Add abstraction for reading and writing to account files with differe…

…nt formats

application/accounts.json

@@ -0,0 +1,25 @@
+[
+  {
+    "username": "test2",
+    "homeDirectory": "C:\\Users\\wkacp\\Desktop"
+  },
+  {
+    "username": "admin",
+    "homeDirectory": "test",
+    "hashedPassword": "7ee737c83ee689c96ef37d3a029068c390ebc8f8"
+  },
+  {
+    "username": "admin2",
+    "homeDirectory": "test",
+    "hashedPassword": "7ee737c83ee689c96ef37d3a029068c390ebc8f8"
+  },
+  {
+    "username": "admin3",
+    "homeDirectory": "test",
+    "hashedPassword": "7ee737c83ee689c96ef37d3a029068c390ebc8f8"
+  },
+  {
+    "username": "sd",
+    "homeDirectory": ""
+  }
+]

server/src/main/java/com/ftprx/server/Server.java

@@ -16,6 +16,7 @@
 
 package com.ftprx.server;
 
+import com.ftprx.server.account.AccountFileFormat;
 import com.ftprx.server.account.ObservableAccountRepository;
 import com.ftprx.server.channel.Client;
 import com.ftprx.server.repository.FileAccountRepository;
@@ -51,7 +52,7 @@ public class Server {
 
     private Server() {
         this.clients = new CopyOnWriteArrayList<>();
-        this.accountRepository = new FileAccountRepository("users.ftprx");
+        this.accountRepository = new FileAccountRepository("accounts.json", AccountFileFormat.JSON);
         this.status = ServerStatus.STOPPED;
         this.config = ConfigFactory.create(ServerConfig.class);
     }

server/src/main/java/com/ftprx/server/account/AccountFileFormat.java

@@ -0,0 +1,5 @@
+package com.ftprx.server.account;
+
+public enum AccountFileFormat {
+    JSON
+}

server/src/main/java/com/ftprx/server/account/AccountFileManager.java

@@ -0,0 +1,15 @@
+package com.ftprx.server.account;
+
+import com.ftprx.server.account.Account;
+
+import java.io.Reader;
+import java.io.Writer;
+import java.util.List;
+
+/**
+ * An interface for reading from and writing to a file containing account list.
+ */
+public interface AccountFileManager {
+    void write(Writer writer, List<Account> accounts);
+    List<Account> read(Reader reader);
+}

server/src/main/java/com/ftprx/server/account/JsonAccountFileManager.java

@@ -0,0 +1,26 @@
+package com.ftprx.server.account;
+
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+
+import java.io.Reader;
+import java.io.Writer;
+import java.util.List;
+
+public class JsonAccountFileManager implements AccountFileManager {
+    private final Gson gson;
+
+    public JsonAccountFileManager() {
+        this.gson = new GsonBuilder().setPrettyPrinting().create();
+    }
+
+    @Override
+    public void write(Writer writer, List<Account> accounts) {
+        gson.toJson(accounts, writer);
+    }
+
+    @Override
+    public List<Account> read(Reader reader) {
+        return List.of(gson.fromJson(reader, Account[].class));
+    }
+}

server/src/main/java/com/ftprx/server/repository/FileAccountRepository.java

@@ -17,31 +17,33 @@
 package com.ftprx.server.repository;
 
 import com.ftprx.server.account.*;
-import com.google.gson.Gson;
-import com.google.gson.GsonBuilder;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.tinylog.Logger;
 
-import java.io.*;
+import java.io.Reader;
+import java.io.Writer;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.*;
 import java.util.concurrent.ConcurrentHashMap;
 
 import static com.ftprx.server.account.AccountInsertException.ACCOUNT_ALREADY_EXISTS;
 import static java.nio.file.Files.*;
+import static java.util.Collections.emptyList;
 
 public class FileAccountRepository implements ObservableAccountRepository {
-    private final Gson gson;
-    private final Path repositoryFile;
+    private final Path accountsFile;
     private final Set<AccountRepositoryChangeListener> listeners;
+    private final AccountFileManager fileManager;
 
-    public FileAccountRepository(String filename) {
-        this.repositoryFile = Paths.get(filename);
-        this.gson = new GsonBuilder()
-                .setPrettyPrinting()
-                .create();
+    public FileAccountRepository(String filename, AccountFileFormat fileFormat) {
+        this.accountsFile = Paths.get(filename);
+
+        switch (fileFormat) {
+            case JSON -> fileManager = new JsonAccountFileManager();
+            default -> throw new IllegalStateException("Unexpected value: " + fileFormat);
+        }
 
         listeners = Collections.newSetFromMap(new ConcurrentHashMap<>());
 
@@ -50,9 +52,7 @@ public FileAccountRepository(String filename) {
             insert(new Account("admin", "test", "dir"));
             insert(new Account("admin2", "test", "dir"));
             insert(new Account("admin3", "test", "dir"));
-        } catch (AccountInsertException ignore) {} catch (AccountCreateException e) {
-            e.printStackTrace();
-        }
+        } catch (AccountInsertException | AccountCreateException ignore) {}
     }
 
     @Override
@@ -119,32 +119,32 @@ private void delete(String username) {
         saveFile(toSave);
     }
 
-    private void createRepositoryFileIfNotExists() {
-        if (!exists(repositoryFile)) {
+    private void createAccountsFileIfNotExists() {
+        if (!exists(accountsFile)) {
             Logger.debug("Account file not found!");
             try {
-                createFile(repositoryFile);
+                createFile(accountsFile);
             } catch (Exception e) {
                 Logger.error(e.getMessage());
             }
         }
     }
 
     private void saveFile(List<Account> accounts) {
-        createRepositoryFileIfNotExists();
-        try (Writer writer = newBufferedWriter(repositoryFile)) {
-            gson.toJson(accounts, writer);
+        createAccountsFileIfNotExists();
+        try (Writer writer = newBufferedWriter(accountsFile)) {
+            fileManager.write(writer, accounts);
         } catch (Exception e) {
             Logger.error(e.getMessage());
         }
     }
 
     public List<Account> readFile() {
-        createRepositoryFileIfNotExists();
-        try (Reader reader = newBufferedReader(repositoryFile)) {
-            return Arrays.asList(gson.fromJson(reader, Account[].class));
+        createAccountsFileIfNotExists();
+        try (Reader reader = newBufferedReader(accountsFile)) {
+            return fileManager.read(reader);
         } catch (Exception e) {
-            return Collections.emptyList();
+            return emptyList();
         }
     }
 

server/src/main/java/com/ftprx/server/repository/InMemoryAccountRepository.java

@@ -9,7 +9,7 @@
 import java.util.List;
 
 public class InMemoryAccountRepository implements AccountRepository {
-    private List<Account> accounts = new ArrayList<>();
+    private final List<Account> accounts = new ArrayList<>();
 
     public InMemoryAccountRepository() {
         try {