WebSocket.java

/*
 * Copyright (c) 2010-2019 Nathan Rajlich
 *
 *  Permission is hereby granted, free of charge, to any person
 *  obtaining a copy of this software and associated documentation
 *  files (the "Software"), to deal in the Software without
 *  restriction, including without limitation the rights to use,
 *  copy, modify, merge, publish, distribute, sublicense, and/or sell
 *  copies of the Software, and to permit persons to whom the
 *  Software is furnished to do so, subject to the following
 *  conditions:
 *
 *  The above copyright notice and this permission notice shall be
 *  included in all copies or substantial portions of the Software.
 *
 *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
 *  OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
 *  HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 *  WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 *  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 *  OTHER DEALINGS IN THE SOFTWARE.
 */

package org.java_websocket;

import java.net.InetSocketAddress;
import java.nio.ByteBuffer;
import java.util.Collection;

import org.java_websocket.drafts.Draft;
import org.java_websocket.enums.Opcode;
import org.java_websocket.enums.ReadyState;
import org.java_websocket.exceptions.WebsocketNotConnectedException;
import org.java_websocket.framing.Framedata;

import javax.net.ssl.SSLEngine;

public interface WebSocket {

	/**
	 * sends the closing handshake.
	 * may be send in response to an other handshake.
	 * @param code the closing code
	 * @param message the closing message
	 */
	void close( int code, String message );

	/**
	 * sends the closing handshake.
	 * may be send in response to an other handshake.
	 * @param code the closing code
	 */
	void close( int code );

	/** Convenience function which behaves like close(CloseFrame.NORMAL) */
	void close();

	/**
	 * This will close the connection immediately without a proper close handshake.
	 * The code and the message therefore won't be transfered over the wire also they will be forwarded to onClose/onWebsocketClose.
	 * @param code the closing code
	 * @param message the closing message
	 **/
	void closeConnection( int code, String message );

	/**
	 * Send Text data to the other end.
	 *
	 * @param text the text data to send
	 * @throws WebsocketNotConnectedException websocket is not yet connected
	 */
	void send( String text );

	/**
	 * Send Binary data (plain bytes) to the other end.
	 *
	 * @param bytes the binary data to send
	 * @throws IllegalArgumentException the data is null
	 * @throws WebsocketNotConnectedException websocket is not yet connected
	 */
	void send( ByteBuffer bytes );

	/**
	 * Send Binary data (plain bytes) to the other end.
	 *
	 * @param bytes the byte array to send
	 * @throws IllegalArgumentException the data is null
	 * @throws WebsocketNotConnectedException websocket is not yet connected
	 */
	void send( byte[] bytes );

	/**
	 * Send a frame to the other end
	 * @param framedata the frame to send to the other end
	 */
	void sendFrame( Framedata framedata );

	/**
	 * Send a collection of frames to the other end
	 * @param frames the frames to send to the other end
	 */
	void sendFrame( Collection<Framedata> frames );

	/**
	 * Send a ping to the other end
	 * @throws WebsocketNotConnectedException websocket is not yet connected
	 */
	void sendPing();

	/**
	 * Allows to send continuous/fragmented frames conveniently. <br>
	 * For more into on this frame type see http://tools.ietf.org/html/rfc6455#section-5.4<br>
	 * 
	 * If the first frame you send is also the last then it is not a fragmented frame and will received via onMessage instead of onFragmented even though it was send by this method.
	 * 
	 * @param op
	 *            This is only important for the first frame in the sequence. Opcode.TEXT, Opcode.BINARY are allowed.
	 * @param buffer
	 *            The buffer which contains the payload. It may have no bytes remaining.
	 * @param fin
	 *            true means the current frame is the last in the sequence.
	 **/
	void sendFragmentedFrame( Opcode op, ByteBuffer buffer, boolean fin );

	/**
	 * Checks if the websocket has buffered data
	 * @return has the websocket buffered data
	 */
	boolean hasBufferedData();

	/**
	 * Returns the address of the endpoint this socket is connected to, or{@code null} if it is unconnected.
	 *
	 * @return never returns null
	 */
	InetSocketAddress getRemoteSocketAddress();

	/**
	 * Returns the address of the endpoint this socket is bound to.
	 *
	 * @return never returns null
	 */
	InetSocketAddress getLocalSocketAddress();

	/**
	 * Is the websocket in the state OPEN
	 * @return state equals ReadyState.OPEN
	 */
	boolean isOpen();

	/**
	 * Is the websocket in the state CLOSING
	 * @return state equals ReadyState.CLOSING
	 */
	boolean isClosing();

	/**
	 * Returns true when no further frames may be submitted<br>
	 * This happens before the socket connection is closed.
	 * @return true when no further frames may be submitted
	 */
	boolean isFlushAndClose();

	/**
	 * Is the websocket in the state CLOSED
	 * @return state equals ReadyState.CLOSED
	 */
	boolean isClosed();

	/**
	 * Getter for the draft
	 * @return the used draft
	 */
	Draft getDraft();

	/**
	 * Retrieve the WebSocket 'ReadyState'.
	 * This represents the state of the connection.
	 * It returns a numerical value, as per W3C WebSockets specs.
	 * 
	 * @return Returns '0 = CONNECTING', '1 = OPEN', '2 = CLOSING' or '3 = CLOSED'
	 */
	ReadyState getReadyState();
	
	/**
	 * Returns the HTTP Request-URI as defined by http://tools.ietf.org/html/rfc2616#section-5.1.2<br>
	 * If the opening handshake has not yet happened it will return null.
	 * @return Returns the decoded path component of this URI.
	 **/
	String getResourceDescriptor();

	/**
	 * Setter for an attachment on the socket connection.
	 * The attachment may be of any type.
	 * 
	 * @param attachment The object to be attached to the user
	 * @param <T> The type of the attachment
	 * @since 1.3.7
	 **/
	<T> void setAttachment(T attachment);

	/**
	 * Getter for the connection attachment.
	 *
	 * @param <T> The type of the attachment
	 * @return Returns the user attachment
	 * @since 1.3.7
	 **/
	<T> T getAttachment();

	/**
	 * Does this websocket use an encrypted (wss/ssl) or unencrypted (ws) connection
	 * @return true, if the websocket does use wss and therefore has a SSLEngine
	 * @since 1.4.1
	 */
	boolean hasSSLEngine();

	/**
	 * Returns the ssl engine of websocket, if ssl/wss is used for this instance.
	 * @return the ssl engine of this websocket instance
	 * @throws IllegalArgumentException the underlying channel does not use ssl (use hasSSLEngine() to check)
	 * @since 1.4.1
	 */
	SSLEngine getSSLEngine() throws IllegalArgumentException;
}