这可能是显而易见的,但我是新来这个范例。 我创建了一个Jetty服务器并注册我的WebSocket类,如下所示:
Server server = new Server(8080);
WebSocketHandler wsHandler = new WebSocketHandler()
{
@Override
public void configure(WebSocketServletFactory factory)
{
factory.register(MyEchoSocket.class);
}
};
server.setHandler(wsHandler);
网页套接字接收消息细。 我想也可以从服务器将邮件发送,而无需首先收到一则由客户端。 如何访问的连接打开时所创建的MyEchoSocket实例? 或者更一般地说,我怎么在插座上发送消息在MyEchoSocket的onText方法之外?
两种常见的技术,在一个超级简单的聊天室的概念这里介绍。
选项#1:拥有的WebSocket其状态报告给中央位置
@WebSocket
public class ChatSocket {
public Session session;
@OnWebSocketConnect
public void onConnect(Session session) {
this.session = session;
ChatRoom.getInstance().join(this);
}
@OnWebSocketMessage
public void onText(String message) {
ChatRoom.getInstance().writeAllMembers("Hello all");
}
@OnWebSocketClose
public void onClose(int statusCode, String reason) {
ChatRoom.getInstance().part(this);
}
}
public class ChatRoom {
private static final ChatRoom INSTANCE = new ChatRoom();
public static ChatRoom getInstance()
{
return INSTANCE;
}
private List<ChatSocket> members = new ArrayList<>();
public void join(ChatSocket socket)
{
members.add(socket);
}
public void part(ChatSocket socket)
{
members.remove(socket);
}
public void writeAllMembers(String message)
{
for(ChatSocket member: members)
{
member.session.getRemote().sendStringByFuture(message);
}
}
public void writeSpecificMember(String memberName, String message)
{
ChatSocket member = findMemberByName(memberName);
member.session.getRemote().sendStringByFuture(message);
}
public ChatSocket findMemberByName(String memberName)
{
// left as exercise to reader
}
}
然后,只需使用中央位置谈谈你所选择的的WebSockets。
ChatRoom.getInstance().writeSpecificMember("alex", "Hello");
// or
ChatRoom.getInstance().writeAllMembers("Hello all");
选项2:有没有WebSocket的手动与WebSocketCreator创建
@WebSocket
public class ChatSocket {
public ChatRoom chatroom;
public ChatSocket(ChatRoom chatroom)
{
this.chatroom = chatroom;
}
@OnWebSocketConnect
public void onConnect(Session session) {
chatroom.join(this);
}
@OnWebSocketMessage
public void onText(String message) {
chatroom.writeAllMembers(message);
}
@OnWebSocketClose
public void onClose(int statusCode, String reason) {
chatroom.part(this);
}
}
public class ChatCreator implements WebSocketCreator
{
private ChatRoom chatroom;
public ChatCreator(ChatRoom chatroom)
{
this.chatroom = chatroom;
}
public Object createWebSocket(UpgradeRequest request,
UpgradeResponse response)
{
// We want to create the Chat Socket and associate
// it with our chatroom implementation
return new ChatSocket(chatroom);
}
}
public class ChatHandler extends WebSocketHandler
{
private ChatRoom chatroom = new ChatRoom();
@Override
public void configure(WebSocketServletFactory factory)
{
factory.setCreator(new ChatCreator(chatroom));
}
}
在这一点上,你可以使用相同的技术上面跟你选择的的WebSockets。