是否可以将小程序用作Java的服务器？

Question

我刚刚进入网络，对于如何使用服务器托管公司的服务器进行游戏感到非常困惑。 目前，该程序允许用户从其计算机托管服务器，并且在一定程度上可以正常工作。 唯一的问题是，当我的朋友从其他国家/地区连接到游戏时，他们的ping值非常高，并且非常落后。

我现在正在使用一个提供免费网络托管空间的网站。 我相信我已经跳过了使用套接字所需的大多数权限限制，并且applet的运行方式与在计算机上运行时的运行方式一样。

以下是Game类的摘录。 如果我使用InetAddress.getLocalHost（）。getHostAddress（）来获取IP，它将从使用客户端的用户那里获取IP，并将其作为服务器主机。 这行得通，但是并不能解决我的滞后问题。

    Game.java

    public synchronized void start() {
    running = true;

    thread = new Thread(this, NAME + "_main");
    thread.start();

    if (JOptionPane.showConfirmDialog(this, "Do you want to run the server") == 0) {
        socketServer = new GameServer(this);
        socketServer.start();
    }


    this.ipAddress = "31.170.163.198";
    //this.ipAddress = InetAddress.getByName(ipAddress).toString();

    System.out.println("IP: " + this.ipAddress);
    socketClient = new GameClient(this, this.ipAddress);//Inet4Address.getLocalHost().getHostAddress());    

    try {
        Player.setIp(Inet4Address.getLocalHost().getHostAddress());
    } catch (UnknownHostException e) {
        e.printStackTrace();
    }
    socketClient.start();
}

我希望包含jar的服务器托管该服务器。 我们所有人都相互ping测试，并且大多数人都超时了，但是，当我们ping服务器的ip时，我们都得到了不错的ping。 当我手动输入服务器的IP（在控制面板中找到此信息）时，服务器/客户端无法建立连接。 我尝试使用提供的网站IP和服务器IP。 我还尝试使用applet.getCodeBase（）。getHost（）以便从服务器检索IP，但是该IP也无法发送/接收数据。

我想做的事可能吗？ 服务器是否阻止了我以这种方式使用它？ 我是否需要重写整个程序并查看java servlet以实现我的目标？

我很抱歉这个问题很愚蠢。 在过去的3-4天中，我一直在为此工作，但进展甚微。 我已经以这种方式使用服务器进行了一些搜索，但在该主题上我发现得很少。

以下是其他相关代码段的摘录。

GameClient.java

package fraccas.java2dgame.net;


public class GameClient extends Thread {

private InetAddress ipAddress;
private DatagramSocket socket;
private Game game;
public long lastPing = 0;
public static int ping = 0;

public GameClient(Game game, String ipAddress) {
    this.game = game;
    try {
        this.socket = new DatagramSocket();
        this.ipAddress = InetAddress.getByName(ipAddress);
        System.out.println("IP: " + InetAddress.getByName(ipAddress));
    } catch (SocketException e) {
        e.printStackTrace();
    } catch (UnknownHostException e) {
        e.printStackTrace();
    }
}

public void run() {
    while (true) {
        byte[] data = new byte[1024];
        DatagramPacket packet = new DatagramPacket(data, data.length);
        try {
            socket.receive(packet);
            if (packet != null)
            {
                long current = System.currentTimeMillis();
                ping = (int) (current - lastPing);
                lastPing = current;
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        this.parsePacket(packet.getData(), packet.getAddress(), packet.getPort());
    }
}

private void parsePacket(byte[] data, InetAddress address, int port) {
    String message = new String(data).trim();
    PacketTypes type = Packet.lookupPacket(message.substring(0, 2));
    Packet packet = null;
    switch (type) {
    default:
    case INVALID:
        break;
    case LOGIN:
        packet = new Packet00Login(data);
        handleLogin((Packet00Login) packet, address, port);
        break;
    case DISCONNECT:
        packet = new Packet01Disconnect(data);
        System.out.println("[" + address.getHostAddress() + ":" + port + "] "
                + ((Packet01Disconnect) packet).getUsername() + " has left the world...");
        game.level.removePlayerMP(((Packet01Disconnect) packet).getUsername());
        break;
    case MOVE:
        packet = new Packet02Move(data);
        handleMove((Packet02Move) packet);
    }
}

public void sendData(byte[] data) {
    //if (!game.isApplet) {
        DatagramPacket packet = new DatagramPacket(data, data.length, ipAddress, 3333);
        try {
            socket.send(packet);
        } catch (IOException e) {
            e.printStackTrace();
        }
   //}
}

private void handleLogin(Packet00Login packet, InetAddress address, int port) {
    System.out.println("[" + address.getHostAddress() + ":" + port + "] " + packet.getUsername()
            + " has joined the game...");
    PlayerMP player = new PlayerMP(game.level, packet.getX(), packet.getY(), packet.getUsername(), address, port);
    game.level.addEntity(player);
}

private void handleMove(Packet02Move packet) {
    this.game.level.movePlayer(packet.getUsername(), packet.getX(), packet.getY(), packet.getNumSteps(),
            packet.isMoving(), packet.getMovingDir());
}

}

GameServer.java

package fraccas.java2dgame.net;


public class GameServer extends Thread {

private DatagramSocket socket;
private Game game;
private List<PlayerMP> connectedPlayers = new ArrayList<PlayerMP>();

public GameServer(Game game) {
    this.game = game;
    try {
        this.socket = new DatagramSocket(3333);
    } catch (SocketException e) {
        e.printStackTrace();
    }
}

public void run() {
    while (true) {
        byte[] data = new byte[1024];
        DatagramPacket packet = new DatagramPacket(data, data.length);
        try {
            socket.receive(packet);
        } catch (IOException e) {
            e.printStackTrace();
        }
        this.parsePacket(packet.getData(), packet.getAddress(), packet.getPort());
    }
}

private void parsePacket(byte[] data, InetAddress address, int port) {
    String message = new String(data).trim();
    PacketTypes type = Packet.lookupPacket(message.substring(0, 2));
    Packet packet = null;
    switch (type) {
    default:
    case INVALID:
        break;
    case LOGIN:
        packet = new Packet00Login(data);
        System.out.println("[" + address.getHostAddress() + ":" + port + "] "
                + ((Packet00Login) packet).getUsername() + " has connected...");
        PlayerMP player = new PlayerMP(game.level, 100, 100, ((Packet00Login) packet).getUsername(), address, port);
        this.addConnection(player, (Packet00Login) packet);
        break;
    case DISCONNECT:
        packet = new Packet01Disconnect(data);
        System.out.println("[" + address.getHostAddress() + ":" + port + "] "
                + ((Packet01Disconnect) packet).getUsername() + " has left...");
        this.removeConnection((Packet01Disconnect) packet);
        break;
    case MOVE:
        packet = new Packet02Move(data);
        this.handleMove(((Packet02Move) packet));
    }
}

public void addConnection(PlayerMP player, Packet00Login packet) {
    boolean alreadyConnected = false;
    for (PlayerMP p : this.connectedPlayers) {
        if (player.getUsername().equalsIgnoreCase(p.getUsername())) {
            if (p.ipAddress == null) {
                p.ipAddress = player.ipAddress;
            }
            if (p.port == -1) {
                p.port = player.port;
            }
            alreadyConnected = true;
        } else {
            // relay to the current connected player that there is a new
            // player
            sendData(packet.getData(), p.ipAddress, p.port);

            // relay to the new player that the currently connect player
            // exists
            //packet = new Packet00Login(p.getUsername(), p.x, p.y);
            Packet00Login packetNew = new Packet00Login(p.getUsername(), p.x, p.y);
            sendData(packetNew.getData(), player.ipAddress, player.port);
        }
    }
    if (!alreadyConnected) {
        this.connectedPlayers.add(player);
    }
}

public void removeConnection(Packet01Disconnect packet) {
    this.connectedPlayers.remove(getPlayerMPIndex(packet.getUsername()));
    packet.writeData(this);
}

public PlayerMP getPlayerMP(String username) {
    for (PlayerMP player : this.connectedPlayers) {
        if (player.getUsername().equals(username)) {
            return player;
        }
    }
    return null;
}

public int getPlayerMPIndex(String username) {
    int index = 0;
    for (PlayerMP player : this.connectedPlayers) {
        if (player.getUsername().equals(username)) {
            break;
        }
        index++;
    }
    return index;
}

public void sendData(byte[] data, InetAddress ipAddress, int port) {
    //if (!game.isApplet) {

        DatagramPacket packet = new DatagramPacket(data, data.length, ipAddress, port);
        try {
            this.socket.send(packet);
        } catch (IOException e) {
            e.printStackTrace();
        }
    //}
}

public void sendDataToAllClients(byte[] data) {
    for (PlayerMP p : connectedPlayers) {
        sendData(data, p.ipAddress, p.port);
    }
}

private void handleMove(Packet02Move packet) {
    if (getPlayerMP(packet.getUsername()) != null) {
        int index = getPlayerMPIndex(packet.getUsername());
        PlayerMP player = this.connectedPlayers.get(index);
        player.x = packet.getX();
        player.y = packet.getY();
        player.setMoving(packet.isMoving());
        player.setMovingDir(packet.getMovingDir());
        player.setNumSteps(packet.getNumSteps());
        packet.writeData(this);
    }
}

该小程序目前在控制台中没有任何错误。 它只是不发送/接收数据。

http://critterisland.bugs3.com/public_html/index.html（Applet链接） http://gyazo.com/a91401545b1a741f2b9fc86471bd5762 （Applet的图片）

感谢您的时间，Fraccas

Answer 1

问题是您使用的是Web主机，该主机只能向用户提供文件，而不是实际能够运行您创建的软件。

要以所需的方式独立运行软件，最简单的选择是租用适合用户的虚拟专用服务器（VPS）。 但是，您将需要能够在VPS上进行一些基本配置（例如安装Java），然后将服务器作为控制台应用程序运行。

无需更改太多代码即可使其工作。 通过添加仅启动服务器的命令行参数（即“ -server”），可以为服务器和客户端使用相同的jar文件。 然后，从服务器计算机/ VPS运行“ java -jar CritterIslandTest.jar -server”启动服务器，然后仅启动服务器并处理通信。 如果找不到命令行参数，则可以继续使用GUI逻辑。