[OLINGO-266] log&trace

lib/server-core/pom.xml

@@ -66,10 +66,15 @@
       <groupId>com.fasterxml.jackson.core</groupId>
       <artifactId>jackson-core</artifactId>
     </dependency>
+    <dependency>
+      <groupId>commons-logging</groupId>
+      <artifactId>commons-logging</artifactId>
+      <scope>test</scope>
+    </dependency>
     <dependency>
       <groupId>org.slf4j</groupId>
-      <artifactId>slf4j-log4j12</artifactId>
-      <version>1.7.6</version>
+      <artifactId>slf4j-simple</artifactId>
+      <scope>test</scope>
     </dependency>
   </dependencies>
 

lib/server-core/src/test/resources/simplelogger.properties

@@ -0,0 +1,20 @@
+#
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+#
+org.slf4j.simpleLogger.defaultLogLevel=debug
+org.slf4j.simpleLogger.logFile=System.out

lib/server-ref/pom.xml

@@ -54,6 +54,17 @@
       <scope>runtime</scope>
     </dependency>
  
+    <dependency>
+      <groupId>commons-logging</groupId>
+      <artifactId>commons-logging</artifactId>
+      <scope>runtime</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.slf4j</groupId>
+      <artifactId>slf4j-simple</artifactId>
+      <scope>runtime</scope>
+    </dependency>
+ 
     <dependency>
       <groupId>junit</groupId>
       <artifactId>junit</artifactId>

lib/server-ref/src/main/java/org/apache/olingo/server/ref/ReferenceServlet.java

@@ -28,13 +28,19 @@ import javax.servlet.http.HttpServletResponse;
 import org.apache.olingo.server.api.ODataHandler;
 import org.apache.olingo.server.api.ODataServer;
 import org.apache.olingo.server.ref.provider.EdmTechProvider;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 public class ReferenceServlet extends HttpServlet {
 
   private static final long serialVersionUID = 1L;
 
+  private static final Logger LOG = LoggerFactory.getLogger(ReferenceServlet.class);
+  
   @Override
   protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
+    LOG.debug("ReferenceServlet:service() called");
+    
     
     ODataHandler handler = ODataServer.newInstance().getHandler(new EdmTechProvider());