WsSession.java 文件源码

@SuppressWarnings("unchecked")
private void doAddMessageHandler(Class<?> target, MessageHandler listener) {
    checkState();

    // Message handlers that require decoders may map to text messages,
    // binary messages, both or neither.

    // The frame processing code expects binary message handlers to
    // accept ByteBuffer

    // Use the POJO message handler wrappers as they are designed to wrap
    // arbitrary objects with MessageHandlers and can wrap MessageHandlers
    // just as easily.

    Set<MessageHandlerResult> mhResults = Util.getMessageHandlers(target, listener, endpointConfig, this);

    for (MessageHandlerResult mhResult : mhResults) {
        switch (mhResult.getType()) {
        case TEXT: {
            if (textMessageHandler != null) {
                throw new IllegalStateException(sm.getString("wsSession.duplicateHandlerText"));
            }
            textMessageHandler = mhResult.getHandler();
            break;
        }
        case BINARY: {
            if (binaryMessageHandler != null) {
                throw new IllegalStateException(sm.getString("wsSession.duplicateHandlerBinary"));
            }
            binaryMessageHandler = mhResult.getHandler();
            break;
        }
        case PONG: {
            if (pongMessageHandler != null) {
                throw new IllegalStateException(sm.getString("wsSession.duplicateHandlerPong"));
            }
            MessageHandler handler = mhResult.getHandler();
            if (handler instanceof MessageHandler.Whole<?>) {
                pongMessageHandler = (MessageHandler.Whole<PongMessage>) handler;
            } else {
                throw new IllegalStateException(sm.getString("wsSession.invalidHandlerTypePong"));
            }

            break;
        }
        default: {
            throw new IllegalArgumentException(
                    sm.getString("wsSession.unknownHandlerType", listener, mhResult.getType()));
        }
        }
    }
}