using new communication between layers - getting rid of exception driven notifications

Author: keinproblem

sampling-message-client/src/main/java/de/dhbw/ravensburg/verteiltesysteme/client/CommandLineClient.java

@@ -59,7 +59,7 @@ public class CommandLineClient {
                 .build());
     }
 
-    public void run(String[] args) throws Exception {
+    public void run(String[] args) {
         CommandLineParser commandLineParser = new DefaultParser();
         helpFormatter = new HelpFormatter();
         CommandLine commandLine;
@@ -198,7 +198,8 @@ private void deleteSamplingMessage(CommandLine commandLine, SamplingMessageGrpc.
 
 
     private void exitWithError(String errorMessage) {
-        System.out.println(errorMessage);
+        log.debug("ParsingError: ", errorMessage);
+        log.error(errorMessage);
         helpFormatter.printHelp("sampling-message-client", options);
         System.exit(1);
     }

sampling-message-server/src/main/java/de/dhbw/ravensburg/verteiltesysteme/server/persistence/DatabaseAccessObject.java

@@ -1,20 +1,19 @@
 package de.dhbw.ravensburg.verteiltesysteme.server.persistence;
 
-import de.dhbw.ravensburg.verteiltesysteme.server.persistence.exception.DatabaseSamplingMessageAlreadyExistsException;
-import de.dhbw.ravensburg.verteiltesysteme.server.persistence.exception.DatabaseSamplingMessageNotFoundException;
 import de.dhbw.ravensburg.verteiltesysteme.server.persistence.model.DatabaseSamplingMessage;
 import lombok.NonNull;
 
 import java.time.Instant;
+import java.util.Optional;
 
 public interface DatabaseAccessObject {
-    DatabaseSamplingMessage getSamplingMessage(@NonNull String messageName) throws DatabaseSamplingMessageNotFoundException;
+    Optional<DatabaseSamplingMessage> getSamplingMessage(@NonNull String messageName);
 
-    void createSamplingMessage(@NonNull String messageName, @NonNull DatabaseSamplingMessage databaseSamplingMessage) throws DatabaseSamplingMessageAlreadyExistsException;
+    boolean createSamplingMessage(@NonNull String messageName, @NonNull DatabaseSamplingMessage databaseSamplingMessage);
 
-    void writeSamplingMessageContentAndTimestamp(@NonNull final String messageName, @NonNull final String messageContent, @NonNull final Instant updateTimestamp) throws DatabaseSamplingMessageNotFoundException;
+    boolean writeSamplingMessageContentAndTimestamp(@NonNull final String messageName, @NonNull final String messageContent, @NonNull final Instant updateTimestamp);
 
-    void deleteSamplingMessage(@NonNull String messageName) throws DatabaseSamplingMessageNotFoundException;
+    boolean deleteSamplingMessage(@NonNull String messageName);
 
     long getTotalMessageCount();
 }

sampling-message-server/src/main/java/de/dhbw/ravensburg/verteiltesysteme/server/persistence/DatabaseAccessObjectImpl.java

@@ -1,49 +1,54 @@
 package de.dhbw.ravensburg.verteiltesysteme.server.persistence;
 
-import de.dhbw.ravensburg.verteiltesysteme.server.persistence.exception.DatabaseSamplingMessageAlreadyExistsException;
-import de.dhbw.ravensburg.verteiltesysteme.server.persistence.exception.DatabaseSamplingMessageNotFoundException;
 import de.dhbw.ravensburg.verteiltesysteme.server.persistence.model.DatabaseSamplingMessage;
 import lombok.NonNull;
 import lombok.extern.slf4j.Slf4j;
 
 import java.time.Instant;
+import java.util.Optional;
 
 @Slf4j
 public class DatabaseAccessObjectImpl implements DatabaseAccessObject {
     private final FakePersistence<String, DatabaseSamplingMessage> fakePersistence;
 
     public DatabaseAccessObjectImpl(final @NonNull FakePersistence<String, DatabaseSamplingMessage> fakePersistence) {
+        log.debug("Constructing DatabaseAccessObjectImpl");
         this.fakePersistence = fakePersistence;
     }
 
     @Override
-    public DatabaseSamplingMessage getSamplingMessage(@NonNull final String messageName) throws DatabaseSamplingMessageNotFoundException {
+    public Optional<DatabaseSamplingMessage> getSamplingMessage(@NonNull final String messageName) {
         final DatabaseSamplingMessage databaseSamplingMessage = fakePersistence.get(messageName);
         if (databaseSamplingMessage == null) {
-            throw new DatabaseSamplingMessageNotFoundException(String.format("DatabaseSamplingMessage with the messageName: %s not found.", messageName));
+            log.info(String.format("DatabaseSamplingMessage with the messageName: %s not found.", messageName));
         }
-        return databaseSamplingMessage;
+        return Optional.of(databaseSamplingMessage);
     }
 
     @Override
-    public void createSamplingMessage(@NonNull final String messageName, @NonNull final DatabaseSamplingMessage databaseSamplingMessage) throws DatabaseSamplingMessageAlreadyExistsException {
-        if (fakePersistence.putIfAbsent(messageName, databaseSamplingMessage) != null) {
-            throw new DatabaseSamplingMessageAlreadyExistsException(String.format("DatabaseSamplingMessage with the messageName: %s already exists.", messageName));
+    public boolean createSamplingMessage(@NonNull final String messageName, @NonNull final DatabaseSamplingMessage databaseSamplingMessage) {
+        if (fakePersistence.putIfAbsent(messageName, databaseSamplingMessage) == null) {
+            return true;
         }
+        log.info(String.format("DatabaseSamplingMessage with the messageName: %s already exists.", messageName));
+        return false;
     }
 
-    public void writeSamplingMessageContentAndTimestamp(@NonNull final String messageName, @NonNull final String messageContent, @NonNull final Instant updateTimestamp) throws DatabaseSamplingMessageNotFoundException {
-        if (fakePersistence.computeIfPresent(messageName, (key, value) -> value.setMessageContent(messageContent).setMessageUpdateTimestamp(updateTimestamp)) == null) {
-            throw new DatabaseSamplingMessageNotFoundException(String.format("DatabaseSamplingMessage with the messageName: %s not found.", messageName));
+    public boolean writeSamplingMessageContentAndTimestamp(@NonNull final String messageName, @NonNull final String messageContent, @NonNull final Instant updateTimestamp) {
+        if (fakePersistence.computeIfPresent(messageName, (key, value) -> value.setMessageContent(messageContent).setMessageUpdateTimestamp(updateTimestamp)) != null) {
+            return true;
         }
-        log.info(fakePersistence.get(messageName).toString());
+        log.info(String.format("DatabaseSamplingMessage with the messageName: %s not found.", messageName));
+        return false;
     }
 
     @Override
-    public void deleteSamplingMessage(@NonNull final String messageName) throws DatabaseSamplingMessageNotFoundException {
-        if (fakePersistence.remove(messageName) == null) {
-            throw new DatabaseSamplingMessageNotFoundException(String.format("DatabaseSamplingMessage with the messageName: %s not found.", messageName));
+    public boolean deleteSamplingMessage(@NonNull final String messageName) {
+        if (fakePersistence.remove(messageName) != null) {
+            return true;
         }
+        log.info(String.format("DatabaseSamplingMessage with the messageName: %s not found.", messageName));
+        return false;
     }
 
     @Override