我有一个新问题，我无法解决最后一个问题： Multicast : using joinGroup on a multicast socket (java/android) packet isn't received
所以我尝试了另一种方式。 我在我的计算机和客户端上启动服务器作为我的androiddevice上的应用程序。但是，当我试图连接到我的计算机时，我收到错误：
java.net.ConnectException：无法连接到/192.168.137.1（端口54321）：连接失败：ENETUNREACH
但我确认我可以从我的计算机ping到设备，并在我的防火墙关闭时反转。我不明白为什么它可以通过ping操作使用套接字。
我的代码：
服务器
public class Server implements Runnable
{
private final ServerSocket serverSocket;
public Server() throws IOException {
//serverSocket = new ServerSocket(Constant.SERVER_PORT);
serverSocket = new ServerSocket(Constant.SERVER_PORT, 1000, InetAddress.getLocalHost());
}
public static void main(String[] args) throws IOException {
new Server().open();
}
private void open()
{
Socket client;
BufferedReader in;
PrintWriter out;
while (true) {
try {
// TODO: 25/03/2017 Threaded Service
client = serverSocket.accept();
System.out.println("Client accepted");
in = new BufferedReader(new InputStreamReader(client.getInputStream()));
out = new PrintWriter(client.getOutputStream());
Thread.sleep(200);
out.println("CONNECTED");
out.flush();
} catch (Exception e) {
e.printStackTrace();
}
}
}
@Override
public void run() {
open();
Scanner sc = new Scanner(System.in);
sc.next();
while(true);
}
我的活动中连接到服务器的线程：
public class Home extends AppCompatActivity {
private HandlerConnectionRunnable handlerConnectionMsg;
private HandlerNetwork handlerNetwork;
private boolean connectionOver = false;
private InetAddress hotspotIP;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home);
handlerConnectionMsg = new HandlerConnectionRunnable();
new Thread(new ConnectionRunnable()).start();
}
public void sendData(View view)
{
if (!connectionOver)
return;
}
@Override
protected void onDestroy() {
super.onDestroy();
}
public void getFirstMessage()
{
new Thread(new FirstMessage()).start();
}
private class ConnectionRunnable implements Runnable
{
private static final String CONNECTION_MESSAGE_KEY = "connection_message";
private static final String CURRENT_AP = "current_ap";
private static final int ACTIVATING_WIFI = 0;
private static final int CONNECTION_AP = 1;
private static final int CONNECTED = 2;
private static final int CONNECTION_ERROR = 3;
private Message msg;
@Override
public void run()
{
msg = handlerConnectionMsg.obtainMessage();
Bundle b = new Bundle();
// Get the wifi manager
WifiManager wifiManager = (WifiManager) getApplicationContext().getSystemService(Context.WIFI_SERVICE);
// Enable the wifi
boolean wasEnabled = wifiManager.isWifiEnabled();
msg = handlerConnectionMsg.obtainMessage();
b = new Bundle();
b.putInt("connection_message", ACTIVATING_WIFI);
msg.setData(b);
handlerConnectionMsg.sendMessage(msg);
wifiManager.setWifiEnabled(true);
// Wait for the connection
while(!wifiManager.isWifiEnabled());
boolean ret = true;
// Connect to the access point and disable the connection to others
if (wifiManager.isWifiEnabled() && wifiManager.startScan())
{
msg = handlerConnectionMsg.obtainMessage();
b = new Bundle();
b.putInt("connection_message", CONNECTION_AP);
msg.setData(b);
handlerConnectionMsg.sendMessage(msg);
ret = connectToAP(wifiManager, "trainee_hotspot_test", "d0nt3nt3rThis");
//ret = connectToAP(wifiManager, "trainee_test", "12345678");
}
if (!ret)
{
msg = handlerConnectionMsg.obtainMessage();
b = new Bundle();
b.putInt("connection_message", CONNECTION_ERROR);
msg.setData(b);
handlerConnectionMsg.sendMessage(msg);
return;
}
/*
WifiManager.MulticastLock multicastLock = wifiManager.createMulticastLock("mydebuginfo");
//multicastLock.setReferenceCounted(true);
multicastLock.acquire();
*/
//WifiInfo wifiInfo = wifiManager.getConnectionInfo();
//int ipAddress = wifiInfo.getIpAddress();
int ipAddress = wifiManager.getDhcpInfo().serverAddress;
try {
hotspotIP = InetAddress.getByName(convertToIp(ipAddress));
//System.out.println(hotspotIP.getHostAddress());
} catch (UnknownHostException e) {
e.printStackTrace();
}
msg = handlerConnectionMsg.obtainMessage();
b = new Bundle();
// Valid connection
b.putInt("connection_message", CONNECTED);
b.putString("current_ap", wifiManager.getConnectionInfo().getSSID());
msg.setData(b);
handlerConnectionMsg.sendMessage(msg);
}
private String convertToIp(int ipAddress) throws UnknownHostException {
byte[] address = { (byte)(0xff & ipAddress),
(byte)(0xff & (ipAddress >> 8)),
(byte)(0xff & (ipAddress >> 16)),
(byte)(0xff & (ipAddress >> 24)) };
return InetAddress.getByAddress(address).getHostAddress();
}
private boolean connectToAP(WifiManager wifi, String name, String pass)
{
// Create a new wifiConfiguration object
WifiConfiguration wifiConfig = new WifiConfiguration();
// Add informations to it
wifiConfig.SSID = String.format("\"%s\"", name);
wifiConfig.preSharedKey = String.format("\"%s\"", pass);
// We add this configuration to the wifi manager and get the id
int netId = wifi.addNetwork(wifiConfig);
// Disconnect from the current AP
wifi.disconnect();
// Enable the hotspot with given SSID if it exists
boolean status = wifi.enableNetwork(netId, true);
wifi.reconnect();
return status;
}
}
private class HandlerConnectionRunnable extends Handler
{
@Override
public void handleMessage(Message msg) {
super.handleMessage(msg);
Home.this.connectionOver = true;
Bundle b = msg.getData();
int connectionMsg = b.getInt(ConnectionRunnable.CONNECTION_MESSAGE_KEY);
switch (connectionMsg)
{
case ConnectionRunnable.ACTIVATING_WIFI:
Toast.makeText(Home.this, "The wifi will be activated", Toast.LENGTH_SHORT).show();
break;
case ConnectionRunnable.CONNECTION_AP:
Toast.makeText(Home.this, "The connection to the current access point will be disabled", Toast.LENGTH_LONG).show();
break;
case ConnectionRunnable.CONNECTION_ERROR:
Toast.makeText(Home.this, "The connection wasn't possible", Toast.LENGTH_SHORT).show();
break;
case ConnectionRunnable.CONNECTED:
Toast.makeText(Home.this, "Connected to : " + b.getString(ConnectionRunnable.CURRENT_AP), Toast.LENGTH_SHORT).show();
getFirstMessage();
break;
}
}
}
private class HandlerNetwork extends Handler
{
@Override
public void handleMessage(Message msg) {
super.handleMessage(msg);
Toast.makeText(Home.this, msg.getData().getString("NETWORK"), Toast.LENGTH_LONG).show();
}
}
private class FirstMessage implements Runnable
{
@Override
public void run() {
Socket socket = null;
socket = new Socket();
try {
//socket = new Socket(hotspotIP, Constant.SERVER_PORT);
socket = new Socket();
socket.connect(new InetSocketAddress(hotspotIP, Constant.SERVER_PORT));
BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
PrintWriter out = new PrintWriter(socket.getOutputStream());
String read = in.readLine();
Message msg = handlerNetwork.obtainMessage();
Bundle b = new Bundle();
b.putString("NETWORK", "CONNECTED");
msg.setData(b);
handlerNetwork.sendMessage(msg);
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
感谢大家的回复
度过美好的一天
更新
我忘了说手机和电脑在同一个网络上，因为手机已连接到我的电脑热点。
更新2
我把整个课程都放在了客户端上，以免忘记代码的任何重要部分。
更新3 在使用Ray的链接后，我获得了：
显示名称：ip6tnl0 名称：ip6tnl0 显示名称：wlan0 姓名：wlan0 显示名称：tunl0 名称：tunl0 显示名称：sit0 姓名：sit0 显示名称：p2p0 名称：p2p0 InetAddress：/ fe80 :: 73：8dff：fefa：c4a3％p2p0％11 显示名称：ifb0 名称：ifb0 显示名称：ifb1 名称：ifb1 显示名称：lo InetAddress：/ :: 1％1％1 InetAddress：/127.0.0.1 显示名称：ccmni2 名称：ccmni2 0显示名称：ccmni0 名称：ccmni0 显示名称：ccmni1 名称：ccmni1