Index: lams_common/src/java/org/lamsfoundation/lams/tool/service/ILamsCoreToolService.java
===================================================================
diff -u -r622d79936d49e9d9e7011b2a493cfebbcee07d79 -r884b5578b8b6b8a5c269f87ac6c634abbe916455
--- lams_common/src/java/org/lamsfoundation/lams/tool/service/ILamsCoreToolService.java	(.../ILamsCoreToolService.java)	(revision 622d79936d49e9d9e7011b2a493cfebbcee07d79)
+++ lams_common/src/java/org/lamsfoundation/lams/tool/service/ILamsCoreToolService.java	(.../ILamsCoreToolService.java)	(revision 884b5578b8b6b8a5c269f87ac6c634abbe916455)
@@ -62,5 +62,14 @@
     
     public void updateToolSession(ToolSession toolSession);
 
-    public String getToolURLByMode(ToolActivity activity, User learner, ToolAccessMode accessMode);
+    /**
+     * Return tool activity url for a learner according to the access mode.
+     * For example, the monitor side sould passed in the teacher mode and 
+     * learning side sould pass in the learner mode.
+     * @param activity the requested activity.
+     * @param learner the current learner.
+     * @param accessMode tool access mode.
+     * @return the tool access url with tool session id and access mode.
+     */
+    public String getToolURLByMode(ToolActivity activity, User learner, ToolAccessMode accessMode) throws LamsToolServiceException;
 }
Index: lams_common/src/java/org/lamsfoundation/lams/tool/service/LamsCoreToolService.java
===================================================================
diff -u -r622d79936d49e9d9e7011b2a493cfebbcee07d79 -r884b5578b8b6b8a5c269f87ac6c634abbe916455
--- lams_common/src/java/org/lamsfoundation/lams/tool/service/LamsCoreToolService.java	(.../LamsCoreToolService.java)	(revision 622d79936d49e9d9e7011b2a493cfebbcee07d79)
+++ lams_common/src/java/org/lamsfoundation/lams/tool/service/LamsCoreToolService.java	(.../LamsCoreToolService.java)	(revision 884b5578b8b6b8a5c269f87ac6c634abbe916455)
@@ -32,6 +32,7 @@
 import org.lamsfoundation.lams.tool.ToolSessionManager;
 import org.lamsfoundation.lams.tool.dao.IToolSessionDAO;
 import org.lamsfoundation.lams.usermanagement.User;
+import org.lamsfoundation.lams.util.WebUtil;
 import org.springframework.beans.BeansException;
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.ApplicationContextAware;
@@ -175,12 +176,33 @@
     }
     
     /**
+     * @throws LamsToolServiceException
      * @see org.lamsfoundation.lams.tool.service.ILamsCoreToolService#getToolURLByMode(org.lamsfoundation.lams.learningdesign.ToolActivity, org.lamsfoundation.lams.usermanagement.User, org.lamsfoundation.lams.tool.ToolAccessMode)
      */
-    public String getToolURLByMode(ToolActivity activity, User learner, ToolAccessMode accessMode)
+    public String getToolURLByMode(ToolActivity activity, User learner, ToolAccessMode accessMode) throws LamsToolServiceException
     {
-        // TODO Auto-generated method stub
-        return null;
+        ToolSession toolSession = toolSessionDAO.getToolSessionByLearner(learner, activity);
+
+        if(accessMode==ToolAccessMode.LEARNER)
+            // Append toolSessionId to tool URL		
+            return activity.getTool().getLearnerUrl() + "&"
+                	+ WebUtil.PARAM_TOOL_SESSION_ID + "="
+                	+ toolSession.getToolSessionId().toString() + "&"
+                	+ WebUtil.PARAM_MODE + "=" + ToolAccessMode.LEARNER;
+        else if(accessMode == ToolAccessMode.TEACHER)
+            // Append toolSessionId to tool URL		
+            return activity.getTool().getLearnerUrl() + "&"
+                	+ WebUtil.PARAM_TOOL_SESSION_ID + "="
+                	+ toolSession.getToolSessionId().toString() + "&"
+                	+ WebUtil.PARAM_MODE + "=" + ToolAccessMode.TEACHER;
+        else if (accessMode == ToolAccessMode.AUTHOR)
+            // Append toolSessionId to tool URL		
+            return activity.getTool().getAuthorUrl() + "&"
+                	+ WebUtil.PARAM_TOOL_SESSION_ID + "="
+                	+ toolSession.getToolSessionId().toString() + "&"
+                	+ WebUtil.PARAM_MODE + "=" + ToolAccessMode.TEACHER;
+        
+        throw new LamsToolServiceException("Unknown tool access mode:"+accessMode.toString());
     }    
     //---------------------------------------------------------------------
     // Helper Methods
Index: lams_common/test/java/org/lamsfoundation/lams/tool/service/TestLamsToolService.java
===================================================================
diff -u -r0735f8bbbe378127d27795e3d9773f3c1293ed41 -r884b5578b8b6b8a5c269f87ac6c634abbe916455
--- lams_common/test/java/org/lamsfoundation/lams/tool/service/TestLamsToolService.java	(.../TestLamsToolService.java)	(revision 0735f8bbbe378127d27795e3d9773f3c1293ed41)
+++ lams_common/test/java/org/lamsfoundation/lams/tool/service/TestLamsToolService.java	(.../TestLamsToolService.java)	(revision 884b5578b8b6b8a5c269f87ac6c634abbe916455)
@@ -22,6 +22,8 @@
 
 package org.lamsfoundation.lams.tool.service;
 
+import org.apache.log4j.Logger;
+import org.lamsfoundation.lams.tool.ToolAccessMode;
 import org.lamsfoundation.lams.tool.ToolDataAccessTestCase;
 import org.lamsfoundation.lams.tool.ToolSession;
 import org.lamsfoundation.lams.tool.dao.hibernate.ToolSessionDAO;
@@ -36,6 +38,7 @@
  */
 public class TestLamsToolService extends ToolDataAccessTestCase
 {
+	private static Logger log = Logger.getLogger(TestLamsToolService.class);
     private ILamsCoreToolService toolService;
     
     /*
@@ -83,8 +86,30 @@
     {
         ToolSession tgroupedToolSession = toolService.getToolSessionByActivity(this.testUser,
                                                                                 this.testGroupedActivity);
-        
         assertNotNull(tgroupedToolSession);
-
     }
+    
+    public void testGetToolURLByLearnerMode() throws LamsToolServiceException
+    {
+        String learnerUrl = toolService.getToolURLByMode(testNonGroupedActivity,testUser,ToolAccessMode.LEARNER);
+        
+        assertNotNull(learnerUrl);
+        log.info("learner url:"+learnerUrl);
+    }
+    
+    public void testGetToolURLByTeacherMode() throws LamsToolServiceException
+    {
+        String monitorUrl = toolService.getToolURLByMode(testNonGroupedActivity,testUser,ToolAccessMode.TEACHER);
+        
+        assertNotNull(monitorUrl);
+        log.info("learner url:"+monitorUrl);
+    }
+    
+    public void testGetToolURLByAuthorMode() throws LamsToolServiceException
+    {
+        String authorUrl = toolService.getToolURLByMode(testNonGroupedActivity,testUser,ToolAccessMode.AUTHOR);
+        
+        assertNotNull(authorUrl);
+        log.info("learner url:"+authorUrl);
+    }
 }