Use classes instead of constants everywhere

17 files changed, 137 insertions, 114 deletions

diff --git a/src/org/traccar/Context.java b/src/org/traccar/Context.java
index 57c6bc908..a4fc5b679 100644
--- a/src/org/traccar/Context.java
+++ b/src/org/traccar/Context.java
@@ -59,14 +59,6 @@ import org.traccar.web.WebServer;
 
 public final class Context {
 
-    public static final String TYPE_USER = "User";
-    public static final String TYPE_DEVICE = "Device";
-    public static final String TYPE_GROUP = "Group";
-    public static final String TYPE_GEOFENCE = "Geofence";
-    public static final String TYPE_CALENDAR = "Calendar";
-    public static final String TYPE_ATTRIBUTE = "Attribute";
-    public static final String TYPE_DRIVER = "Driver";
-
     private Context() {
     }
 
diff --git a/src/org/traccar/api/BaseResource.java b/src/org/traccar/api/BaseResource.java
index 4ad1477c2..920bb3931 100644
--- a/src/org/traccar/api/BaseResource.java
+++ b/src/org/traccar/api/BaseResource.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 - 2016 Anton Tananaev (anton@traccar.org)
+ * Copyright 2015 - 2017 Anton Tananaev (anton@traccar.org)
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,13 +17,15 @@ package org.traccar.api;
 
 import java.sql.SQLException;
 import java.util.Iterator;
-import java.util.Map;
+import java.util.LinkedHashMap;
 
 import javax.ws.rs.core.SecurityContext;
 
 import org.traccar.Context;
 import org.traccar.database.DataManager;
 import org.traccar.model.BaseModel;
+import org.traccar.model.Device;
+import org.traccar.model.User;
 
 public class BaseResource {
 
@@ -38,34 +40,33 @@ public class BaseResource {
         return 0;
     }
 
-    protected void handlePermission(Map<String, Long> entity, boolean link) throws SQLException {
-        if (entity.size() != 2) {
-            throw new IllegalArgumentException();
-        }
+    protected void checkAndLinkPermission(LinkedHashMap<String, Long> entity, boolean link)
+            throws SQLException, ClassNotFoundException {
         Iterator<String> iterator = entity.keySet().iterator();
         String owner = iterator.next();
+        Class<?> ownerClass = DataManager.getClassByName(owner);
         String property = iterator.next();
+        Class<?> propertyClass = DataManager.getClassByName(property);
 
         long ownerId = entity.get(owner);
         long propertyId = entity.get(property);
 
-        if (!link && DataManager.makeName(owner).equals(Context.TYPE_USER)
-                && DataManager.makeName(property).equals(Context.TYPE_DEVICE)) {
+        if (!link && ownerClass.equals(User.class)
+                && propertyClass.equals(Device.class)) {
             if (getUserId() != ownerId) {
                 Context.getPermissionsManager().checkUser(getUserId(), ownerId);
             } else {
                 Context.getPermissionsManager().checkAdmin(getUserId());
             }
         } else {
-            Context.getPermissionsManager().checkPermission(owner, getUserId(), ownerId);
+            Context.getPermissionsManager().checkPermission(ownerClass, getUserId(), ownerId);
         }
-        Context.getPermissionsManager().checkPermission(property, getUserId(), propertyId);
+        Context.getPermissionsManager().checkPermission(propertyClass, getUserId(), propertyId);
 
-        Context.getDataManager().linkObject(owner, ownerId, property, propertyId, link);
+        Context.getDataManager().linkObject(ownerClass, ownerId, propertyClass, propertyId, link);
     }
 
-    protected void linkNew(BaseModel entity) throws SQLException {
-        Context.getDataManager().linkObject("userId", getUserId(),
-                entity.getClass().getSimpleName(), entity.getId(), true);
+    protected void linkNewEntity(BaseModel entity) throws SQLException {
+        Context.getDataManager().linkObject(User.class, getUserId(), entity.getClass(), entity.getId(), true);
     }
 }
diff --git a/src/org/traccar/api/resource/AttributeResource.java b/src/org/traccar/api/resource/AttributeResource.java
index 63cdfb2a7..7e6947d26 100644
--- a/src/org/traccar/api/resource/AttributeResource.java
+++ b/src/org/traccar/api/resource/AttributeResource.java
@@ -87,7 +87,7 @@ public class AttributeResource extends BaseResource {
     private Response add(Attribute entity) throws SQLException {
         Context.getPermissionsManager().checkReadonly(getUserId());
         Context.getAttributesManager().addItem(entity);
-        linkNew(entity);
+        linkNewEntity(entity);
         Context.getAttributesManager().refreshUserItems();
         return Response.ok(entity).build();
     }
@@ -128,7 +128,7 @@ public class AttributeResource extends BaseResource {
     @PUT
     public Response update(Attribute entity) throws SQLException {
         Context.getPermissionsManager().checkReadonly(getUserId());
-        Context.getPermissionsManager().checkPermission(Context.TYPE_ATTRIBUTE, getUserId(), entity.getId());
+        Context.getPermissionsManager().checkPermission(Attribute.class, getUserId(), entity.getId());
         Context.getAttributesManager().updateItem(entity);
         return Response.ok(entity).build();
     }
@@ -137,7 +137,7 @@ public class AttributeResource extends BaseResource {
     @DELETE
     public Response remove(@PathParam("id") long id) throws SQLException {
         Context.getPermissionsManager().checkReadonly(getUserId());
-        Context.getPermissionsManager().checkPermission(Context.TYPE_ATTRIBUTE, getUserId(), id);
+        Context.getPermissionsManager().checkPermission(Attribute.class, getUserId(), id);
         Context.getAttributesManager().removeItem(id);
         return Response.noContent().build();
     }
diff --git a/src/org/traccar/api/resource/CalendarResource.java b/src/org/traccar/api/resource/CalendarResource.java
index d29080ee2..30f5df6b8 100644
--- a/src/org/traccar/api/resource/CalendarResource.java
+++ b/src/org/traccar/api/resource/CalendarResource.java
@@ -66,7 +66,7 @@ public class CalendarResource extends BaseResource {
     public Response add(Calendar entity) throws SQLException {
         Context.getPermissionsManager().checkReadonly(getUserId());
         Context.getCalendarManager().addItem(entity);
-        linkNew(entity);
+        linkNewEntity(entity);
         Context.getCalendarManager().refreshUserItems();
         return Response.ok(entity).build();
     }
@@ -75,7 +75,7 @@ public class CalendarResource extends BaseResource {
     @PUT
     public Response update(Calendar entity) throws SQLException {
         Context.getPermissionsManager().checkReadonly(getUserId());
-        Context.getPermissionsManager().checkPermission(Context.TYPE_CALENDAR, getUserId(), entity.getId());
+        Context.getPermissionsManager().checkPermission(Calendar.class, getUserId(), entity.getId());
         Context.getCalendarManager().updateItem(entity);
         return Response.ok(entity).build();
     }
@@ -84,7 +84,7 @@ public class CalendarResource extends BaseResource {
     @DELETE
     public Response remove(@PathParam("id") long id) throws SQLException {
         Context.getPermissionsManager().checkReadonly(getUserId());
-        Context.getPermissionsManager().checkPermission(Context.TYPE_CALENDAR, getUserId(), id);
+        Context.getPermissionsManager().checkPermission(Calendar.class, getUserId(), id);
         Context.getCalendarManager().removeItem(id);
         return Response.noContent().build();
     }
diff --git a/src/org/traccar/api/resource/DeviceResource.java b/src/org/traccar/api/resource/DeviceResource.java
index 285ed6a31..e1c0fc96d 100644
--- a/src/org/traccar/api/resource/DeviceResource.java
+++ b/src/org/traccar/api/resource/DeviceResource.java
@@ -77,7 +77,7 @@ public class DeviceResource extends BaseResource {
         Context.getPermissionsManager().checkDeviceReadonly(getUserId());
         Context.getPermissionsManager().checkDeviceLimit(getUserId());
         Context.getDeviceManager().addDevice(entity);
-        linkNew(entity);
+        linkNewEntity(entity);
         Context.getPermissionsManager().refreshPermissions();
         Context.getPermissionsManager().refreshAllExtendedPermissions();
         return Response.ok(entity).build();
diff --git a/src/org/traccar/api/resource/DriverResource.java b/src/org/traccar/api/resource/DriverResource.java
index b528a197a..cf80bf7df 100644
--- a/src/org/traccar/api/resource/DriverResource.java
+++ b/src/org/traccar/api/resource/DriverResource.java
@@ -86,7 +86,7 @@ public class DriverResource extends BaseResource {
     public Response add(Driver entity) throws SQLException {
         Context.getPermissionsManager().checkReadonly(getUserId());
         Context.getDriversManager().addItem(entity);
-        linkNew(entity);
+        linkNewEntity(entity);
         Context.getDriversManager().refreshUserItems();
         return Response.ok(entity).build();
     }
@@ -95,7 +95,7 @@ public class DriverResource extends BaseResource {
     @PUT
     public Response update(Driver entity) throws SQLException {
         Context.getPermissionsManager().checkReadonly(getUserId());
-        Context.getPermissionsManager().checkPermission(Context.TYPE_DRIVER, getUserId(), entity.getId());
+        Context.getPermissionsManager().checkPermission(Driver.class, getUserId(), entity.getId());
         Context.getDriversManager().updateItem(entity);
         return Response.ok(entity).build();
     }
@@ -104,7 +104,7 @@ public class DriverResource extends BaseResource {
     @DELETE
     public Response remove(@PathParam("id") long id) throws SQLException {
         Context.getPermissionsManager().checkReadonly(getUserId());
-        Context.getPermissionsManager().checkPermission(Context.TYPE_DRIVER, getUserId(), id);
+        Context.getPermissionsManager().checkPermission(Driver.class, getUserId(), id);
         Context.getDriversManager().removeItem(id);
         return Response.noContent().build();
     }
diff --git a/src/org/traccar/api/resource/EventResource.java b/src/org/traccar/api/resource/EventResource.java
index 85f981514..b7fda6f73 100644
--- a/src/org/traccar/api/resource/EventResource.java
+++ b/src/org/traccar/api/resource/EventResource.java
@@ -12,6 +12,7 @@ import javax.ws.rs.core.MediaType;
 import org.traccar.Context;
 import org.traccar.api.BaseResource;
 import org.traccar.model.Event;
+import org.traccar.model.Geofence;
 
 @Path("events")
 @Produces(MediaType.APPLICATION_JSON)
@@ -25,7 +26,7 @@ public class EventResource extends BaseResource {
         Event event = Context.getDataManager().getEvent(id);
         Context.getPermissionsManager().checkDevice(getUserId(), event.getDeviceId());
         if (event.getGeofenceId() != 0) {
-            Context.getPermissionsManager().checkPermission(Context.TYPE_GEOFENCE, getUserId(), event.getGeofenceId());
+            Context.getPermissionsManager().checkPermission(Geofence.class, getUserId(), event.getGeofenceId());
         }
         return event;
     }
diff --git a/src/org/traccar/api/resource/GeofenceResource.java b/src/org/traccar/api/resource/GeofenceResource.java
index c9cc72bd7..341180cf8 100644
--- a/src/org/traccar/api/resource/GeofenceResource.java
+++ b/src/org/traccar/api/resource/GeofenceResource.java
@@ -85,7 +85,7 @@ public class GeofenceResource extends BaseResource {
     public Response add(Geofence entity) throws SQLException {
         Context.getPermissionsManager().checkReadonly(getUserId());
         Context.getGeofenceManager().addItem(entity);
-        linkNew(entity);
+        linkNewEntity(entity);
         Context.getGeofenceManager().refreshUserItems();
         return Response.ok(entity).build();
     }
@@ -94,7 +94,7 @@ public class GeofenceResource extends BaseResource {
     @PUT
     public Response update(Geofence entity) throws SQLException {
         Context.getPermissionsManager().checkReadonly(getUserId());
-        Context.getPermissionsManager().checkPermission(Context.TYPE_GEOFENCE, getUserId(), entity.getId());
+        Context.getPermissionsManager().checkPermission(Geofence.class, getUserId(), entity.getId());
         Context.getGeofenceManager().updateItem(entity);
         return Response.ok(entity).build();
     }
@@ -103,7 +103,7 @@ public class GeofenceResource extends BaseResource {
     @DELETE
     public Response remove(@PathParam("id") long id) throws SQLException {
         Context.getPermissionsManager().checkReadonly(getUserId());
-        Context.getPermissionsManager().checkPermission(Context.TYPE_GEOFENCE, getUserId(), id);
+        Context.getPermissionsManager().checkPermission(Geofence.class, getUserId(), id);
         Context.getGeofenceManager().removeItem(id);
         return Response.noContent().build();
     }
diff --git a/src/org/traccar/api/resource/GroupResource.java b/src/org/traccar/api/resource/GroupResource.java
index 5d575ebfe..2ecd11fe5 100644
--- a/src/org/traccar/api/resource/GroupResource.java
+++ b/src/org/traccar/api/resource/GroupResource.java
@@ -61,7 +61,7 @@ public class GroupResource extends BaseResource {
     public Response add(Group entity) throws SQLException {
         Context.getPermissionsManager().checkReadonly(getUserId());
         Context.getDeviceManager().addGroup(entity);
-        linkNew(entity);
+        linkNewEntity(entity);
         Context.getPermissionsManager().refreshPermissions();
         Context.getPermissionsManager().refreshAllExtendedPermissions();
         return Response.ok(entity).build();
diff --git a/src/org/traccar/api/resource/PermissionsResource.java b/src/org/traccar/api/resource/PermissionsResource.java
index 707242cf1..515efbe41 100644
--- a/src/org/traccar/api/resource/PermissionsResource.java
+++ b/src/org/traccar/api/resource/PermissionsResource.java
@@ -17,7 +17,7 @@
 package org.traccar.api.resource;
 
 import java.sql.SQLException;
-import java.util.Map;
+import java.util.LinkedHashMap;
 
 import javax.ws.rs.Consumes;
 import javax.ws.rs.DELETE;
@@ -36,17 +36,17 @@ import org.traccar.api.BaseResource;
 public class PermissionsResource  extends BaseResource {
 
     @POST
-    public Response add(Map<String, Long> entity) throws SQLException {
+    public Response add(LinkedHashMap<String, Long> entity) throws SQLException, ClassNotFoundException {
         Context.getPermissionsManager().checkReadonly(getUserId());
-        handlePermission(entity, true);
+        checkAndLinkPermission(entity, true);
         Context.getPermissionsManager().refreshPermissions(entity);
         return Response.noContent().build();
     }
 
     @DELETE
-    public Response remove(Map<String, Long> entity) throws SQLException {
+    public Response remove(LinkedHashMap<String, Long> entity) throws SQLException, ClassNotFoundException {
         Context.getPermissionsManager().checkReadonly(getUserId());
-        handlePermission(entity, false);
+        checkAndLinkPermission(entity, false);
         Context.getPermissionsManager().refreshPermissions(entity);
         return Response.noContent().build();
     }
diff --git a/src/org/traccar/api/resource/UserResource.java b/src/org/traccar/api/resource/UserResource.java
index e710c940d..98395e3cc 100644
--- a/src/org/traccar/api/resource/UserResource.java
+++ b/src/org/traccar/api/resource/UserResource.java
@@ -17,6 +17,7 @@ package org.traccar.api.resource;
 
 import org.traccar.Context;
 import org.traccar.api.BaseResource;
+import org.traccar.model.ManagedUser;
 import org.traccar.model.User;
 
 import javax.annotation.security.PermitAll;
@@ -74,7 +75,7 @@ public class UserResource extends BaseResource {
         }
         Context.getPermissionsManager().addUser(entity);
         if (Context.getPermissionsManager().isManager(getUserId())) {
-            Context.getDataManager().linkObject("userId", getUserId(), "managedUserId", entity.getId(), true);
+            Context.getDataManager().linkObject(User.class, getUserId(), ManagedUser.class, entity.getId(), true);
         }
         Context.getPermissionsManager().refreshUserPermissions();
         if (Context.getNotificationManager() != null) {
diff --git a/src/org/traccar/database/DataManager.java b/src/org/traccar/database/DataManager.java
index 3bb367ece..80b9f98e9 100644
--- a/src/org/traccar/database/DataManager.java
+++ b/src/org/traccar/database/DataManager.java
@@ -268,17 +268,19 @@ public class DataManager {
                 .executeUpdate());
     }
 
-    public static String makeName(String object) {
-        return object.substring(0, 1).toUpperCase() + object.replace("Id", "").substring(1);
+    public static Class<?> getClassByName(String name) throws ClassNotFoundException {
+        return Class.forName("org.traccar.model."
+                + name.substring(0, 1).toUpperCase() + name.replace("Id", "").substring(1));
     }
 
-    public static String makeNameId(String object) {
-        return object.substring(0, 1).toLowerCase() + object.substring(1) + (object.indexOf("Id") == -1 ? "Id" : "");
+    public static String makeNameId(Class<?> clazz) {
+        String name = clazz.getSimpleName();
+        return name.substring(0, 1).toLowerCase() + name.substring(1) + (name.indexOf("Id") == -1 ? "Id" : "");
     }
 
-    public void linkObject(String owner, long ownerId, String property, long propertyId,
-            boolean link) throws SQLException {
-        String query = "database." + (!link ? "un" : "") + "link" + makeName(owner) + makeName(property);
+    public void linkObject(Class<?> owner, long ownerId, Class<?> property, long propertyId, boolean link)
+            throws SQLException {
+        String query = "database." + (link ? "link" : "unlink") + owner.getSimpleName() + property.getSimpleName();
         QueryBuilder queryBuilder = QueryBuilder.create(dataSource, getQuery(query));
 
         queryBuilder.setLong(makeNameId(owner), ownerId);
@@ -291,8 +293,9 @@ public class DataManager {
         return QueryBuilder.create(dataSource, getQuery(query)).executeQuery(clazz);
     }
 
-    public Collection<Map<String, Long>> getPermissions(String owner, String property) throws SQLException {
-        String query = "database.select" + makeName(owner) + makeName(property) + "s";
+    public Collection<Map<String, Long>> getPermissions(Class<? extends BaseModel> owner,
+            Class<? extends BaseModel> property) throws SQLException {
+        String query = "database.select" + owner.getSimpleName() + property.getSimpleName() + "s";
         return QueryBuilder.create(dataSource, getQuery(query)).executeMapQuery(Long.class);
     }
 
diff --git a/src/org/traccar/database/DriversManager.java b/src/org/traccar/database/DriversManager.java
index 8c35f3ddf..0dc2b102d 100644
--- a/src/org/traccar/database/DriversManager.java
+++ b/src/org/traccar/database/DriversManager.java
@@ -73,7 +73,7 @@ public class DriversManager extends ExtendedObjectManager {
     @Override
     public void removeItem(long driverId) throws SQLException {
         Driver cachedDriver = (Driver) getById(driverId);
-        getDataManager().removeObject(cachedDriver.getClass(), driverId);
+        getDataManager().removeObject(Driver.class, driverId);
         if (cachedDriver != null) {
             String driverUniqueId = cachedDriver.getUniqueId();
             removeCachedItem(driverId);
diff --git a/src/org/traccar/database/ExtendedObjectManager.java b/src/org/traccar/database/ExtendedObjectManager.java
index fce32fb41..8380b9da2 100644
--- a/src/org/traccar/database/ExtendedObjectManager.java
+++ b/src/org/traccar/database/ExtendedObjectManager.java
@@ -26,6 +26,7 @@ import java.util.concurrent.ConcurrentHashMap;
 import org.traccar.Context;
 import org.traccar.helper.Log;
 import org.traccar.model.Device;
+import org.traccar.model.Group;
 import org.traccar.model.BaseModel;
 
 public abstract class ExtendedObjectManager extends SimpleObjectManager {
@@ -79,23 +80,26 @@ public abstract class ExtendedObjectManager extends SimpleObjectManager {
             try {
 
                 Collection<Map<String, Long>> databaseGroupPermissions =
-                        getDataManager().getPermissions("Group", getBaseClassName());
+                        getDataManager().getPermissions(Group.class, getBaseClass());
 
                 clearGroupItems();
                 for (Map<String, Long> groupPermission : databaseGroupPermissions) {
-                    getGroupItems(groupPermission.get("groupId")).add(groupPermission.get(getBaseClassIdName()));
+                    getGroupItems(groupPermission.get(DataManager.makeNameId(Group.class)))
+                            .add(groupPermission.get(getBaseClassIdName()));
                 }
 
                 Collection<Map<String, Long>> databaseDevicePermissions =
-                        getDataManager().getPermissions("Device", getBaseClassName());
+                        getDataManager().getPermissions(Device.class, getBaseClass());
                 Collection<Device> allDevices = Context.getDeviceManager().getAllDevices();
 
                 clearDeviceItems();
                 deviceItemsWithGroups.clear();
 
                 for (Map<String, Long> devicePermission : databaseDevicePermissions) {
-                    getDeviceItems(devicePermission.get("deviceId")).add(devicePermission.get(getBaseClassIdName()));
-                    getAllDeviceItems(devicePermission.get("deviceId")).add(devicePermission.get(getBaseClassIdName()));
+                    getDeviceItems(devicePermission.get(DataManager.makeNameId(Device.class)))
+                            .add(devicePermission.get(getBaseClassIdName()));
+                    getAllDeviceItems(devicePermission.get(DataManager.makeNameId(Device.class)))
+                            .add(devicePermission.get(getBaseClassIdName()));
                 }
 
                 for (Device device : allDevices) {
diff --git a/src/org/traccar/database/PermissionsManager.java b/src/org/traccar/database/PermissionsManager.java
index 56a12e941..4008134ec 100644
--- a/src/org/traccar/database/PermissionsManager.java
+++ b/src/org/traccar/database/PermissionsManager.java
@@ -17,8 +17,13 @@ package org.traccar.database;
 
 import org.traccar.Context;
 import org.traccar.helper.Log;
+import org.traccar.model.Attribute;
+import org.traccar.model.Calendar;
 import org.traccar.model.Device;
+import org.traccar.model.Driver;
+import org.traccar.model.Geofence;
 import org.traccar.model.Group;
+import org.traccar.model.ManagedUser;
 import org.traccar.model.Server;
 import org.traccar.model.User;
 
@@ -109,8 +114,9 @@ public class PermissionsManager {
     public final void refreshUserPermissions() {
         userPermissions.clear();
         try {
-            for (Map<String, Long> permission : dataManager.getPermissions("User", "Permission")) {
-                getUserPermissions(permission.get("userId")).add(permission.get("managedUserId"));
+            for (Map<String, Long> permission : dataManager.getPermissions(User.class, User.class)) {
+                getUserPermissions(permission.get(DataManager.makeNameId(User.class)))
+                        .add(permission.get(DataManager.makeNameId(ManagedUser.class)));
             }
         } catch (SQLException error) {
             Log.warning(error);
@@ -123,20 +129,23 @@ public class PermissionsManager {
         try {
             GroupTree groupTree = new GroupTree(Context.getDeviceManager().getAllGroups(),
                     Context.getDeviceManager().getAllDevices());
-            for (Map<String, Long> groupPermission : dataManager.getPermissions("Group", "Permission")) {
-                Set<Long> userGroupPermissions = getGroupPermissions(groupPermission.get("userId"));
-                Set<Long> userDevicePermissions = getDevicePermissions(groupPermission.get("userId"));
-                userGroupPermissions.add(groupPermission.get("groupId"));
-                for (Group group : groupTree.getGroups(groupPermission.get("groupId"))) {
+            for (Map<String, Long> groupPermission : dataManager.getPermissions(User.class, Group.class)) {
+                Set<Long> userGroupPermissions = getGroupPermissions(groupPermission
+                        .get(DataManager.makeNameId(User.class)));
+                Set<Long> userDevicePermissions = getDevicePermissions(groupPermission
+                        .get(DataManager.makeNameId(User.class)));
+                userGroupPermissions.add(groupPermission.get(DataManager.makeNameId(Group.class)));
+                for (Group group : groupTree.getGroups(groupPermission.get(DataManager.makeNameId(Group.class)))) {
                     userGroupPermissions.add(group.getId());
                 }
-                for (Device device : groupTree.getDevices(groupPermission.get("groupId"))) {
+                for (Device device : groupTree.getDevices(groupPermission.get(DataManager.makeNameId(Group.class)))) {
                     userDevicePermissions.add(device.getId());
                 }
             }
 
-            for (Map<String, Long> devicePermission : dataManager.getPermissions("Device", "Permission")) {
-                getDevicePermissions(devicePermission.get("userId")).add(devicePermission.get("deviceId"));
+            for (Map<String, Long> devicePermission : dataManager.getPermissions(User.class, Device.class)) {
+                getDevicePermissions(devicePermission.get(DataManager.makeNameId(User.class)))
+                        .add(devicePermission.get(DataManager.makeNameId(Device.class)));
             }
 
             groupDevices.clear();
@@ -296,33 +305,26 @@ public class PermissionsManager {
         }
     }
 
-    public void checkPermission(String object, long userId, long objectId) throws SecurityException {
+    public void checkPermission(Class<?> object, long userId, long objectId)
+            throws SecurityException {
         SimpleObjectManager manager = null;
 
-        switch (DataManager.makeName(object)) {
-            case Context.TYPE_DEVICE:
-                checkDevice(userId, objectId);
-                break;
-            case Context.TYPE_GROUP:
-                checkGroup(userId, objectId);
-                break;
-            case Context.TYPE_USER:
-                checkUser(userId, objectId);
-                break;
-            case Context.TYPE_GEOFENCE:
-                manager = Context.getGeofenceManager();
-                break;
-            case Context.TYPE_ATTRIBUTE:
-                manager = Context.getAttributesManager();
-                break;
-            case Context.TYPE_DRIVER:
-                manager = Context.getDriversManager();
-                break;
-            case Context.TYPE_CALENDAR:
-                manager = Context.getCalendarManager();
-                break;
-            default:
-                throw new IllegalArgumentException("Unknown object type");
+        if (object.equals(Device.class)) {
+            checkDevice(userId, objectId);
+        } else if (object.equals(Group.class)) {
+            checkGroup(userId, objectId);
+        } else if (object.equals(User.class) || object.equals(ManagedUser.class)) {
+            checkUser(userId, objectId);
+        } else if (object.equals(Geofence.class)) {
+            manager = Context.getGeofenceManager();
+        } else if (object.equals(Attribute.class)) {
+            manager = Context.getAttributesManager();
+        } else if (object.equals(Driver.class)) {
+            manager = Context.getDriversManager();
+        } else if (object.equals(Calendar.class)) {
+            manager = Context.getCalendarManager();
+        } else {
+            throw new IllegalArgumentException("Unknown object type");
         }
 
         if (manager != null) {
@@ -347,31 +349,33 @@ public class PermissionsManager {
     }
 
     public void refreshPermissions(Map<String, Long> entity) {
-        if (entity.containsKey("userId")) {
-            if (entity.containsKey("deviceId") || entity.containsKey("groupId")) {
+        if (entity.containsKey(DataManager.makeNameId(User.class))) {
+            if (entity.containsKey(DataManager.makeNameId(Device.class))
+                    || entity.containsKey(DataManager.makeNameId(Group.class))) {
                 refreshPermissions();
                 refreshAllExtendedPermissions();
-            } else if (entity.containsKey("managedUserId")) {
+            } else if (entity.containsKey(DataManager.makeNameId(ManagedUser.class))) {
                 refreshUserPermissions();
-            } else if (entity.containsKey("geofenceId")) {
+            } else if (entity.containsKey(DataManager.makeNameId(Geofence.class))) {
                 if (Context.getGeofenceManager() != null) {
                     Context.getGeofenceManager().refreshUserItems();
                 }
-            } else if (entity.containsKey("driverId")) {
+            } else if (entity.containsKey(DataManager.makeNameId(Driver.class))) {
                 Context.getDriversManager().refreshUserItems();
-            } else if (entity.containsKey("attributeId")) {
+            } else if (entity.containsKey(DataManager.makeNameId(Attribute.class))) {
                 Context.getAttributesManager().refreshUserItems();
-            } else if (entity.containsKey("calendarId")) {
+            } else if (entity.containsKey(DataManager.makeNameId(Calendar.class))) {
                 Context.getCalendarManager().refreshUserItems();
             }
-        } else if (entity.containsKey("deviceId") || entity.containsKey("groupId")) {
-            if (entity.containsKey("geofenceId")) {
+        } else if (entity.containsKey(DataManager.makeNameId(Device.class))
+                || entity.containsKey(DataManager.makeNameId(Group.class))) {
+            if (entity.containsKey(DataManager.makeNameId(Geofence.class))) {
                 if (Context.getGeofenceManager() != null) {
                     Context.getGeofenceManager().refreshExtendedPermissions();
                 }
-            } else if (entity.containsKey("driverId")) {
+            } else if (entity.containsKey(DataManager.makeNameId(Driver.class))) {
                 Context.getDriversManager().refreshExtendedPermissions();
-            } else if (entity.containsKey("attributeId")) {
+            } else if (entity.containsKey(DataManager.makeNameId(Attribute.class))) {
                 Context.getAttributesManager().refreshExtendedPermissions();
             }
         }
diff --git a/src/org/traccar/database/SimpleObjectManager.java b/src/org/traccar/database/SimpleObjectManager.java
index c4fc0e97a..0db8af658 100644
--- a/src/org/traccar/database/SimpleObjectManager.java
+++ b/src/org/traccar/database/SimpleObjectManager.java
@@ -27,6 +27,7 @@ import java.util.concurrent.ConcurrentHashMap;
 import org.traccar.Context;
 import org.traccar.helper.Log;
 import org.traccar.model.BaseModel;
+import org.traccar.model.User;
 
 public abstract class SimpleObjectManager {
 
@@ -36,14 +37,12 @@ public abstract class SimpleObjectManager {
     private final Map<Long, Set<Long>> userItems = new ConcurrentHashMap<>();
 
     private Class<? extends BaseModel> baseClass;
-    private String baseClassName;
     private String baseClassIdName;
 
     protected SimpleObjectManager(DataManager dataManager, Class<? extends BaseModel> baseClass) {
         this.dataManager = dataManager;
         this.baseClass = baseClass;
-        baseClassName = baseClass.getSimpleName();
-        baseClassIdName = baseClassName.substring(0, 1).toLowerCase() + baseClassName.substring(1) + "Id";
+        baseClassIdName = DataManager.makeNameId(baseClass);
     }
 
     protected final DataManager getDataManager() {
@@ -54,10 +53,6 @@ public abstract class SimpleObjectManager {
         return baseClass;
     }
 
-    protected final String getBaseClassName() {
-        return baseClassName;
-    }
-
     protected final String getBaseClassIdName() {
         return baseClassIdName;
     }
@@ -111,8 +106,9 @@ public abstract class SimpleObjectManager {
         if (dataManager != null) {
             try {
                 clearUserItems();
-                for (Map<String, Long> permission : dataManager.getPermissions(baseClassName, "Permission")) {
-                    getUserItems(permission.get("userId")).add(permission.get(baseClassIdName));
+                for (Map<String, Long> permission : dataManager.getPermissions(User.class, baseClass)) {
+                    getUserItems(permission.get(DataManager.makeNameId(User.class)))
+                            .add(permission.get(baseClassIdName));
                 }
             } catch (SQLException error) {
                 Log.warning(error);
@@ -133,7 +129,7 @@ public abstract class SimpleObjectManager {
     public void removeItem(long itemId) throws SQLException {
         BaseModel item = getById(itemId);
         if (item != null) {
-            dataManager.removeObject(item.getClass(), itemId);
+            dataManager.removeObject(baseClass, itemId);
             removeCachedItem(itemId);
         }
         refreshUserItems();
diff --git a/src/org/traccar/model/ManagedUser.java b/src/org/traccar/model/ManagedUser.java
new file mode 100644
index 000000000..03c5ef48d
--- /dev/null
+++ b/src/org/traccar/model/ManagedUser.java
@@ -0,0 +1,21 @@
+/*
+ * Copyright 2017 Anton Tananaev (anton@traccar.org)
+ * Copyright 2017 Andrey Kunitsyn (andrey@traccar.org)
+ *
+ * Licensed 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.
+ */
+package org.traccar.model;
+
+public class ManagedUser extends User {
+
+}