public class SocketActivity extends ListActivity implements Client.MsgListener {
public static final int PORT = 11232;
public static final String HOST = "192.168.1.187"; //此 IP 为内网 IP ，所有只有在同一局域网下才能通讯(连接同一WIFI即可)
private TextView msgTextView;
private EditText editText;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
String[] array = {"开启服务器",
"开启客户端",
"客户端发消息",
"客户端下线"};
setListAdapter(new ArrayAdapter<>(this, android.R.layout.simple_list_item_1, Arrays.asList(array)));
editText = new EditText(this);
getListView().addFooterView(editText);
msgTextView = new TextView(this);
getListView().addFooterView(msgTextView);
}
@Override
protected void onListItemClick(ListView l, View v, int position, long id) {
switch (position) {
case 0:
Server.SINGLETON.startServer(PORT);
break;
case 1:
Client.SINGLETON.startClient(HOST, PORT);
Client.SINGLETON.setListener(this);
break;
case 2:
Client.SINGLETON.sendMsg(editText.getText().toString());
break;
case 3:
Client.SINGLETON.exit();
break;
default:
break;
}
}
private SpannableString getSpannableString(String string, int color) {
SpannableString mSpannableString = new SpannableString(string);
ForegroundColorSpan colorSpan = new ForegroundColorSpan(color);
mSpannableString.setSpan(colorSpan, 0, mSpannableString.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
return mSpannableString;
}
@Override
public void onReveiveMsg(String message) {
runOnUiThread(() -> msgTextView.append(getSpannableString(message + "\n", Color.BLUE)));
}
@Override
public void onSendMsg(String message) {
runOnUiThread(() -> {
String text = Client.SINGLETON.getName() + " : " + editText.getText().toString() + "\n";
msgTextView.append(getSpannableString(text, Color.RED));
});
}
}

public enum Server {
SINGLETON;
public static final int MAX_TEXT_SIZE = 1024;
public static final String CLIENT_EXIT_CMD = "拜拜";
public static final String CHARSET = "GBK";
private Set socketSet;
private boolean serverExit = false;
private ServerSocket server;//服务器对象
Server() {
socketSet = new HashSet<>();//用户集合
}
public void startServer(int port) {
if (server != null && !server.isClosed()) {
System.out.println("服务器已开启，不需要重复开启");
} else {
new Thread(() -> {
try {
server = new ServerSocket(port);
} catch (IOException e) {
e.printStackTrace();
System.out.println("服务器启动失败");
return;
}
System.out.println("服务器启动成功");
//循环监听
while (!serverExit) {
try {
Socket socket = server.accept();//获取连接过来的客户端对象。阻塞方法
socketSet.add(socket);
sendUserMsg(socket, getName(socket) + " 上线了, 当前 " + socketSet.size() + " 人在线");
listenerUserMsg(socket); //监听客户端发送的消息，并转发给其他用户
} catch (IOException e) {//用户下线
e.printStackTrace();
}
}
System.out.println("服务器已关闭");
}).start();
}
}
private void listenerUserMsg(Socket socket) {
new Thread(() -> {
try {
byte[] bytes = new byte[MAX_TEXT_SIZE];
int count;
boolean clinetExit = false;
while (!serverExit && !clinetExit && !socket.isClosed() && (count = socket.getInputStream().read(bytes)) != -1) {
String text = new String(bytes, 0, count, CHARSET);
System.out.println("服务器已收到【" + getName(socket) + "】发送的信息【" + text + "】");
clinetExit = CLIENT_EXIT_CMD.equals(text);
sendUserMsg(socket, getName(socket) + " : " + text);
}
} catch (IOException e) {//关闭与此用户相关的流
e.printStackTrace();
System.out.println(getName(socket) + " 异常掉线");
} finally {
if (socket != null) {
try {
socket.close();
} catch (IOException e) {
e.printStackTrace();
}
socketSet.remove(socket);
sendUserMsg(socket, getName(socket) + " 下线了, 当前 " + socketSet.size() + " 人在线");
}
}
}).start();
}
private void sendUserMsg(Socket socket, String text) {
for (Socket otherSocket : socketSet) {//遍历所有的在线用户
if (otherSocket != null && !otherSocket.isClosed() && !otherSocket.equals(socket)) {
try {
OutputStream outputStream = otherSocket.getOutputStream();//获取相应的输出流，把信息发送过去
outputStream.write(text.getBytes(CHARSET));
outputStream.flush();
System.out.println("服务器已转发信息【" + text + "】给【" + getName(otherSocket) + "】");
} catch (IOException e) {
e.printStackTrace();
System.out.println(getName(socket) + " 异常");
}
}
}
}
private String getName(Socket socket) {
return "用户" + socket.getInetAddress().getHostAddress() + "_" + socket.getPort();
}
}

public enum Client {
SINGLETON;
Client() {
}
public static final int MAX_TEXT_SIZE = 1024;
public static final String CLIENT_EXIT_CMD = "拜拜";
public static final String CHARSET = "GBK";
private boolean exit = false;
private Socket socket;
private MsgListener listener;
public void startClient(String host, int port) {
if (socket != null && !socket.isClosed()) {
System.out.println("客户端已开启，不需要重复开启");
} else {
new Thread(() -> {
try {
socket = new Socket(host, port);//创建客户端对象
listenerUserMsg(); //监听消息
System.out.println("客户端已开启成功");
} catch (IOException e) {
e.printStackTrace();
System.out.println("客户端已开启失败");
}
}).start();
}
}
private void listenerUserMsg() {
new Thread(() -> {
try {
byte[] bytes = new byte[MAX_TEXT_SIZE];
int count;
while (!exit && socket != null && !socket.isClosed() && (count = socket.getInputStream().read(bytes)) != -1) {
String text = new String(bytes, 0, count, CHARSET);
System.out.println(getName() + " 收到信息【" + text + "】");
if (listener != null) {
listener.onReveiveMsg(text);
}
}
} catch (IOException e) {
e.printStackTrace();
}
}).start();
}
public void sendMsg(String text) {
new Thread(() -> {
if (socket != null && !socket.isClosed()) {
try {
socket.getOutputStream().write(text.getBytes(CHARSET));//获取socket流中的输出流将指定的数据写出去
if (listener != null) {
listener.onSendMsg(text);
}
} catch (IOException e) {
e.printStackTrace();
}
}
}).start();
}
public void exit() {
new Thread(() -> {
exit = true;
if (socket != null && !socket.isClosed()) {
try {
socket.getOutputStream().write(CLIENT_EXIT_CMD.getBytes(CHARSET));
socket.close();
System.out.println("客户端下线成功");
} catch (IOException e) {
e.printStackTrace();
System.out.println("客户端下线异常");
}
} else {
System.out.println("客户端已下线，不需要重复下线");
}
}).start();
}
public String getName() {
return "用户" + socket.getInetAddress().getHostAddress() + "_" + socket.getPort();
}
public void setListener(MsgListener listener) {
this.listener = listener;
}
public interface MsgListener {
void onReveiveMsg(String message);
void onSendMsg(String message);
}
}