Applying Commands Response correctly

src/command/CommandHandler.java

 package command;
 
 import java.io.IOException;
-import java.io.OutputStream;
 
 public interface CommandHandler {
-    void execute( OutputStream os) throws IOException;
+    byte [] execute( ) throws IOException;
 }

src/command/CommandInvoker.java

 package command;
 
 import java.io.IOException;
-import java.io.OutputStream;
 
 public class CommandInvoker {
-    public static void invoke(CommandHandler command,  OutputStream os) throws IOException {
-        command.execute(os);
+    public static byte[] invoke(CommandHandler command) throws IOException {
+        return command.execute();
     }
 }

src/command/EchoCommand.java

@@ -2,23 +2,17 @@ package command;
 
 import util.Response;
 
-import java.io.IOException;
-import java.io.OutputStream;
 import java.util.List;
 
 public class EchoCommand implements CommandHandler {
     private final List<String> args;
+
     public EchoCommand(List<String> args) {
         this.args = args;
     }
 
     @Override
-    public void execute(OutputStream os) {
-        try {
-            os.write(Response.getResponse(args.getFirst()));
-            os.flush();
-        } catch (IOException e) {
-            throw new RuntimeException(e);
-        }
+    public byte[] execute() {
+        return (Response.getResponse(args.getFirst()));
     }
 }

src/command/GetCommand.java

@@ -3,8 +3,6 @@ package command;
 import storage.Storage;
 import util.Response;
 
-import java.io.IOException;
-import java.io.OutputStream;
 import java.util.List;
 
 
@@ -17,19 +15,12 @@ public class GetCommand implements CommandHandler {
     }
 
     @Override
-    public void execute(OutputStream os) {
+    public byte[] execute() {
 
-        try {
         String response = storage.get(args.getFirst().toLowerCase());
         if (response == null || response.isEmpty() || response.isBlank()) {
-                os.write("$-1\r\n".getBytes());
-                os.flush();
-                return;
-            }
-            os.write(Response.getResponse(response));
-            os.flush();
-        } catch (IOException e) {
-            throw new RuntimeException(e);
+            return ("$-1\r\n".getBytes());
         }
+        return (Response.getResponse(response));
     }
 }

src/command/PingCommand.java

@@ -3,18 +3,10 @@ package command;
 
 import model.Command;
 
-import java.io.IOException;
-import java.io.OutputStream;
-
 public class PingCommand implements CommandHandler {
 
     @Override
-    public void execute(OutputStream os) {
-        try {
-            os.write(("+" + Command.PONG.getValue() + "\r\n").getBytes());
-            os.flush();
-        } catch (IOException e) {
-            throw new RuntimeException(e);
-        }
+    public byte[] execute() {
+        return (("+" + Command.PONG.getValue() + "\r\n").getBytes());
     }
 }
\ No newline at end of file

src/command/SetCommand.java

@@ -3,8 +3,6 @@ package command;
 import model.Command;
 import storage.Storage;
 
-import java.io.IOException;
-import java.io.OutputStream;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
@@ -18,7 +16,7 @@ public class SetCommand implements CommandHandler {
     }
 
     @Override
-    public void execute(OutputStream os) {
+    public byte[] execute() {
 
         Map<String, String> commandsMap = new HashMap<>();
 
@@ -40,11 +38,7 @@ public class SetCommand implements CommandHandler {
             storage.save(args.getFirst().toLowerCase(), value);
         }
 
-        try {
-            os.write("+OK\r\n".getBytes());
-            os.flush();
-        } catch (IOException e) {
-            throw new RuntimeException(e);
-        }
+        return ("+OK\r\n".getBytes());
+
     }
 }

src/command/UnknownCommand.java

 package command;
 
-import java.io.IOException;
-import java.io.OutputStream;
 
 public class UnknownCommand implements CommandHandler {
     @Override
-    public void execute(OutputStream os) {
-        try {
-            os.write(("-" + "Unknown Command" + "\r\n").getBytes());
-            os.flush();
-        } catch (IOException e) {
-            throw new RuntimeException(e);
-        }
+    public byte[] execute() {
+        return (("-" + "Unknown Command" + "\r\n").getBytes());
     }
 }

src/handlers/ClientCommandHandler.java

@@ -26,7 +26,9 @@ public class ClientCommandHandler {
         commands.removeFirst();
         CommandHandler commandProcessor = factory.getCommand(command, commands);
         try {
-            CommandInvoker.invoke(commandProcessor, os);
+            byte[] result = CommandInvoker.invoke(commandProcessor);
+            os.write(result);
+            os.flush();
         } catch (IOException e) {
             throw new RuntimeException(e);
         }

src/storage/Storage.java

@@ -62,6 +62,7 @@ public class Storage {
         timeToExpiration.remove(key);
         currentTimeForKey.remove(key);
     }
+
     void runCachePolicy() {
         storage.runMaintenance();
     }

src/storage/StorageManager.java

@@ -14,6 +14,7 @@ public class StorageManager {
         this.scheduler = Executors.newSingleThreadScheduledExecutor();
         scheduler.scheduleAtFixedRate(this::performMaintenance, 2, 2, TimeUnit.MINUTES);
     }
+
     private void performMaintenance() {
         storage.runCachePolicy();
         System.out.println("Maintenance performed at: " + Date.from(java.time.Clock.systemUTC().instant()));