Persisting cache in PersistentLocalDb

src/main/java/envoy/client/data/Cache.java

@@ -1,5 +1,6 @@
 package envoy.client.data;
 
+import java.io.Serializable;
 import java.util.LinkedList;
 import java.util.Queue;
 import java.util.function.Consumer;
@@ -18,12 +19,13 @@ import envoy.client.util.EnvoyLog;
  * @author Kai S. K. Engelbart
  * @since Envoy v0.3-alpha
  */
-public class Cache<T> implements Consumer<T> {
+public class Cache<T> implements Consumer<T>, Serializable {
 
 	private final Queue<T>			elements	= new LinkedList<>();
 	private transient Consumer<T>	processor;
 
 	private static final Logger logger = EnvoyLog.getLogger(Cache.class.getSimpleName());
+	private static final long	serialVersionUID	= 7343544675545545076L;
 
 	/**
 	 * Adds an element to the cache.

src/main/java/envoy/client/data/LocalDb.java

@@ -24,8 +24,8 @@ public abstract class LocalDb {
 	protected Map<String, User>					users	= new HashMap<>();
 	protected List<Chat>						chats	= new ArrayList<>();
 	protected IdGenerator						idGenerator;
-	protected Cache<Message>					messageCache;
-	protected Cache<MessageStatusChangeEvent>	statusCache;
+	protected Cache<Message>					messageCache	= new Cache<>();
+	protected Cache<MessageStatusChangeEvent>	statusCache		= new Cache<>();
 
 	/**
 	 * Initializes a storage space for a user-specific list of chats.
@@ -52,12 +52,12 @@ public abstract class LocalDb {
 	public void loadUsers() throws Exception {}
 
 	/**
-	 * Loads all chat data of the client user.
+	 * Loads all data of the client user.
 	 *
 	 * @throws Exception if the loading process failed
 	 * @since Envoy v0.3-alpha
 	 */
-	public void loadChats() throws Exception {}
+	public void loadUserData() throws Exception {}
 
 	/**
 	 * Loads the ID generator. Any exception thrown during this process is ignored.

src/main/java/envoy/client/data/PersistentLocalDb.java

@@ -23,7 +23,7 @@ import envoy.util.SerializationUtils;
  */
 public class PersistentLocalDb extends LocalDb {
 
-	private File localDBDir, localDBFile, usersFile, idGeneratorFile;
+	private File localDBDir, localDBFile, usersFile, idGeneratorFile, messageCacheFile, statusCacheFile;
 
 	/**
 	 * Initializes an empty local database without a directory. All changes made to
@@ -63,7 +63,9 @@ public class PersistentLocalDb extends LocalDb {
 	@Override
 	public void initializeUserStorage() {
 		if (user == null) throw new NullPointerException("Client user is null");
-		localDBFile = new File(localDBDir, user.getId() + ".db");
+		localDBFile			= new File(localDBDir, user.getId() + ".db");
+		messageCacheFile	= new File(localDBDir, user.getId() + "_message_cache.db");
+		statusCacheFile		= new File(localDBDir, user.getId() + "_status_cache.db");
 	}
 
 	@Override
@@ -71,8 +73,12 @@ public class PersistentLocalDb extends LocalDb {
 		// Save users
 		SerializationUtils.write(usersFile, users);
 
-		// Save chats
-		if (user != null) SerializationUtils.write(localDBFile, chats);
+		// Save user data
+		if (user != null) {
+			SerializationUtils.write(localDBFile, chats);
+			SerializationUtils.write(messageCacheFile, messageCache);
+			SerializationUtils.write(statusCacheFile, statusCache);
+		}
 
 		// Save id generator
 		if (hasIdGenerator()) SerializationUtils.write(idGeneratorFile, idGenerator);
@@ -82,7 +88,11 @@ public class PersistentLocalDb extends LocalDb {
 	public void loadUsers() throws ClassNotFoundException, IOException { users = SerializationUtils.read(usersFile, HashMap.class); }
 
 	@Override
-	public void loadChats() throws ClassNotFoundException, IOException { chats = SerializationUtils.read(localDBFile, ArrayList.class); }
+	public void loadUserData() throws ClassNotFoundException, IOException {
+		chats			= SerializationUtils.read(localDBFile, ArrayList.class);
+		messageCache	= SerializationUtils.read(messageCacheFile, Cache.class);
+		statusCache		= SerializationUtils.read(statusCacheFile, Cache.class);
+	}
 
 	@Override
 	public void loadIdGenerator() {

src/main/java/envoy/client/ui/Startup.java

@@ -138,7 +138,7 @@ public class Startup {
 		// Initialize chats in local database
 		try {
 			localDb.initializeUserStorage();
-			localDb.loadChats();
+			localDb.loadUserData();
 		} catch (FileNotFoundException e) {
 			// The local database file has not yet been created, probably first login
 		} catch (Exception e) {