[FELIX-4942] Improve Logger to provide isDebugEnabled() and debug() methods

git-svn-id: https://svn.apache.org/repos/asf/felix/trunk@1690700 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/resolver/src/main/java/org/apache/felix/resolver/Logger.java b/resolver/src/main/java/org/apache/felix/resolver/Logger.java
index fd3a8a7..dbcaee9 100644
--- a/resolver/src/main/java/org/apache/felix/resolver/Logger.java
+++ b/resolver/src/main/java/org/apache/felix/resolver/Logger.java
@@ -75,14 +75,23 @@
         _log(level, msg, throwable);
     }
 
+    public boolean isDebugEnabled()
+    {
+        return m_logLevel >= LOG_DEBUG;
+    }
+
+    public final void debug(String msg)
+    {
+        _log(LOG_DEBUG, msg, null);
+    }
+
     protected void doLog(int level, String msg, Throwable throwable)
     {
         if (level > m_logLevel)
         {
             return;
         }
-        String s = "";
-        s = s + msg;
+        String s = msg;
         if (throwable != null)
         {
             s = s + " (" + throwable + ")";