RA-552:Adding the View Logged in Users functionality to core

web/src/main/java/org/openmrs/web/filter/util/CurrentUsers.java

@@ -0,0 +1,97 @@
+package org.openmrs.web.filter.util;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.Map;
+import java.util.TreeMap;
+
+import javax.servlet.ServletContext;
+import javax.servlet.http.HttpSession;
+
+import org.apache.commons.lang.StringUtils;
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.openmrs.User;
+import org.openmrs.web.WebConstants;
+
+public class CurrentUsers {
+
+	private static final Log log = LogFactory.getLog(CurrentUsers.class);
+
+	/**
+	 * Initialize the current users list.
+	 * 
+	 * @param servletContext
+	 */
+
+	public static Map<String,String> init(ServletContext servletContext){
+
+		Map<String,String> currentUserMap = Collections.synchronizedMap(new TreeMap<String,String>());
+		servletContext.setAttribute(WebConstants.CURRENT_USERS,currentUserMap);
+		return  currentUserMap;
+
+	}
+	/**
+	 * Get the current list of map of users stored in the session
+	 * 
+	 * @param httpSession the current session
+	 * @return map of users logged in
+	 */
+	 @SuppressWarnings("unchecked")
+	private static Map<String,String> getCurrentUsers(HttpSession httpSession){
+		Map<String,String> currentUsers = (Map<String,String>) httpSession.getServletContext().getAttribute(WebConstants.CURRENT_USERS);
+
+	    if(currentUsers == null) {
+		 currentUsers = init(httpSession.getServletContext());
+	    }
+
+	    return currentUsers;
+	 }
+
+	  /**
+		* Add the user to the current users.
+		* 
+		* @param httpSession
+	    * @param user the user that just logged in
+	  */
+	  public static void addUser(HttpSession httpSession,User user) {
+		  Map<String,String> currentUsers = getCurrentUsers(httpSession);
+
+		  String currentUserName = user.getUsername();
+		  //if the user name is blank then print their system id
+		  if(StringUtils.isBlank(currentUserName)) {
+			  currentUserName = "systemid:" + user.getSystemId();
+
+		  }
+
+		  if(log.isDebugEnabled()) {
+
+			  log.debug("Adding current user name" + currentUserName);
+
+		  }
+
+		  currentUsers.put(httpSession.getId(),currentUserName);
+
+	  }
+
+	  /**
+		* Get sorted user names list.
+		* 
+		* @param httpSession
+		* @return sorted user names
+		*/
+	  public static List<String> getCurrentUsernames(HttpSession httpSession){
+		  Map<String,String> currentUsers = getCurrentUsers(httpSession);
+		  List<String> userNames = new ArrayList<String>();
+		  synchronized(currentUsers) {
+			  for(String value:currentUsers.values()) {
+				  userNames.add(value);
+			  }
+			  Collections.sort(userNames);
+
+		  }
+		  return userNames;
+	  }
+
+}