javax.websocket 클라이언트 간단한 예제

javax.websocket 클라이언트 간단한 예제

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누군가가 사용하는 websocket 클라이언트의 매우 간단한 예제를 제공해 주 javax.websocket시겠습니까?

websocket (ws : //socket.example.com : 1234)에 연결하여 메시지를 보내고 (채널 추가) 메시지를 듣고 싶습니다. 모든 메시지 (전송 및 수신)는 JSON 형식입니다.

그리고 btw는이 라이브러리가 간단한 웹 소켓 통신에 가장 적합합니까?

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javax.websocket여기에서 사용하는 좋은 예를 찾았 습니다.

http://www.programmingforliving.com/2013/08/jsr-356-java-api-for-websocket-client-api.html

다음은 위에 링크 된 예제를 기반으로 한 코드입니다.

TestApp.java:

package testapp;

import java.net.URI;
import java.net.URISyntaxException;

public class TestApp {

    public static void main(String[] args) {
        try {
            // open websocket
            final WebsocketClientEndpoint clientEndPoint = new WebsocketClientEndpoint(new URI("wss://real.okcoin.cn:10440/websocket/okcoinapi"));

            // add listener
            clientEndPoint.addMessageHandler(new WebsocketClientEndpoint.MessageHandler() {
                public void handleMessage(String message) {
                    System.out.println(message);
                }
            });

            // send message to websocket
            clientEndPoint.sendMessage("{'event':'addChannel','channel':'ok_btccny_ticker'}");

            // wait 5 seconds for messages from websocket
            Thread.sleep(5000);

        } catch (InterruptedException ex) {
            System.err.println("InterruptedException exception: " + ex.getMessage());
        } catch (URISyntaxException ex) {
            System.err.println("URISyntaxException exception: " + ex.getMessage());
        }
    }
}

WebsocketClientEndpoint.java:

package testapp;

import java.net.URI;
import javax.websocket.ClientEndpoint;
import javax.websocket.CloseReason;
import javax.websocket.ContainerProvider;
import javax.websocket.OnClose;
import javax.websocket.OnMessage;
import javax.websocket.OnOpen;
import javax.websocket.Session;
import javax.websocket.WebSocketContainer;

/**
 * ChatServer Client
 *
 * @author Jiji_Sasidharan
 */
@ClientEndpoint
public class WebsocketClientEndpoint {

    Session userSession = null;
    private MessageHandler messageHandler;

    public WebsocketClientEndpoint(URI endpointURI) {
        try {
            WebSocketContainer container = ContainerProvider.getWebSocketContainer();
            container.connectToServer(this, endpointURI);
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    /**
     * Callback hook for Connection open events.
     *
     * @param userSession the userSession which is opened.
     */
    @OnOpen
    public void onOpen(Session userSession) {
        System.out.println("opening websocket");
        this.userSession = userSession;
    }

    /**
     * Callback hook for Connection close events.
     *
     * @param userSession the userSession which is getting closed.
     * @param reason the reason for connection close
     */
    @OnClose
    public void onClose(Session userSession, CloseReason reason) {
        System.out.println("closing websocket");
        this.userSession = null;
    }

    /**
     * Callback hook for Message Events. This method will be invoked when a client send a message.
     *
     * @param message The text message
     */
    @OnMessage
    public void onMessage(String message) {
        if (this.messageHandler != null) {
            this.messageHandler.handleMessage(message);
        }
    }

    /**
     * register message handler
     *
     * @param msgHandler
     */
    public void addMessageHandler(MessageHandler msgHandler) {
        this.messageHandler = msgHandler;
    }

    /**
     * Send a message.
     *
     * @param message
     */
    public void sendMessage(String message) {
        this.userSession.getAsyncRemote().sendText(message);
    }

    /**
     * Message handler.
     *
     * @author Jiji_Sasidharan
     */
    public static interface MessageHandler {

        public void handleMessage(String message);
    }
}

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TooTallNate에는 간단한 클라이언트 측 https://github.com/TooTallNate/Java-WebSocket이 있습니다.

dist 폴더의 java_websocket.jar을 프로젝트에 추가하기 만하면됩니다.

 import org.java_websocket.client.WebSocketClient;
 import org.java_websocket.drafts.Draft_10;
 import org.java_websocket.handshake.ServerHandshake;
 import org.json.JSONException;
 import org.json.JSONObject;

  WebSocketClient mWs = new WebSocketClient( new URI( "ws://socket.example.com:1234" ), new Draft_10() )
{
                    @Override
                    public void onMessage( String message ) {
                     JSONObject obj = new JSONObject(message);
                     String channel = obj.getString("channel");
                    }

                    @Override
                    public void onOpen( ServerHandshake handshake ) {
                        System.out.println( "opened connection" );
                    }

                    @Override
                    public void onClose( int code, String reason, boolean remote ) {
                        System.out.println( "closed connection" );
                    }

                    @Override
                    public void onError( Exception ex ) {
                        ex.printStackTrace();
                    }

                };
 //open websocket
 mWs.connect();
 JSONObject obj = new JSONObject();
 obj.put("event", "addChannel");
 obj.put("channel", "ok_btccny_ticker");
 String message = obj.toString();
 //send message
 mWs.send(message);

// 그리고 websocket을 닫습니다.

 mWs.close();

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Arun Gupta의이 Java EE 7 예제를 살펴보십시오.

I forked it on github.

Main

/**
 * @author Arun Gupta
 */
public class Client {

    final static CountDownLatch messageLatch = new CountDownLatch(1);

    public static void main(String[] args) {
        try {
            WebSocketContainer container = ContainerProvider.getWebSocketContainer();
            String uri = "ws://echo.websocket.org:80/";
            System.out.println("Connecting to " + uri);
            container.connectToServer(MyClientEndpoint.class, URI.create(uri));
            messageLatch.await(100, TimeUnit.SECONDS);
        } catch (DeploymentException | InterruptedException | IOException ex) {
            Logger.getLogger(Client.class.getName()).log(Level.SEVERE, null, ex);
        }
    }
}

ClientEndpoint

/**
 * @author Arun Gupta
 */
@ClientEndpoint
public class MyClientEndpoint {
    @OnOpen
    public void onOpen(Session session) {
        System.out.println("Connected to endpoint: " + session.getBasicRemote());
        try {
            String name = "Duke";
            System.out.println("Sending message to endpoint: " + name);
            session.getBasicRemote().sendText(name);
        } catch (IOException ex) {
            Logger.getLogger(MyClientEndpoint.class.getName()).log(Level.SEVERE, null, ex);
        }
    }

    @OnMessage
    public void processMessage(String message) {
        System.out.println("Received message in client: " + message);
        Client.messageLatch.countDown();
    }

    @OnError
    public void processError(Throwable t) {
        t.printStackTrace();
    }
}

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Here is one simple example.. you can download and test it http://www.pretechsol.com/2014/12/java-ee-websocket-simple-example.html

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Use this library org.java_websocket

First thing you should import that library in build.gradle

repositories {
 mavenCentral()
 }

then add the implementation in dependency{}

implementation "org.java-websocket:Java-WebSocket:1.3.0"

Then you can use this code

In your activity declare object for Websocketclient like

private WebSocketClient mWebSocketClient;

then add this method for callback

 private void ConnectToWebSocket() {
URI uri;
try {
    uri = new URI("ws://your web socket url");
} catch (URISyntaxException e) {
    e.printStackTrace();
    return;
}

mWebSocketClient = new WebSocketClient(uri) {
    @Override
    public void onOpen(ServerHandshake serverHandshake) {
        Log.i("Websocket", "Opened");
        mWebSocketClient.send("Hello from " + Build.MANUFACTURER + " " + Build.MODEL);
    }

    @Override
    public void onMessage(String s) {
        final String message = s;
        runOnUiThread(new Runnable() {
            @Override
            public void run() {
                TextView textView = (TextView)findViewById(R.id.edittext_chatbox);
                textView.setText(textView.getText() + "\n" + message);
            }
        });
    }

    @Override
    public void onClose(int i, String s, boolean b) {
        Log.i("Websocket", "Closed " + s);
    }

    @Override
    public void onError(Exception e) {
        Log.i("Websocket", "Error " + e.getMessage());
    }
};
mWebSocketClient.connect();

}

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I have Spring 4.2 in my project and many SockJS Stomp implementations usually work well with Spring Boot implementations. This implementation from Baeldung worked(for me without changing from Spring 4.2 to 5). After Using the dependencies mentioned in his blog, it still gave me ClassNotFoundError. I added the below dependency to fix it.

<dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-core</artifactId>
        <version>4.2.3.RELEASE</version>
    </dependency>

참고URL : https://stackoverflow.com/questions/26452903/javax-websocket-client-simple-example