active client connection handling and find-bugs

findbugs-excludes.xml

@@ -12,9 +12,11 @@
         <Package name="ch.ethz.seb.sebserver.webservice.datalayer.batis.model"/>
     </Match>
     <Match>
-      <Class name="ch.ethz.seb.sebserver.gui.widget.MultiSelectionCombo" />
+      <Package name="ch.ethz.seb.sebserver.gui.widget" />
-      <Class name="ch.ethz.seb.sebserver.gui.widget.GridTable" />
       <Bug pattern="SE_BAD_FIELD" />
     </Match>
+    
+    
+    
 
 </FindBugsFilter>

src/main/java/ch/ethz/seb/sebserver/webservice/servicelayer/session/ExamSessionService.java

@@ -47,14 +47,21 @@ public interface ExamSessionService {
     void streamDefaultExamConfig(String connectionToken, OutputStream out);
 
     /** Get current ClientConnectionData for a specified active SEB client connection.
-     * 
+     *
+     * active SEB client connections are connections that were initialized by a SEB client
+     * on the particular server instance.
+     *
      * @param connectionToken the connection token of the active SEB client connection
      * @return */
     Result<ClientConnectionData> getConnectionData(String connectionToken);
 
     /** Get the collection of ClientConnectionData of all active SEB client connections
      * of a running exam.
-     * 
+     *
+     * active SEB client connections are connections that were initialized by a SEB client
+     * on the particular server instance. This may not be the all connections of an exam but
+     * a subset of them.
+     *
      * @param examId The exam identifier
      * @return collection of ClientConnectionData of all active SEB client connections
      *         of a running exam */

src/main/java/ch/ethz/seb/sebserver/webservice/servicelayer/session/SebClientConnectionService.java

@@ -9,7 +9,6 @@
 package ch.ethz.seb.sebserver.webservice.servicelayer.session;
 
 import ch.ethz.seb.sebserver.gbl.model.session.ClientConnection;
-import ch.ethz.seb.sebserver.gbl.model.session.ClientConnectionData;
 import ch.ethz.seb.sebserver.gbl.model.session.ClientEvent;
 import ch.ethz.seb.sebserver.gbl.util.Result;
 
@@ -100,12 +99,6 @@ public interface SebClientConnectionService {
             Long institutionId,
             String clientAddress);
 
-    /** Get ClientConnectionData for an active connection (connection on running exam)
-     *
-     * @param connectionToken The connection token of the connection to get the ClientConnectionData from
-     * @return ClientConnectionData for an active connection (connection on running exam) */
-    Result<ClientConnectionData> getActiveConnectionData(String connectionToken);
-
     /** Notify a ping for a certain client connection.
      *
      * @param connectionToken the connection token

src/main/java/ch/ethz/seb/sebserver/webservice/servicelayer/session/impl/ExamSessionServiceImpl.java

@@ -17,6 +17,8 @@ import java.util.stream.Collectors;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+import org.springframework.cache.Cache;
+import org.springframework.cache.CacheManager;
 import org.springframework.context.annotation.Lazy;
 import org.springframework.security.access.AccessDeniedException;
 import org.springframework.stereotype.Service;
@@ -40,15 +42,18 @@ public class ExamSessionServiceImpl implements ExamSessionService {
     private final ClientConnectionDAO clientConnectionDAO;
     private final ExamSessionCacheService examSessionCacheService;
     private final ExamDAO examDAO;
+    private final CacheManager cacheManager;
 
     protected ExamSessionServiceImpl(
             final ExamSessionCacheService examSessionCacheService,
             final ExamDAO examDAO,
-            final ClientConnectionDAO clientConnectionDAO) {
+            final ClientConnectionDAO clientConnectionDAO,
+            final CacheManager cacheManager) {
 
         this.examSessionCacheService = examSessionCacheService;
         this.examDAO = examDAO;
         this.clientConnectionDAO = clientConnectionDAO;
+        this.cacheManager = cacheManager;
     }
 
     @Override
@@ -147,25 +152,24 @@ public class ExamSessionServiceImpl implements ExamSessionService {
 
     @Override
     public Result<ClientConnectionData> getConnectionData(final String connectionToken) {
-        final ClientConnectionDataInternal activeClientConnection = this.examSessionCacheService
+        return Result.tryCatch(() -> {
-                .getActiveClientConnection(connectionToken);
+            final Cache cache = this.cacheManager.getCache(ExamSessionCacheService.CACHE_NAME_ACTIVE_CLIENT_CONNECTION);
-
+            return cache.get(connectionToken, ClientConnectionData.class);
-        if (activeClientConnection == null) {
+        });
-            log.error("No active ClientConnection found for token: {}", connectionToken);
-            return Result.ofError(new IllegalArgumentException("No active ClientConnection found for token"));
-        } else {
-            return Result.of(activeClientConnection);
-        }
     }
 
     @Override
     public Result<Collection<ClientConnectionData>> getConnectionData(final Long examId) {
-        return this.clientConnectionDAO
+        return Result.tryCatch(() -> {
-                .getConnectionTokens(examId)
+            final Cache cache = this.cacheManager.getCache(ExamSessionCacheService.CACHE_NAME_ACTIVE_CLIENT_CONNECTION);
-                .map(all -> all
+            return this.clientConnectionDAO
-                        .stream()
+                    .getConnectionTokens(examId)
-                        .map(this.examSessionCacheService::getActiveClientConnection)
+                    .getOrThrow()
-                        .collect(Collectors.toList()));
+                    .stream()
+                    .map(token -> cache.get(token, ClientConnectionData.class))
+                    .filter(data -> data != null)
+                    .collect(Collectors.toList());
+        });
     }
 
     private void flushCache(final Exam exam) {

src/main/java/ch/ethz/seb/sebserver/webservice/servicelayer/session/impl/SebClientConnectionServiceImpl.java

@@ -20,7 +20,6 @@ import org.springframework.stereotype.Service;
 import ch.ethz.seb.sebserver.gbl.model.exam.Exam.ExamType;
 import ch.ethz.seb.sebserver.gbl.model.session.ClientConnection;
 import ch.ethz.seb.sebserver.gbl.model.session.ClientConnection.ConnectionStatus;
-import ch.ethz.seb.sebserver.gbl.model.session.ClientConnectionData;
 import ch.ethz.seb.sebserver.gbl.model.session.ClientEvent;
 import ch.ethz.seb.sebserver.gbl.profile.WebServiceProfile;
 import ch.ethz.seb.sebserver.gbl.util.Result;
@@ -339,19 +338,6 @@ public class SebClientConnectionServiceImpl implements SebClientConnectionServic
         });
     }
 
-    @Override
-    public Result<ClientConnectionData> getActiveConnectionData(final String connectionToken) {
-        final ClientConnectionDataInternal activeClientConnection = this.examSessionCacheService
-                .getActiveClientConnection(connectionToken);
-
-        if (activeClientConnection == null) {
-            return Result
-                    .ofError(new IllegalArgumentException("No active client connection found for connectionToken"));
-        } else {
-            return Result.of(activeClientConnection);
-        }
-    }
-
     @Override
     public void notifyPing(
             final String connectionToken,

src/main/java/ch/ethz/seb/sebserver/webservice/weblayer/api/ExamAPI_V1_Controller.java

@@ -259,8 +259,8 @@ public class ExamAPI_V1_Controller {
                 handshakeUpdate(connectionToken, Long.valueOf(examId), null, principal, request);
             }
 
-            final ClientConnectionData connection = this.sebClientConnectionService
+            final ClientConnectionData connection = this.examSessionService
-                    .getActiveConnectionData(connectionToken)
+                    .getConnectionData(connectionToken)
                     .getOrThrow();
 
             // exam integrity check