JS library to add whiteboard functionality. Allows draw lines and text, drag them. Can synchronise content using websockets. See the demo version at http://bay73.github.io/whiteboard/

How to use:

1. Add js, css and inage files from bin folder to you project.
2. Add html-elemment which will contain whiteboard
3. Create whiteboard with using call bay.whiteboard.Create()
4. Render created whiteboard to the html-element using whiteboard.render

To use synchronisation create websocket chat-server. Below is a sample code based on org.apache.catalina.websocket.WebSocketServlet Link websocket address to whiteboard: whiteboard.linkWebSocket('ws://host:port/path');

Sample websocket server:

public class WhiteboardWebSocketServlet extends WebSocketServlet { private static final long serialVersionUID = 2L; // Set of connected clients private final Set connections = new CopyOnWriteArraySet(); @Override protected StreamInbound createWebSocketInbound(String subProtocol, HttpServletRequest request) { return new WBMessageInbound(); } private final class WBMessageInbound extends MessageInbound { @Override protected void onOpen(WsOutbound outbound) { connections.add(this); } @Override protected void onClose(int status) { connections.remove(this); } @Override protected void onBinaryMessage(ByteBuffer message) throws IOException { throw new UnsupportedOperationException("Binary message not supported."); } @Override protected void onTextMessage(CharBuffer message) throws IOException { // translate the message to all other clients for (WBMessageInbound connection : connections) { try { if (connection != this) connection.getWsOutbound().writeTextMessage(message); } catch (IOException ignore) { } } } } }