Simple SMTP send mail application that demonstrates usage of the MailTransport class. More...

Inheritance diagram for SendMailApp:

Collaboration diagram for SendMailApp:

Public Member Functions
	SendMailApp ()
	Creates an instance of the send mail application GUI.
void	clearLog ()
	Clears the log.
void	println (String str)
	Logs message terminated with new line.
void	onSendCompleted (String errorMessage)
	On send completed call-back.
void	actionPerformed (ActionEvent evt)
	Handles events from 'enqueue' and 'send immediately' buttons.
Static Public Member Functions
static void	main (String args[])
	Main entry point.
Private Member Functions
void	enqueueMessage (boolean sendImmediately)
	Enqueues message and optionally flushes the queue.
void	formWindowClosing (WindowEvent evt)
	Closes application gracefully.
Static Private Member Functions
static String	now ()
	Gets current time stamp.
Private Attributes
JButton	buttonEnqueue
	GUI components.
JButton	buttonSend
JLabel	labelServer
JTextField	fieldServer
JLabel	labelFrom
JTextField	fieldFrom
JLabel	labelTo
JTextField	fieldTo
JLabel	labelSubject
JTextField	fieldSubject
JScrollPane	messageScrollPane
JTextArea	messageContents
JTabbedPane	tabbedPane
JScrollPane	logPane
JTextArea	logArea
MailTransport	mailTransport = null
	Instance of the current mail transport channel.
Static Private Attributes
static final long	serialVersionUID = 6679954030573701419L
	Implements java.io.Serializable interface.
static final String	appTitle = "IP1-6.1: SMTP Send Mail"
	Common application title prefix.

Detailed Description

Simple SMTP send mail application that demonstrates usage of the MailTransport class.

It also offers presentation context for instances of MailTransport.

Author:: Mikica B Kocic

Definition at line 32 of file SendMailApp.java.

Constructor & Destructor Documentation

SendMailApp.SendMailApp ( )

Creates an instance of the send mail application GUI.

Definition at line 75 of file SendMailApp.java.

References appTitle, buttonEnqueue, buttonSend, fieldFrom, fieldServer, fieldSubject, fieldTo, formWindowClosing(), labelFrom, labelServer, labelSubject, labelTo, logArea, logPane, messageContents, messageScrollPane, and tabbedPane.

Referenced by main().

    {
        super( appTitle + ", idle" );
            
        setDefaultCloseOperation( WindowConstants.EXIT_ON_CLOSE );
        
        /////////////////////////////////////////////////////// GUI COMPONENTS ///////////
        
        addWindowListener( new java.awt.event.WindowAdapter () {
            public void windowClosing( java.awt.event.WindowEvent evt ) {
                formWindowClosing( evt );
            }
        });

        Font btnFont  = new Font( Font.SANS_SERIF, Font.BOLD,  12 );
        Font textFont = new Font( Font.SANS_SERIF, Font.PLAIN, 15 );
        Font logFont  = new Font( Font.MONOSPACED, Font.PLAIN, 14 );
        
        buttonEnqueue    = new JButton ();
        buttonSend       = new JButton ();
        labelServer      = new JLabel ();
        fieldServer       = new JTextField ();
        labelFrom        = new JLabel ();
        fieldFrom         = new JTextField ();
        labelTo          = new JLabel ();
        fieldTo           = new JTextField ();
        labelSubject     = new JLabel ();
        fieldSubject      = new JTextField ();

        labelServer.setText( "STMP Server:" );
        labelFrom.setText( "From:" );
        labelTo.setText( "To:" );
        labelSubject.setText( "Subject:" );
        
        fieldServer.setColumns( 40 );
        fieldFrom.setColumns( 40 );
        fieldTo.setColumns( 40 );
        fieldSubject.setColumns( 40 );

        buttonEnqueue.setFont( btnFont );
        buttonSend.setFont( btnFont );
        labelServer.setFont( textFont );
        labelFrom.setFont( textFont );
        labelTo.setFont( textFont );
        labelSubject.setFont( textFont );
        fieldServer.setFont( textFont );
        fieldFrom.setFont( textFont );
        fieldTo.setFont( textFont );
        fieldSubject.setFont( textFont );

        messageContents = new JTextArea ();
        messageContents.setLineWrap( true );
        messageContents.setWrapStyleWord( true );
        messageContents.setEditable( true );
        messageContents.setFont( textFont );

        messageScrollPane = new JScrollPane ();
        messageScrollPane.setViewportView( messageContents );
        
        logArea = new JTextArea ();
        logArea.setLineWrap( true );
        logArea.setWrapStyleWord( true );
        logArea.setEditable( false );
        logArea.setFont( logFont );
        logArea.setBackground( new Color( 255, 255, 240 ) );
        logArea.setForeground( Color.BLACK );
        logArea.setWrapStyleWord( true );
        
        logPane = new JScrollPane ();
        logPane.setViewportView( logArea );

        buttonEnqueue.setText( "Enqueue Message" );
        buttonEnqueue.addActionListener( this );

        buttonSend.setText( "Send Immediatelly" );
        buttonSend.addActionListener( this );

        /////////////////////////////////////////////////////// COMPONENTS LAYOUT ////////

        JPanel sendMailPane = new JPanel (); 
        sendMailPane.setBorder( new MetalBorders.Flush3DBorder() );
        
        GroupLayout layout = new GroupLayout( sendMailPane );
        sendMailPane.setLayout( layout );
        layout.setAutoCreateContainerGaps( true );
        layout.setAutoCreateGaps( true );
        
        layout.setHorizontalGroup
        (
            layout
            .createParallelGroup( GroupLayout.Alignment.LEADING )
            .addGroup
            (
                layout
                .createSequentialGroup ()
                .addGroup
                (
                    layout
                    .createParallelGroup( GroupLayout.Alignment.TRAILING )
                    .addComponent( messageScrollPane )
                    .addGroup
                    (
                        GroupLayout.Alignment.LEADING, 
                        layout
                        .createSequentialGroup ()
                        .addContainerGap( 10, 10 )
                        .addGroup
                        (
                            layout
                            .createParallelGroup( GroupLayout.Alignment.LEADING )
                            .addComponent( labelServer )
                            .addComponent( labelFrom )
                            .addComponent( labelTo )
                            .addComponent( labelSubject )
                        )
                        .addGroup
                        (
                            layout
                            .createParallelGroup( GroupLayout.Alignment.LEADING, false )
                            .addComponent( fieldServer )
                            .addComponent( fieldFrom )
                            .addComponent( fieldTo )
                            .addComponent( fieldSubject )
                        )
                    )
                    .addGroup
                    (
                        GroupLayout.Alignment.LEADING,
                        layout
                        .createSequentialGroup ()
                        .addContainerGap( 10, 10 )
                        .addGroup
                        (
                            layout
                            .createParallelGroup( GroupLayout.Alignment.LEADING, false )
                            .addComponent( buttonEnqueue )
                        )
                        .addGroup
                        (
                            layout
                            .createParallelGroup( GroupLayout.Alignment.LEADING, false )
                            .addComponent( buttonSend )
                        )
                    )
                )
            )
        );
        
        layout.setVerticalGroup
        (
            layout
            .createParallelGroup( GroupLayout.Alignment.LEADING )
            .addGroup
            (
                layout
                .createSequentialGroup ()
                .addGroup
                (
                    layout
                    .createParallelGroup( GroupLayout.Alignment.BASELINE )
                    .addComponent( labelServer )
                    .addComponent( fieldServer )
                )
                .addGroup
                (
                    layout
                    .createParallelGroup( GroupLayout.Alignment.BASELINE )
                    .addComponent( labelFrom )
                    .addComponent( fieldFrom )
                )
                .addGroup
                (
                    layout
                    .createParallelGroup( GroupLayout.Alignment.BASELINE )
                    .addComponent( labelTo )
                    .addComponent( fieldTo )
                )
                .addGroup
                (
                    layout.createParallelGroup( GroupLayout.Alignment.BASELINE )
                    .addComponent( labelSubject )
                    .addComponent( fieldSubject )
                )
                .addGroup
                (
                    layout.createParallelGroup( GroupLayout.Alignment.BASELINE )
                    .addComponent( buttonEnqueue )
                    .addComponent( buttonSend )
                )
                .addComponent( messageScrollPane )
            )
        );

        pack ();

        /////////////////////////////////////////////////////// TABBED PANES /////////////
        
        tabbedPane = new JTabbedPane ();
        getContentPane().add( tabbedPane );
        tabbedPane.addTab( "Compose Message", sendMailPane );
        tabbedPane.addTab( "MTA: Idle", logPane );

        /////////////////////////////////////////////////////// WINDOW PLACEMENT /////////
        
        /* Adjust window dimensions not to exceed screen dimensions ...
         */
        Dimension win = new Dimension( 695, 590 );
        Dimension scsz = Toolkit.getDefaultToolkit().getScreenSize();
        win.width  = Math.min( win.width, scsz.width );
        win.height = Math.min( win.height, scsz.height - 40 );
        setMinimumSize( win );
        setSize( win );
        
        /* ... then center window on the screen.
         */
        setLocation( ( scsz.width - win.width )/2, ( scsz.height - 40 - win.height )/2 );
        
        /* Ready for user to type in...
         */
        fieldServer.requestFocus ();
    }

Member Function Documentation

void SendMailApp.actionPerformed ( ActionEvent evt )

Handles events from 'enqueue' and 'send immediately' buttons.

Definition at line 500 of file SendMailApp.java.

References buttonSend, and enqueueMessage().

    {
        boolean sendImmediately = ( evt.getSource () == buttonSend );
        
        enqueueMessage( sendImmediately );
    }

void SendMailApp.clearLog ( )

Clears the log.

Definition at line 399 of file SendMailApp.java.

References logArea.

    {
        synchronized( logArea )
        {
            logArea.setText( "" );
            logArea.setRows( 0 );
            logArea.setCaretPosition( logArea.getText().length () );
        }
    }

void SendMailApp.enqueueMessage ( boolean sendImmediately ) [private]

Enqueues message and optionally flushes the queue.

It creates new instance of the mail transport channel (if there is no any and also keeps GUI elements synchronized with the current state of the mail transport instance.

Definition at line 302 of file SendMailApp.java.

References appTitle, MailTransport.enqueueMessage(), fieldFrom, fieldServer, fieldSubject, fieldTo, MailTransport.getQueueSize(), mailTransport, messageContents, MailTransport.noMoreMessages(), println(), MailTransport.startSending(), and tabbedPane.

Referenced by actionPerformed().

    {
        try 
        {
            /* Create new instance of mail transport (if there is no any) and lock the 
             * server input field so the user cannot change server name 
             * until the queue is flushed (because all subsequent messages
             * will be enqueued in the queue of the currently created MailTransport
             * instance). 
             */
            synchronized( this ) 
            {
                if ( mailTransport == null ) {
                    mailTransport = new MailTransport( this, fieldServer.getText(), 25 );
                    fieldServer.setEnabled( false );
                }
            }

            /* Now, create and put the message into sending queue of the mail transport...
             */
            String   from       = fieldFrom.getText().trim(); 
            String[] recipients = fieldTo.getText().trim().split(",");
            String   subject    = fieldSubject.getText().trim();
            String   contents   = messageContents.getText().trim();
           
            /* Enqueue message only if there is recipient specified
             */
            if ( recipients.length > 0 && ! recipients[0].isEmpty () )
            {
                mailTransport.enqueueMessage( from, recipients, subject, contents );

                int msgCount = mailTransport.getQueueSize ();
                assert msgCount > 0 
                    : "Ouch!. We have enqueued message, but the queue is still empty?";
                if ( msgCount == 1 ) {
                    setTitle( appTitle + ", 1 message waiting to be sent..." );
                } else {
                    setTitle( appTitle + ", " + msgCount 
                            + " messages waiting to be sent..." );
                }
                
                /* Keep "From:" field and clear other variable fields
                 */
                fieldTo.setText( "" );
                fieldSubject.setText( "" );
                messageContents.setText( "" );
            }
            
            /* If user wants to flush the queue, then start the worker thread
             * and indicate that we have no more messages to send, then release
             * mailTransport agent.
             */
            if ( sendImmediately && mailTransport.getQueueSize () > 0 )
            {
                println( "------------------------------------------------------------" );

                tabbedPane.setForegroundAt( 1, Color.BLUE );
                tabbedPane.setTitleAt( 1, "MTA: Sending..." );
                tabbedPane.setSelectedIndex( 1 );
                setTitle( appTitle + ", Sending messages..." );
                
                mailTransport.noMoreMessages ();
                mailTransport.startSending ();
                
                /* Release mailTransport agent and unlock the server field
                 */
                mailTransport = null;
                fieldServer.setEnabled( true );
            }
            else if ( mailTransport.getQueueSize () == 0 )
            {
                tabbedPane.setForegroundAt( 1, Color.BLACK );
                tabbedPane.setTitleAt( 1, "MTA: Idle" );
                setTitle( appTitle + ", idle" );
                
                /* Release mailTransport agent and unlock the server field
                 */
                mailTransport = null;
                fieldServer.setEnabled( true );
            }
            else
            {
                tabbedPane.setForegroundAt( 1, Color.BLACK );
                tabbedPane.setTitleAt( 1, "MTA: Idle" );
            }
        }
        catch( MessagingException e )
        {
            JOptionPane.showMessageDialog( this, 
                    "Failed to put e-mail message into the queue\n" + e.toString (), 
                    "Error while enqueing the message...", JOptionPane.ERROR_MESSAGE );
        }
    }

void SendMailApp.formWindowClosing ( WindowEvent evt ) [private]

Closes application gracefully.

Parameters:

evt

Definition at line 482 of file SendMailApp.java.

References mailTransport, and MailTransport.noMoreMessages().

Referenced by SendMailApp().

    {
        /* Signal to mail transport's worker thread to flush the queue before exit
         */
        synchronized( this ) 
        {
            if ( mailTransport != null ) {
                mailTransport.noMoreMessages ();
                mailTransport = null;
            }
        }

        System.exit( 0 );
    }

static void SendMailApp.main ( String args[] ) [static]

Main entry point.

Creates instance of SendMailApp application.

Parameters:

args	the command line arguments

Definition at line 512 of file SendMailApp.java.

References SendMailApp().

    {
        java.awt.EventQueue.invokeLater( 
                new Runnable() {
                    public void run() {
                        new SendMailApp ().setVisible( true );
                    }
                }
            );
    }

static String SendMailApp.now ( ) [static, private]

Gets current time stamp.

Returns:: time in ISO format

Definition at line 414 of file SendMailApp.java.

Referenced by println().

    {
        Calendar cal = Calendar.getInstance ();
        SimpleDateFormat sdf = new SimpleDateFormat( "yyyy-MM-dd HH:mm:ss" );
        return sdf.format( cal.getTime() );
    }

void SendMailApp.onSendCompleted ( String errorMessage ) [virtual]

On send completed call-back.

Parameters:

errorMessage contains an error message if not null, otherwise success

Implements MailTransport.Context.

Definition at line 442 of file SendMailApp.java.

References appTitle, MailTransport.getQueueSize(), mailTransport, and tabbedPane.

    {
        synchronized ( this )
        {
            int msgCount = mailTransport == null ? 0 : mailTransport.getQueueSize ();
            if ( msgCount == 0 ) {
                setTitle( appTitle + ", idle" );
            } else if ( msgCount == 1 ) {
                setTitle( appTitle + ", 1 message waiting to be sent..." );
            } else {
                setTitle( appTitle + ", " + msgCount 
                        + " messages waiting to be sent..." );
            }
        }

        if ( errorMessage != null ) {
            // tabbedPane.setSelectedIndex( 1 );
            tabbedPane.setForegroundAt( 1, Color.RED );
            tabbedPane.setTitleAt( 1, "MTA: Error!" );

            /* Commented because we don't want to disturb user...
             * 
            JOptionPane.showMessageDialog( this, 
                    "Failed to send e-mail messages from queue!\n"
                    + "Please, check the log for more details...\n"
                    + errorMessage,
                    "Error while flushing the queue...", 
                    JOptionPane.ERROR_MESSAGE );
            */
        } else {
            tabbedPane.setForegroundAt( 1, new Color( 0, 128, 0 ) ); // dark green
            tabbedPane.setTitleAt( 1, "MTA: OK" );
        }
    }

void SendMailApp.println ( String str ) [virtual]

Logs message terminated with new line.

Parameters:

str	message that will be logged

Implements MailTransport.Context.

Definition at line 427 of file SendMailApp.java.

References logArea, and now().

Referenced by enqueueMessage().

    {
        synchronized( logArea )
        {
            logArea.append( now () + "  " + str + "\n" );
            logArea.setRows( logArea.getRows () + 1 );
            logArea.setCaretPosition( logArea.getText().length () );
        }
    }