com.uc4.communication

Class WebSocketConnection

java.lang.Object

com.uc4.communication.WebSocketConnection

All Implemented Interfaces:

AEConnection, java.io.Closeable, java.lang.AutoCloseable

@WebSocket
public class WebSocketConnection
extends java.lang.Object
implements AEConnection, java.io.Closeable

This class represents a WebSocketConnection to the UC4 Server. it contains the business logic for exchanging messages with the JCP. This class should not get exposed publicly so that the public WebSocketMethods (onConnect(org.eclipse.jetty.websocket.api.Session), onClose(org.eclipse.jetty.websocket.api.Session, int, java.lang.String), onMessage(String), onMessage(byte[], int, int), onError(java.lang.Throwable), onReceiveFrame(org.eclipse.jetty.websocket.api.Session, org.eclipse.jetty.websocket.api.extensions.Frame)) can only be called internally.

Method Summary

Modifier and Type	Method and Description
void	close() Closes the connection to the UC4 Server.
ConnectionAttributes	getSessionInfo() Returns information about the current UC4 Session.
void	onClose(org.eclipse.jetty.websocket.api.Session session, int statusCode, java.lang.String reason)
void	onConnect(org.eclipse.jetty.websocket.api.Session wsSession) Internal use only
void	onError(java.lang.Throwable cause) Internal use only
void	onMessage(byte[] buf, int offset, int length) Internal use only WebSocket method to receive binary messages
void	onMessage(java.lang.String xml) Internal use only WebSocket method to receive xml messages
void	onReceiveFrame(org.eclipse.jetty.websocket.api.Session session, org.eclipse.jetty.websocket.api.extensions.Frame frame) Internal use only WebSocket method when receiving a Frame - if it is a ping or pong message, a debug message gets written
java.lang.String	sendRequest(XMLRequest sendableMessage, IResponseHandler handler) Sends an message to the UC4 Server.
void	sendRequestAndWait(XMLRequest sendableMessage) Sends a message to the UC4 Server and waits for the response.
java.lang.String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Method Detail

close

public void close()

Closes the connection to the UC4 Server.

Specified by:

close in interface java.io.Closeable

Specified by:

close in interface java.lang.AutoCloseable

sendRequestAndWait

public void sendRequestAndWait(XMLRequest sendableMessage)
                        throws java.io.IOException

Sends a message to the UC4 Server and waits for the response. This method blocks until the response from the UC4 Server is arrived. The API connection is closed if the Thread is interrupted while waiting for a response. Throws TimeoutException if a timeout has been set and the Server did not respond within that time.

When a request is sent with this method, before further processing of the response, the message of the response (see XMLRequest.getMessageBox()) has to be always checked for any error. Only if this is empty the processing of the response can continue.
If an error is present, proper error handling has to be implemented on the calling side.
Processing the unsuccessful response might get undefined results!

Specified by:

sendRequestAndWait in interface AEConnection

Parameters:

sendableMessage - XML request

Throws:

java.io.IOException - If an I/O error occurs

TimeoutException - if a timeout was and a response was not received in the API within the specified time

sendRequest

public java.lang.String sendRequest(XMLRequest sendableMessage,
                                    IResponseHandler handler)
                             throws java.io.IOException

Sends an message to the UC4 Server.

After the request is sent to the UC4 Server the method call returns immediately. When the response to this request arrives the IResponseHandler will be called.

This method does not support creating folders (request CreateObject with type FOLD). Use the method sendRequestAndWait() in order to create a new folder.

Specified by:

sendRequest in interface AEConnection

Parameters:

sendableMessage - Object which implements the XMLRequest Interface

handler - Response Handler

Returns:

Request Number as String.

Throws:

java.io.IOException - If an I/O error occurs

getSessionInfo

public ConnectionAttributes getSessionInfo()

Returns information about the current UC4 Session.

Specified by:

getSessionInfo in interface AEConnection

Returns:

Session information

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

onConnect

@OnWebSocketConnect
public void onConnect(org.eclipse.jetty.websocket.api.Session wsSession)

Internal use only

Parameters:

wsSession - WebSocket session

onClose

@OnWebSocketClose
public void onClose(org.eclipse.jetty.websocket.api.Session session,
                                       int statusCode,
                                       java.lang.String reason)

Parameters:

session - session

statusCode - status code, not used

reason - reason for close, not used

onError

@OnWebSocketError
public void onError(java.lang.Throwable cause)

Internal use only

Parameters:

cause - Error cause

onMessage

@OnWebSocketMessage
public void onMessage(java.lang.String xml)

Internal use only WebSocket method to receive xml messages

Parameters:

xml - Received XML message

onReceiveFrame

@OnWebSocketFrame
public void onReceiveFrame(org.eclipse.jetty.websocket.api.Session session,
                                              org.eclipse.jetty.websocket.api.extensions.Frame frame)

Internal use only WebSocket method when receiving a Frame - if it is a ping or pong message, a debug message gets written

Parameters:

session - session

frame - receivedFrame

onMessage

@OnWebSocketMessage
public void onMessage(byte[] buf,
                                           int offset,
                                           int length)
                                    throws java.io.IOException

Internal use only WebSocket method to receive binary messages

Parameters:

buf - Input message

offset - Offset

length - Length

Throws:

java.io.IOException - In case of IO errors