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docs:3500:0400:0410:0411 [2023/04/05 06:25] – removed - external edit (Unknown date) 127.0.0.1docs:3500:0400:0410:0411 [2025/06/12 02:36] (current) – Rename to AwareIM aware_support3
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 +{{tag>Programmers_Reference Adding_Custom_Channels Source_and_sink Writing_Sink example}}
 +[<10>]
 +==== Writing a Sink ====
 +
 +To write a custom Sink follow the steps below:
 +
 +  - Inherit the Sink from the ''AbstractSimpleSink'' class.
 +  - If necessary override init method to provide the Sink-specific initialization (if there’s any) – this method is called once when the Sink is initialized. The Sink-specific properties would have been entered by the user in the Configuration Tool (see also section 4.3)
 +  - You must override the following method to provide your own handling of messages sent from //**AwareIM**//:<code java>public void processMessage (Message msg) 
 +throws PipelineException;</code> \\ You can translate messages from //**AwareIM**// using the following techniques:
 +      - get the array of DataObject’s from the message:<code java>DataObject [] dobs = msg.peekDataObjects ();</code>
 +      - use MessageInterpreter class to interpret the message (see also 4.1.3):<code java>MessageInterpreter mi = new MessageInterpreter (dobs);
 +INotification notif = mi.getNotification (); /**or**/
 +String serviceName  = mi.getServiceName ();</code>
 +
 +As an example you can see the code snippet below that implements the Sink that sends outgoing e-mails from //**AwareIM**//. Note that this code is for illustration purposes only and certain details such as e-mail construction and sending and error handling are omitted.
 +
 +<code java> public  class EmailSink extends AbstractSimpleSink
 + {
 +    private Stringm_mailHost= null ;
 +    private Sessionm_session= null ;
 +    private Stringm_fromAddress= null ;
 +    /** Initializethesink. Mail host and 'from address' properties are specified in the user interface */
 +    public  void init(Stringname,Propertiesprops,Stringprefix,
 +        Controllercontroller)
 +    throws IbafException
 +    {
 +        try 
 +        {
 +            super .init(name,props,prefix,controller);
 +            m_mailHost=props.getProperty(prefix+"."+"MAIL_HOST");
 +            if (m_mailHost== null )
 +                throw  new IbafException("Mail host property for outgoing e-mails is not specified.");
 +            PropertiessessionProps=System.getProperties();
 +            sessionProps.put("mail.smtp.host",m_mailHost);
 +            m_fromAddress=props.getProperty(prefix+"."+"MAIL_FROM_ADDRESS");
 +            m_session=Session.getDefaultInstance(sessionProps,null);
 +        }
 +        catch (Exceptione)
 +        {
 +            e.printStackTrace();
 +            throw  new IbafException(e.toString());
 +        }
 +    }
 +    /**  Message handling method – must be provided */
 +    public  void processMessage(Message msg)
 +    throws PipelineException
 +    {
 +        Stringsubject= null ,toAddress= null ;
 +        StringsentDateStr= null ;
 +        try 
 +        {
 +            DataObject[]dobs=msg.peekDataObjects();
 +            // get all message parameters from data objects
 +            MessageInterpretermi= new MessageInterpreter(dobs);
 +            // get e-mail address from channel values
 +            DataObjectchvDob=mis.getChannelValues();
 +            if (chvDob== null )
 +            return ; // ignore the message
 +        try 
 +        {
 +            toAddress=(String)chvDob.getAttributeValue(EMAIL_ADDRESS);
 +        }
 +        catch (InvalidParameterExceptionipe)
 +        {
 +
 +        }
 +        if (toAddress== null ) return ;//** ignore the message
 +        INotificationnotif=mis.getNotification();
 +        if (notif== null ) return ; // ignore the message
 +        // we expect notification of a certain structure – it must have "BODY" and SUBJECT attributes defined
 +        Stringbody= null ;
 +        try 
 +        {
 +            body=(String)notif.getAttributeValue (EMAIL_BODY_ATTR);
 +        }
 +        catch (InvalidParameterExceptionipe)
 +        {
 +
 +        }
 +        if (body== null )
 +        return ; // ignore the message// subject is optional
 +        try
 +        {
 +            subject=(String)notif.getAttributeValue (EMAIL_SUBJECT_ATTR);
 +        }
 +        catch (Exceptione)
 +        {
 +        }
 +        if (subject== null ) subject="";
 +        // create MAPI e-mail message
 +        MimeMessageemail=createEmail(body,subject, toAddress);
 +        if (email!= null )
 +        {
 +            // send e-mail using MAPI
 +            sendEmail(email,toAddress,new Date ());
 +        }
 +    }
 +    catch (Exceptione)
 +    {        
 +    }
 +}
 +
 +/**  Send the e-mail using MAPI. A lot of details are omitted  **/
 +private  boolean sendEmail(MimeMessageemail,StringtoAddress, StringsentDate)
 +{
 +    try
 +    {
 +        Transport.send(email);
 +    }
 +    catch (Exceptione)
 +    {
 +    }
 +    return true;
 +}
 +
 +/** Create e-mailmessage using MAPI. Details are omitted */
 +private MimeMessagecreateEmail(Stringbody,Stringsubject,String toAddress,DatesentDate)
 +throws Exception 
 +{
 +    MimeMessagemailMessage= new MimeMessage(m_session);
 +    if (m_fromAddress!= null ) mailMessage.setFrom(InternetAddress.parse mailMessage.setRecipients(javax.mail.Message.RecipientType.TO, InternetAddress.parse(toAddress, false ));
 +        mailMessage.setSubject (subject);
 +        mailMessage.setSentDate(sentDate);
 +        return mailMessage;
 +}</code>