org.springframework.web.socket.adapter.standard.StandardWebSocketHandlerAdapter.java Source code

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Here is the source code for org.springframework.web.socket.adapter.standard.StandardWebSocketHandlerAdapter.java

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/*
 * Copyright 2002-2018 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.web.socket.adapter.standard;

import java.nio.ByteBuffer;
import javax.websocket.CloseReason;
import javax.websocket.Endpoint;
import javax.websocket.EndpointConfig;
import javax.websocket.MessageHandler;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import org.springframework.util.Assert;
import org.springframework.web.socket.BinaryMessage;
import org.springframework.web.socket.CloseStatus;
import org.springframework.web.socket.PongMessage;
import org.springframework.web.socket.TextMessage;
import org.springframework.web.socket.WebSocketHandler;
import org.springframework.web.socket.handler.ExceptionWebSocketHandlerDecorator;

/**
 * Adapts a {@link WebSocketHandler} to the standard WebSocket for Java API.
 *
 * @author Rossen Stoyanchev
 * @since 4.0
 */
public class StandardWebSocketHandlerAdapter extends Endpoint {

    private static final Log logger = LogFactory.getLog(StandardWebSocketHandlerAdapter.class);

    private final WebSocketHandler handler;

    private final StandardWebSocketSession wsSession;

    public StandardWebSocketHandlerAdapter(WebSocketHandler handler, StandardWebSocketSession wsSession) {
        Assert.notNull(handler, "WebSocketHandler must not be null");
        Assert.notNull(wsSession, "WebSocketSession must not be null");
        this.handler = handler;
        this.wsSession = wsSession;
    }

    @Override
    public void onOpen(final javax.websocket.Session session, EndpointConfig config) {
        this.wsSession.initializeNativeSession(session);

        if (this.handler.supportsPartialMessages()) {
            session.addMessageHandler(new MessageHandler.Partial<String>() {
                @Override
                public void onMessage(String message, boolean isLast) {
                    handleTextMessage(session, message, isLast);
                }
            });
            session.addMessageHandler(new MessageHandler.Partial<ByteBuffer>() {
                @Override
                public void onMessage(ByteBuffer message, boolean isLast) {
                    handleBinaryMessage(session, message, isLast);
                }
            });
        } else {
            session.addMessageHandler(new MessageHandler.Whole<String>() {
                @Override
                public void onMessage(String message) {
                    handleTextMessage(session, message, true);
                }
            });
            session.addMessageHandler(new MessageHandler.Whole<ByteBuffer>() {
                @Override
                public void onMessage(ByteBuffer message) {
                    handleBinaryMessage(session, message, true);
                }
            });
        }

        session.addMessageHandler(new MessageHandler.Whole<javax.websocket.PongMessage>() {
            @Override
            public void onMessage(javax.websocket.PongMessage message) {
                handlePongMessage(session, message.getApplicationData());
            }
        });

        try {
            this.handler.afterConnectionEstablished(this.wsSession);
        } catch (Throwable ex) {
            ExceptionWebSocketHandlerDecorator.tryCloseWithError(this.wsSession, ex, logger);
        }
    }

    private void handleTextMessage(javax.websocket.Session session, String payload, boolean isLast) {
        TextMessage textMessage = new TextMessage(payload, isLast);
        try {
            this.handler.handleMessage(this.wsSession, textMessage);
        } catch (Throwable ex) {
            ExceptionWebSocketHandlerDecorator.tryCloseWithError(this.wsSession, ex, logger);
        }
    }

    private void handleBinaryMessage(javax.websocket.Session session, ByteBuffer payload, boolean isLast) {
        BinaryMessage binaryMessage = new BinaryMessage(payload, isLast);
        try {
            this.handler.handleMessage(this.wsSession, binaryMessage);
        } catch (Throwable ex) {
            ExceptionWebSocketHandlerDecorator.tryCloseWithError(this.wsSession, ex, logger);
        }
    }

    private void handlePongMessage(javax.websocket.Session session, ByteBuffer payload) {
        PongMessage pongMessage = new PongMessage(payload);
        try {
            this.handler.handleMessage(this.wsSession, pongMessage);
        } catch (Throwable ex) {
            ExceptionWebSocketHandlerDecorator.tryCloseWithError(this.wsSession, ex, logger);
        }
    }

    @Override
    public void onClose(javax.websocket.Session session, CloseReason reason) {
        CloseStatus closeStatus = new CloseStatus(reason.getCloseCode().getCode(), reason.getReasonPhrase());
        try {
            this.handler.afterConnectionClosed(this.wsSession, closeStatus);
        } catch (Throwable ex) {
            if (logger.isWarnEnabled()) {
                logger.warn("Unhandled on-close exception for " + this.wsSession, ex);
            }
        }
    }

    @Override
    public void onError(javax.websocket.Session session, Throwable exception) {
        try {
            this.handler.handleTransportError(this.wsSession, exception);
        } catch (Throwable ex) {
            ExceptionWebSocketHandlerDecorator.tryCloseWithError(this.wsSession, ex, logger);
        }
    }

}