng-ust.git] / liblttng-ust-java-agent / java / lttng-ust-agent-jul / org / lttng / ust / agent / jul / LttngJulAgent.java

diff --git a/liblttng-ust-java-agent/java/lttng-ust-agent-jul/org/lttng/ust/agent/jul/LttngJulAgent.java b/liblttng-ust-java-agent/java/lttng-ust-agent-jul/org/lttng/ust/agent/jul/LttngJulAgent.java
index fa92f64541b04788af12015bc3fa8d30343466d9..a2581f6bc1c24ad6d40797f654bc20f266a619fa 100644 (file)
--- a/liblttng-ust-java-agent/java/lttng-ust-agent-jul/org/lttng/ust/agent/jul/LttngJulAgent.java
+++ b/liblttng-ust-java-agent/java/lttng-ust-agent-jul/org/lttng/ust/agent/jul/LttngJulAgent.java
@@ -17,6 +17,15 @@
 
 package org.lttng.ust.agent.jul;
 
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
+import java.util.Set;
+import java.util.TreeSet;
+import java.util.logging.Handler;
+import java.util.logging.LogManager;
+import java.util.logging.Logger;
+
 import org.lttng.ust.agent.AbstractLttngAgent;
 
 /**
@@ -39,4 +48,54 @@ class LttngJulAgent extends AbstractLttngAgent<LttngLogHandler> {
                return instance;
        }
 
+       @Override
+       public Collection<String> listAvailableEvents() {
+               Set<String> ret = new TreeSet<String>();
+
+               List<String> loggersNames = Collections.list(LogManager.getLogManager().getLoggerNames());
+               for (String name : loggersNames) {
+                       /*
+                        * Skip the root logger. An empty string is not a valid event name
+                        * in LTTng.
+                        */
+                       if (name.equals("") || name.equals("global")) {
+                               continue;
+                       }
+
+                       /*
+                        * Check if that logger has at least one LTTng JUL handler attached.
+                        */
+                       Logger logger = Logger.getLogger(name);
+                       if (hasLttngHandlerAttached(logger)) {
+                               ret.add(name);
+                       }
+               }
+
+               return ret;
+       }
+
+       private static boolean hasLttngHandlerAttached(Logger logger) {
+               for (Handler handler : logger.getHandlers()) {
+                       if (handler instanceof LttngLogHandler) {
+                               return true;
+                       }
+               }
+
+               /*
+                * A parent logger, if any, may be connected to an LTTng handler. In
+                * this case, we will want to include this child logger in the output,
+                * since it will be accessible by LTTng.
+                */
+               Logger parent = logger.getParent();
+               if (parent != null) {
+                       return hasLttngHandlerAttached(parent);
+               }
+
+               /*
+                * We have reached the root logger and have not found any LTTng handler,
+                * this event will not be accessible.
+                */
+               return false;
+       }
+
 }