General Event Handling (Outside AWT)

Hi all, I am looking for info on allowing my classes to send and recieve events between classes (the set of events is to be defined by me). What is Java's event handling approach? Is there something outside the AWT?
I realise there may be design patterns for this scenario but though there may be some Java specific way as well (like in the AWT).
Thanks,
David

listeners.
like this...
FooEvent <- your event class
FooEventListener <- listener interface
FooMaker <- class that generates foo events
An interface for the listener.
public interface FooEventListener{
  public void processEvent(FooEvent evt);
}the class making the events
public FooMaker{
  // among other things might have methods like...
  public void addFooEventListener(FooEventListener fel){
    // add the listener to some collection
  // called when events happen
  private void notifyListeners(){
     // notify each listener
}and your listeners will implement the interface.
does that help?

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         int status_a;
         int status_b;
         int status_c;
    /* deletion of code segment a
              span = 0;
              chord = 0;
              thickness = 0;
              mass = 0;
              altitude = 0;
              velocity = 0;
              trajectory_angle = 0;
              time_increment = 0;
              rotation_factor = 0;
              distance = 0;
              velocity_fps = 0;
              elapsed_time = 0;
              velocity_fps = 0;
              elapsed_time = 0;
         // create objects
         public void init()
              status_a = 0;
              status_b = 0;
              status_c = 0;
              // create container & panel
              Container container = getContentPane();     
              Panel panel = new Panel( new FlowLayout( FlowLayout.LEFT));
              container.add( panel );
              // set up vertical boxlayout
              Box box = Box.createVerticalBox();
              Box inputbox1 = Box.createHorizontalBox();
              Box inputbox2 = Box.createHorizontalBox();
              Box inputbox3 = Box.createHorizontalBox();
              Box buttonbox = Box.createHorizontalBox();
              introduction_string = "This is the introduction";
              // set up introduction
              introductionArea = new JTextArea( introduction_string, 10, 50 );
              introductionArea.setEditable( false );
              box.add( new JScrollPane( introductionArea ) );
              box.add( Box.createVerticalStrut (10) );
              box.add( inputbox1);
              // set up span
              spanLabel = new JLabel( "span (feet)" );
              spanField = new JTextField(5 );
              inputbox1.add( spanLabel );
              inputbox1.add( spanField );
              Dimension minSize = new Dimension(5, 15);
              Dimension prefSize = new Dimension(5, 15);
              Dimension maxSize = new Dimension(Short.MAX_VALUE, 15);
              inputbox1.add(new Box.Filler(minSize, prefSize, maxSize));
              // set up chord
              chordLabel = new JLabel( "chord (feet)" );
              chordField = new JTextField(5 );
              inputbox1.add( chordLabel );
              inputbox1.add( chordField );
              inputbox1.add(new Box.Filler(minSize, prefSize, maxSize));
              // set up thickness
              thicknessLabel = new JLabel( "thickness (feet)" );
              thicknessField = new JTextField(5 );
              inputbox1.add( thicknessLabel );
              inputbox1.add( thicknessField );
              inputbox1.add(new Box.Filler(minSize, prefSize, maxSize));
              // set up mass
              massLabel = new JLabel( "mass (slugs)" );
              massField = new JTextField(5);
              inputbox1.add( massLabel );
              inputbox1.add( massField );
              box.add( Box.createVerticalStrut (10) );
              box.add( inputbox2);
              // set up altitude
              altitudeLabel = new JLabel( "altitude (feet)");
              altitudeField = new JTextField(5 );
              inputbox2.add( altitudeLabel );
              inputbox2.add( altitudeField );
              inputbox2.add(new Box.Filler(minSize, prefSize, maxSize));
              // set up velocity
              velocityLabel = new JLabel( "velocity (Mach Number)");
              velocityField = new JTextField(5);
              inputbox2.add( velocityLabel );
              inputbox2.add( velocityField );
              inputbox2.add(new Box.Filler(minSize, prefSize, maxSize));
              // set up trajectory_angle
              trajectory_angleLabel = new JLabel( "trajectory angle ( -90 degrees <= trajectory angle <= 90 degrees )");
              trajectory_angleField = new JTextField(5);
              inputbox2.add( trajectory_angleLabel );
              inputbox2.add( trajectory_angleField );
              box.add( Box.createVerticalStrut (10) );
              box.add( inputbox3);
              Dimension minSizeF = new Dimension(70, 15);
              Dimension prefSizeF = new Dimension(70, 15);
              Dimension maxSizeF = new Dimension(Short.MAX_VALUE, 15);
              inputbox3.add(new Box.Filler(minSizeF, prefSizeF, maxSizeF));
              // set up time_increment
              time_incrementLabel = new JLabel( "time increment (seconds)" );
              time_incrementField = new JTextField(5);
              inputbox3.add( time_incrementLabel );
              inputbox3.add( time_incrementField );
              inputbox3.add(new Box.Filler(minSizeF, prefSizeF, maxSizeF));
              // set up rotation_factor
              rotation_factorLabel = new JLabel( "rotation factor ( non-negative number)" );
              rotation_factorField = new JTextField(5);
              inputbox3.add( rotation_factorLabel );
              inputbox3.add( rotation_factorField );
              inputbox3.add(new Box.Filler(minSizeF, prefSizeF, maxSizeF));
              box.add( Box.createVerticalStrut (10) );
              box.add( buttonbox);
              // set up start
              startButton = new JButton( "START" );
              buttonbox.add( startButton );
              Dimension minSizeB = new Dimension(10, 30);
              Dimension prefSizeB = new Dimension(10, 30);
              Dimension maxSizeB = new Dimension(Short.MAX_VALUE, 30);
              buttonbox.add(new Box.Filler(minSizeB, prefSizeB, maxSizeB));
              // set up reset
              resetButton = new JButton( "RESET" );
              buttonbox.add( resetButton );
              buttonbox.add(new Box.Filler(minSizeB, prefSizeB, maxSizeB));
              // set up cont
              contButton = new JButton( "CONTINUE" );
              buttonbox.add( contButton );
              buttonbox.add(new Box.Filler(minSizeB, prefSizeB, maxSizeB));
              // set up term
              termButton = new JButton( "END" );
              buttonbox.add( termButton );
              box.add( Box.createVerticalStrut (10) );          
              // set up results
              resultsArea = new JTextArea( results_string, 10, 50 );
              resultsArea.setEditable( false );
              box.add( new JScrollPane( resultsArea ) );
              // add box to panel
              panel.add( box );
              // register event handlers
              Handler handler = new Handler();
              spanField.addActionListener( handler );
              chordField.addActionListener( handler );          
              thicknessField.addActionListener( handler );
              massField.addActionListener( handler );
              altitudeField.addActionListener( handler );
              velocityField.addActionListener( handler );          
              trajectory_angleField.addActionListener( handler );
              time_incrementField.addActionListener( handler );
              rotation_factorField.addActionListener( handler );
              startButton.addActionListener( handler );
              resetButton.addActionListener( handler );
              contButton.addActionListener( handler );
              termButton.addActionListener( handler );
    // private inner class for event handling
    private class Handler implements ActionListener {
         // process handler events
         public void actionPerformed( ActionEvent event )
              // process resetButton event
              if ( event.getSource() == resetButton )
                   reset();
              // process contButton event
              if ( event.getSource() == contButton )
                   cont();
              // process endButton event
              if ( event.getSource() == termButton )
              // process span event
              if( event.getSource() == spanField ) {
                   span = Double.parseDouble( event.getActionCommand() );
                   spanField.setText( span_string );
                   status_b++;
              // process chord event
              if( event.getSource() == spanField ) {
                   span = Double.parseDouble( event.getActionCommand() );
                   spanField.setText( chord_string );
                   status_b++;     
              // process thickness event
              if( event.getSource() == thicknessField ) {
                   thickness = Double.parseDouble( event.getActionCommand() );
                   spanField.setText( thickness_string );     
                   status_b++;
              // process mass event
              if( event.getSource() == massField ) {
                   mass = Double.parseDouble( event.getActionCommand() );
                   spanField.setText( mass_string );
                   status_b++;     
              // process altitude event
              if( event.getSource() == altitudeField ) {
                   altitude = Double.parseDouble( event.getActionCommand() );
                   spanField.setText( altitude_string );     
                   status_b++;
              // process velocity event
              if( event.getSource() == velocityField ) {
                   velocity = Double.parseDouble( event.getActionCommand() );
                   spanField.setText( velocity_string );
                   status_b++;
              // process trajectory_angle event
              if( event.getSource() == trajectory_angleField ) {
                   trajectory_angle = Double.parseDouble( event.getActionCommand() );
                   spanField.setText( trajectory_angle_string );
                   status_b++;
              // process time_increment event
              if( event.getSource() == time_incrementField ) {
                   time_increment = Double.parseDouble( event.getActionCommand() );
                   spanField.setText( time_increment_string );
                   status_b++;
              // process rotation_factor event
              if( event.getSource() == rotation_factorField ) {
                   rotation_factor = Double.parseDouble( event.getActionCommand() );
                   spanField.setText( rotation_factor_string );
                   status_b++;
              // process startButton event
              if ( event.getSource() == startButton && status_b == 9 ) {
                   status_c = 1;
         } // end method event handler
    } // end Handler class
         } // end method init
         public void strtb()
    /* deletion of code segment 1
              startButton.addActionListener(
                   new ActionListener() {  // anonymous inner class
                        // set text in resultsArea
                        public void actionPerformed( ActionEvent event )
                        if( status_c == 1 ){
                        calculate();
                        results();
                        resultsArea.setText( results() );
    /* deletion of code segment 2                    
                        }// end method actionPerformed1
                   } // end anonymous inner class1
              ); // end call to addActionlistener1
         } // end method strtb
         public void reset()
    /* deletion of code segment 3
              resetButton.addActionListener(
                   new ActionListener() {  // anonymous inner class
                        // set text in resultsArea
                        public void actionPerformed( ActionEvent event )
                        span_string = "";
                        chord_string = "";
                        thickness_string = "";
                        mass_string = "";
                        altitude_string = "";
                        velocity_string = "";
                        trajectory_angle_string = "";
                        time_increment_string = "";
                        rotation_factor_string = "";
                        results_string = "";
                        spanField.setText( span_string );
                        chordField.setText( chord_string );
                        thicknessField.setText( thickness_string );
                        massField.setText( mass_string );
                        altitudeField.setText( altitude_string );
                        velocityField.setText( velocity_string );
                        trajectory_angleField.setText( trajectory_angle_string );
                        time_incrementField.setText( time_increment_string );
                        rotation_factorField.setText( rotation_factor_string );
    resultsArea.setEditable( true );
                        resultsArea.setText( results_string );
    resultsArea.setEditable( false );
                        span = 0;
                        chord = 0;
                        thickness = 0;
                        mass = 0;
                        altitude = 0;
                        velocity = 0;
                        trajectory_angle = 0;
                        time_increment = 0;
                        rotation_factor = 0;
                        distance = 0;
                        velocity_fps = 0;
                        elapsed_time = 0;
    /* deletion of code segment 4               
                        } // end method actionPerformed2
                   } // end anonymous inner class2
              ); // end call to addActionlistener2
         } // end method reset
         public void cont()
         //later
         public void calculate()
         distance = 1;
         altitude = 2;
         trajectory_angle = 3;
         velocity_fps = 4;
         elapsed_time = 5;
         public String results()
         results_string =
         "Distance =\t\t" + distance + " miles\n"
         + "Altitude =\t\t" + altitude + " feet\n"
         + "Trajectory Angle =\t" + trajectory_angle + " degrees\n"
         + "Velocity =\t\t" + velocity_fps + " feet per second\n"
         + "Elapsed Time =\t\t" + elapsed_time + " seconds\n"
         + "\nstatus_a = " + status_a + "\nstatus_b = "
         + status_b + "\nstatus_c = " + status_c;
         return results_string;
    public void start()
    if(status_a == 0 )
    strtb();
    if (status_b == 0)
    reset();
    }// end method start
    } //end class trajectory_a

    The following are copies of html and java source code files for a prior runnable version ( trajectory_b ) of this program which can enlighten some functionality intended by the program.
    (trajectory_b.html):
    <html>
    <appletcode = "trajectory_b.class" width = "800" height = "600">
    </applet>
    </html>
    (trajectory_b.java):
    // trajectory Analysis Program: trajectory_b.java
    import java.awt.*;
    import java.awt.event.*;
    import javax.swing.*;
    public class trajectory_b extends JApplet implements ActionListener {
         private JTextArea introductionArea, resultsArea;
         private JLabel spanLabel, chordLabel,
              thicknessLabel, massLabel, altitudeLabel, velocityLabel,
              trajectory_angleLabel, time_incrementLabel, rotation_factorLabel,
              calculationLabel, resultsLabel;
         private JTextField spanField, chordField, thicknessField,
              massField, altitudeField, velocityField, trajectory_angleField,
              time_incrementField, rotation_factorField;
         private JButton startButton, resetButton, contButton, termButton;
         String introduction_string, span_string, chord_string, thickness_string, mass_string,
              altitude_string, velocity_string, trajectory_angle_string,
              time_increment_string, rotation_factor_string, results_string;
         double span, chord, thickness, mass, altitude, velocity, trajectory_angle, time_increment,
              rotation_factor, distance, velocity_fps, elapsed_time;
         int status_a;
         int status_b;
         int status_c;
    /* deletion of code segment a
              span = 0;
              chord = 0;
              thickness = 0;
              mass = 0;
              altitude = 0;
              velocity = 0;
              trajectory_angle = 0;
              time_increment = 0;
              rotation_factor = 0;
              distance = 0;
              velocity_fps = 0;
              elapsed_time = 0;
              velocity_fps = 0;
              elapsed_time = 0;
         // create objects
         public void init()
              status_a = 0;
              status_b = 0;
              status_c = 0;
              // create container & panel
              Container container = getContentPane();     
              Panel panel = new Panel( new FlowLayout( FlowLayout.LEFT));
              container.add( panel );
              // set up vertical boxlayout
              Box box = Box.createVerticalBox();
              Box inputbox1 = Box.createHorizontalBox();
              Box inputbox2 = Box.createHorizontalBox();
              Box inputbox3 = Box.createHorizontalBox();
              Box buttonbox = Box.createHorizontalBox();
              introduction_string = "This is the introduction";
              // set up introduction
              introductionArea = new JTextArea( introduction_string, 10, 50 );
              introductionArea.setEditable( false );
              box.add( new JScrollPane( introductionArea ) );
              box.add( Box.createVerticalStrut (10) );
              box.add( inputbox1);
              // set up span
              spanLabel = new JLabel( "span (feet)" );
              spanField = new JTextField(5 );
              inputbox1.add( spanLabel );
              inputbox1.add( spanField );
              Dimension minSize = new Dimension(5, 15);
              Dimension prefSize = new Dimension(5, 15);
              Dimension maxSize = new Dimension(Short.MAX_VALUE, 15);
              inputbox1.add(new Box.Filler(minSize, prefSize, maxSize));
              // set up chord
              chordLabel = new JLabel( "chord (feet)" );
              chordField = new JTextField(5 );
              inputbox1.add( chordLabel );
              inputbox1.add( chordField );
              inputbox1.add(new Box.Filler(minSize, prefSize, maxSize));
              // set up thickness
              thicknessLabel = new JLabel( "thickness (feet)" );
              thicknessField = new JTextField(5 );
              inputbox1.add( thicknessLabel );
              inputbox1.add( thicknessField );
              inputbox1.add(new Box.Filler(minSize, prefSize, maxSize));
              // set up mass
              massLabel = new JLabel( "mass (slugs)" );
              massField = new JTextField(5);
              inputbox1.add( massLabel );
              inputbox1.add( massField );
              box.add( Box.createVerticalStrut (10) );
              box.add( inputbox2);
              // set up altitude
              altitudeLabel = new JLabel( "altitude (feet)");
              altitudeField = new JTextField(5 );
              inputbox2.add( altitudeLabel );
              inputbox2.add( altitudeField );
              inputbox2.add(new Box.Filler(minSize, prefSize, maxSize));
              // set up velocity
              velocityLabel = new JLabel( "velocity (Mach Number)");
              velocityField = new JTextField(5);
              inputbox2.add( velocityLabel );
              inputbox2.add( velocityField );
              inputbox2.add(new Box.Filler(minSize, prefSize, maxSize));
              // set up trajectory_angle
              trajectory_angleLabel = new JLabel( "trajectory angle ( -90 degrees <= trajectory angle <= 90 degrees )");
              trajectory_angleField = new JTextField(5);
              inputbox2.add( trajectory_angleLabel );
              inputbox2.add( trajectory_angleField );
              box.add( Box.createVerticalStrut (10) );
              box.add( inputbox3);
              Dimension minSizeF = new Dimension(70, 15);
              Dimension prefSizeF = new Dimension(70, 15);
              Dimension maxSizeF = new Dimension(Short.MAX_VALUE, 15);
              inputbox3.add(new Box.Filler(minSizeF, prefSizeF, maxSizeF));
              // set up time_increment
              time_incrementLabel = new JLabel( "time increment (seconds)" );
              time_incrementField = new JTextField(5);
              inputbox3.add( time_incrementLabel );
              inputbox3.add( time_incrementField );
              inputbox3.add(new Box.Filler(minSizeF, prefSizeF, maxSizeF));
              // set up rotation_factor
              rotation_factorLabel = new JLabel( "rotation factor ( non-negative number)" );
              rotation_factorField = new JTextField(5);
              inputbox3.add( rotation_factorLabel );
              inputbox3.add( rotation_factorField );
              inputbox3.add(new Box.Filler(minSizeF, prefSizeF, maxSizeF));
              box.add( Box.createVerticalStrut (10) );
              box.add( buttonbox);
              // set up start
              startButton = new JButton( "START" );
              buttonbox.add( startButton );
              Dimension minSizeB = new Dimension(10, 30);
              Dimension prefSizeB = new Dimension(10, 30);
              Dimension maxSizeB = new Dimension(Short.MAX_VALUE, 30);
              buttonbox.add(new Box.Filler(minSizeB, prefSizeB, maxSizeB));
              // set up reset
              resetButton = new JButton( "RESET" );
              buttonbox.add( resetButton );
              buttonbox.add(new Box.Filler(minSizeB, prefSizeB, maxSizeB));
              // set up cont
              contButton = new JButton( "CONTINUE" );
              buttonbox.add( contButton );
              buttonbox.add(new Box.Filler(minSizeB, prefSizeB, maxSizeB));
              // set up term
              termButton = new JButton( "END" );
              buttonbox.add( termButton );
              box.add( Box.createVerticalStrut (10) );          
              // set up results
              resultsArea = new JTextArea( results_string, 10, 50 );
              resultsArea.setEditable( false );
              box.add( new JScrollPane( resultsArea ) );
              // add box to panel
              panel.add( box );
              // register event handlers
              Handler handler = new Handler();
              spanField.addActionListener( handler );
              chordField.addActionListener( handler );          
              thicknessField.addActionListener( handler );
              massField.addActionListener( handler );
              altitudeField.addActionListener( handler );
              velocityField.addActionListener( handler );          
              trajectory_angleField.addActionListener( handler );
              time_incrementField.addActionListener( handler );
              rotation_factorField.addActionListener( handler );
              startButton.addActionListener( handler );
              resetButton.addActionListener( handler );
              contButton.addActionListener( handler );
              termButton.addActionListener( handler );
    } // end method init
         // process handler events
         public void actionPerformed( ActionEvent event )
              // process resetButton event
              if ( event.getSource() == resetButton )
                   reset();
              // process contButton event
              if ( event.getSource() == contButton )
                   cont();
              // process endButton event
              if ( event.getSource() == termButton )
              // process span event
              if( event.getSource() == spanField ) {
                   span = Double.parseDouble( event.getActionCommand() );
                   spanField.setText( span_string );
                   status_b++;
              // process chord event
              if( event.getSource() == spanField ) {
                   span = Double.parseDouble( event.getActionCommand() );
                   spanField.setText( chord_string );
                   status_b++;     
              // process thickness event
              if( event.getSource() == thicknessField ) {
                   thickness = Double.parseDouble( event.getActionCommand() );
                   spanField.setText( thickness_string );     
                   status_b++;
              // process mass event
              if( event.getSource() == massField ) {
                   mass = Double.parseDouble( event.getActionCommand() );
                   spanField.setText( mass_string );
                   status_b++;     
              // process altitude event
              if( event.getSource() == altitudeField ) {
                   altitude = Double.parseDouble( event.getActionCommand() );
                   spanField.setText( altitude_string );     
                   status_b++;
              // process velocity event
              if( event.getSource() == velocityField ) {
                   velocity = Double.parseDouble( event.getActionCommand() );
                   spanField.setText( velocity_string );
                   status_b++;
              // process trajectory_angle event
              if( event.getSource() == trajectory_angleField ) {
                   trajectory_angle = Double.parseDouble( event.getActionCommand() );
                   spanField.setText( trajectory_angle_string );
                   status_b++;
              // process time_increment event
              if( event.getSource() == time_incrementField ) {
                   time_increment = Double.parseDouble( event.getActionCommand() );
                   spanField.setText( time_increment_string );
                   status_b++;
              // process rotation_factor event
              if( event.getSource() == rotation_factorField ) {
                   rotation_factor = Double.parseDouble( event.getActionCommand() );
                   spanField.setText( rotation_factor_string );
                   status_b++;
              // process startButton event
              if ( event.getSource() == startButton && status_b == 9 ) {
                   strtb();
         } // end method event handler
         public void strtb()
              startButton.addActionListener(
                   new ActionListener() {  // anonymous inner class
                        // set text in resultsArea
                        public void actionPerformed( ActionEvent event )
                        calculate();
                        results();
                        resultsArea.setText( results() );
                        }// end method actionPerformed1
                   } // end anonymous inner class1
              ); // end call to addActionlistener1
         } // end method strtb
         public void reset()
              resetButton.addActionListener(
                   new ActionListener() {  // anonymous inner class
                        // set text in resultsArea
                        public void actionPerformed( ActionEvent event )
                        span_string = "";
                        chord_string = "";
                        thickness_string = "";
                        mass_string = "";
                        altitude_string = "";
                        velocity_string = "";
                        trajectory_angle_string = "";
                        time_increment_string = "";
                        rotation_factor_string = "";
                        results_string = "";
                        spanField.setText( span_string );
                        chordField.setText( chord_string );
                        thicknessField.setText( thickness_string );
                        massField.setText( mass_string );
                        altitudeField.setText( altitude_string );
                        velocityField.setText( velocity_string );
                        trajectory_angleField.setText( trajectory_angle_string );
                        time_incrementField.setText( time_increment_string );
                        rotation_factorField.setText( rotation_factor_string );
    resultsArea.setEditable( true );
                        resultsArea.setText( results_string );
    resultsArea.setEditable( false );
                        span = 0;
                        chord = 0;
                        thickness = 0;
                        mass = 0;
                        altitude = 0;
                        velocity = 0;
                        trajectory_angle = 0;
                        time_increment = 0;
                        rotation_factor = 0;
                        distance = 0;
                        velocity_fps = 0;
                        elapsed_time = 0;
                        } // end method actionPerformed2
                   } // end anonymous inner class2
              ); // end call to addActionlistener2
         } // end method reset
         public void cont()
         //later
         public void calculate()
         distance = 1;
         altitude = 2;
         trajectory_angle = 3;
         velocity_fps = 4;
         elapsed_time = 5;
         public String results()
         results_string =
         "Distance =\t\t" + distance + " miles\n"
         + "Altitude =\t\t" + altitude + " feet\n"
         + "Trajectory Angle =\t" + trajectory_angle + " degrees\n"
         + "Velocity =\t\t" + velocity_fps + " feet per second\n"
         + "Elapsed Time =\t\t" + elapsed_time + " seconds\n"
         + "\nstatus_a = " + status_a + "\nstatus_b = "
         + status_b + "\nstatus_c = " + status_c;
         return results_string;
    public void start()
    if(status_a == 0 )
    strtb();
    if (status_b == 0)
    reset();
    }// end method start
    } //end class trajectory_b

  • Event Handling in Fullscreen Exclusive Mode???????

    WIndows XP SP2
    ATI 8500 All-In-Wonder
    JDK 1.6
    800x600 32dpi 200 refresh
    1-6 buffer strategy.
    the graphic rendering thread DOESN'T sleep.
    Here's my problem. I have a bad trade off. In fullscreen exclusive mode my animation runs <30 fps and jerks when rendering. i.e. stop and go movement (not flickering/jittering just hesitant motion) when the animation is running. I solved this problem by raising the thread priority of the rendering (7-8). . . this resulted in latency/no activity for my input events both key and mouse. For instance closing the program alt-f4 will arbitrarily fail or be successful when the thread priority is raised above 6.
    How does one accomplish a >30 fps and Instant event handling simultaneously in Fullscreen Exclusive Mode?
    Is there a way to raise thread priority for event handling?
    Ultimately I want to be able to perform my animations and handle key and mouse input events without having a visible 'hiccups' on the screen.
    Much Appreciated!

    If I remember correctly the processor is a 1.4(or)6ghz AMD Duron
    Total = 1048048kb
    Available = 106084kb
    Sys Cache = 211788kb
    PF Usage = 1.01 GB
    I solved some of the problem after posting this thread. . . .
    I inserted a thread.sleep(1) and my alt-f4 operation worked unhindered with the elevated thread priority.
    I haven't tested it with mouse event or any other key event but at the moment it looks I may have solved the problem.
    If so, my next question will be is there a way to reduce the amount of cpu power needed to run the program.
    I'm afraid that the other classes that I'm adding will actually become even more process consuming than the actually rendering thread.
    public class RenderScreen extends Thread
      // Screen Rendering status code
      protected final static int RUNNING = 0,
                                 PAUSED = -1;
      // frames per second and process time counters
      protected long now = 0, fps = 0, fpsCount = 0, cycTime = 0;
      // thread status
      protected int status = 0;
      protected Screen screen;
      public void setStatus(int i){ status = i; };
      public void setTarget(Screen screen){ this.screen=screen; };
      public void run()
        setName("Screen Render");
        screen.createBufferStrategy(1);
        screen.strategy = screen.getBufferStrategy();
        for(;;)
          if(status == RUNNING)
            now = System.currentTimeMillis();
            while(System.currentTimeMillis() <= now+1000)
              // call system processes
              // fps increment / repaint interface
              fpsCount++;
              screen.renderView();
              try { Thread.sleep(1);}catch(InterruptedException ie){ ie.printStackTrace(); }
            fps = fpsCount;
            cycTime = System.currentTimeMillis() - (now + 1000);
            fpsCount=0;
      public RenderScreen(){};
      public RenderScreen(Screen screen){ this.screen=screen; };
    import java.awt.*;
    import java.awt.event.*;
    import java.awt.image.*;
    import javax.swing.*;
    public class Screen extends Window
      BufferedImage image = new BufferedImage(800,600,BufferedImage.TYPE_INT_RGB);
      Graphics2D gdd = image.createGraphics();
      MediaTracker tracker = new MediaTracker(this);
      Image bground = getToolkit().getImage("MajorityRule.jpg"),
            bawl = getToolkit().getImage("bawl.gif");
      RenderScreen rScreen = new RenderScreen(this);
      BufferStrategy strategy;
      Graphics g;
      Rectangle rect = new Rectangle(400,0,150,150);
      //Game game = new Game();
      public void renderView()
        g = strategy.getDrawGraphics();
        //--------- Game Procedures [start]
        gdd.drawImage(bground,0,0,this);
        gdd.drawString("fps: ["+rScreen.fps+"] Cycle Time: ["+rScreen.cycTime+"]",0,10);
        //--------- Game Procedures [end]
        //---------test
        gdd.drawImage(bawl,rect.x,rect.y,rect.width,rect.height,this);
        rect.translate(0,1);
        g.drawImage(image,0,0,this);
        //g.dispose();
        strategy.show();
      public Screen(JFrame frame)
        super(frame);
        try
          tracker.addImage(bground,0);
          tracker.addImage(bawl,1);
          tracker.waitForAll();
        catch(InterruptedException ie){ ie.printStackTrace(); }
        setBackground(Color.black);
        setForeground(Color.white);
    import java.awt.*;
    import java.awt.event.*;
    import javax.swing.*;
    public class MajorityRule extends JFrame
      // Graphic System Handlers
      GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
      GraphicsDevice gd = ge.getDefaultScreenDevice();
      GraphicsConfiguration gc = gd.getDefaultConfiguration();
      Screen screen = new Screen(this);
      Paper paper = new Paper();
      public void windowed()
        paper.setSize(getWidth(),getHeight());
        getContentPane().add(paper);
        setResizable(false);
        setVisible(true);
      public void fullscreen()
        DisplayMode dMode = new DisplayMode(800,600,32,200);
        screen.setBounds(0,0,800,600);
        if (gd.isFullScreenSupported()) gd.setFullScreenWindow(screen);
        if (gd.isDisplayChangeSupported()){ gd.setDisplayMode(dMode); };
        screen.setIgnoreRepaint(true);
        screen.setVisible(true);
        screen.rScreen.setPriority(Thread.MAX_PRIORITY);
        screen.rScreen.start();
        screen.requestFocus();
      public MajorityRule(String args[])
        setTitle("Majority Rule [Testing Block]");
        setBounds(0,0,410,360);
        setDefaultCloseOperation(EXIT_ON_CLOSE);
        getContentPane().setLayout(null);
        if (args.length > 0 && args[0].equals("-window")) windowed();
        else fullscreen();
      public static void main(String args[])
        new MajorityRule(args);
    };

  • Event handling in Dynpage

    Hi all,
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    Appreciate you help.
    Thanks,
    Karthik

    Hi,
    The following code regarding Event Handling for Dynpage. May be this example code useful for you.
    package com.customer.training;
    import com.sapportals.htmlb.Button;
    import com.sapportals.htmlb.Component;
    import com.sapportals.htmlb.DropdownListBox;
    import com.sapportals.htmlb.Form;
    import com.sapportals.htmlb.FormLayout;
    import com.sapportals.htmlb.GridLayout;
    import com.sapportals.htmlb.InputField;
    import com.sapportals.htmlb.Label;
    import com.sapportals.htmlb.TextView;
    import com.sapportals.htmlb.enum.ButtonDesign;
    import com.sapportals.htmlb.enum.TextViewDesign;
    import com.sapportals.htmlb.event.Event;
    import com.sapportals.htmlb.page.DynPage;
    import com.sapportals.htmlb.page.PageException;
    import com.sapportals.htmlb.rendering.IPageContext;
    import com.sapportals.portal.htmlb.page.PageProcessorComponent;
    public class Suresh_SearchDynPage extends PageProcessorComponent {
      public DynPage getPage() {
        return new Suresh_SearchDynPageDynPage();
      public static class Suresh_SearchDynPageDynPage extends DynPage {
         public int flag ;
         public final static int disp_info = 1;
         public final static int read_info = 2;
         public final static int error_info = 3;
         public static String flag_info = "MyFlag";
         public static String disp_drop = " ";
         public String errorMessage;
           String firstName ;
           String lastName ;
           String Email ;
           String dropsel;
    Initialization code executed once per user.
        public void doInitialization() {
                        flag = read_info;          
                        IPageContext ctx = this.getPageContext();
                        ctx.setAttribute("FirstName","");
                        ctx.setAttribute("LastName","");
                        ctx.setAttribute("email","");     
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        public void doProcessAfterInput() throws PageException {
              Component comp;
              comp = this.getComponentByName("FirstName");
              if (comp instanceof InputField)
                        firstName = ((InputField) comp).getString().getValue();
              comp = this.getComponentByName("LastName");
              if (comp instanceof InputField)
                                  lastName = ((InputField) comp).getString().getValue();
              comp = this.getComponentByName("email");
                        if (comp instanceof InputField)
                                            Email = ((InputField) comp).getString().getValue();
              comp = this.getComponentByName("DisplayType");
                        if (comp instanceof DropdownListBox)
                             dropsel = ((DropdownListBox) comp).getSelection();          
    // Store the selected values in corresponding field name for nextScreen                         
              IPageContext ctx = this.getPageContext();
              flag = new Integer(ctx.getAttribute(flag_info).toString()).intValue();
              ctx.setAttribute("FirstName",firstName);
              ctx.setAttribute("LastName",lastName);
              ctx.setAttribute("email",Email);
              ctx.setAttribute("DisplayName",dropsel);                                   
    Create output. Called once per request.
        public void doProcessBeforeOutput() throws PageException {
          Form myForm = this.getForm();
           this.getPageContext().setAttribute(flag_info,new Integer(flag));
         switch(flag)
          case read_info:
                    FormLayout f1 = new FormLayout();
                    TextView t1 = new TextView();
                    t1.setDesign(TextViewDesign.HEADER2);
                    t1.setText("This is the Info U Entered................");
                    TextView t2 = new TextView();
                    t2.setText(firstName);
                    Label dispFname = new Label("dispFirstName");
                    dispFname.setText("First Name");
                    dispFname.setLabelFor(t2);
                    TextView t3 = new TextView();
                    t3.setText(lastName);
                    Label dispLname = new Label("dispLastName");
                    dispLname.setText("Last Name");
                    dispLname.setLabelFor(t3);
                    TextView t4 = new TextView();
                    t4.setText(Email);
                    Label dispEmail = new Label("dispEmail");
                    dispEmail.setText("Email");
                    dispEmail.setLabelFor(t4);
                    TextView t5 = new TextView();
                    t5.setText(dropsel);
                    Label dispType = new Label("dispInfo");
                    dispType.setText("Display Info");
                    dispType.setLabelFor(t5);
                    Button btnback = new Button("Back");
                    btnback.setText("Back");
                    btnback.setOnClick("Back");
                    f1.addComponent(1,1,t1);
                    f1.addComponent(2,1,dispFname);
                    f1.addComponent(2,2,t2);
                    f1.addComponent(3,1,dispLname);
                    f1.addComponent(3,2,t3);
                    f1.addComponent(4,1,dispEmail);
                    f1.addComponent(4,2,t4);
                    f1.addComponent(5,1,dispType);
                    f1.addComponent(5,2,t5);
                    f1.addComponent(6,1,btnback);
                    myForm.addComponent(f1);
               break;
          case error_info:
                    FormLayout f2 = new FormLayout();
                    IPageContext ctx = this.getPageContext();
                    TextView t6 = new TextView();
                    t6.setText("Error : ");
                    t6.setDesign(TextViewDesign.HEADER2);
                    t6.setText(errorMessage);
                    f2.addComponent(3,1,t6);
                    myForm.addComponent(f2);
               break;
                default:
                              // create your GUI here....
                                        GridLayout g1 = new GridLayout();
    //                                    IPageContext ctx1 = this.getPageContext();
                                        Label first_l = new Label("First Name");
                                        InputField first_if = new InputField("FirstName");
                                        Label last_l  =  new Label("Last Name");
                                        InputField last_if = new InputField("LastName");
                                        Label email_l = new Label("E-Mail Address");
                                        InputField email_if = new InputField("email");
                                        Label info_l = new Label("Display Info for");
                                        DropdownListBox displayType = new DropdownListBox("DisplayType");
                                        displayType.addItem("userinfo", "User Info");
                                        displayType.addItem("groupinfo", "Group Membership");
                                        displayType.addItem("roleinfo", "Role Assignment");     
    //                                    displayType.setSelection(ctx1.getAttribute("DisplayType").toString());
                                        Button btn = new Button("submit");            
                                        btn.setText("Get Info");
                                        btn.setDesign(ButtonDesign.EMPHASIZED);
                                        btn.setOnClick("Get");
    //                                    add the ui controls to grid
                                        g1.setCellPadding(4);
                                        g1.addComponent(1,1,first_l);
                                        g1.addComponent(1,2,first_if);
                                        g1.addComponent(2,1,last_l);
                                        g1.addComponent(2,2,last_if);
                                        g1.addComponent(3,1,email_l);
                                        g1.addComponent(3,2,email_if);
                                        g1.addComponent(4,1,info_l);
                                        g1.addComponent(4,2,displayType);
                                        g1.addColSpanComponent(5,1,btn,2);
                                        g1.setHeightPercentage(50);
                                        g1.setColumnSize(50);
                                        myForm.setFocusedControl(displayType);
                                        myForm.setMessageBarAtFormEnd(true);
                                        myForm.setWidthInHundredPercent(true);
                                        myForm.addComponent(g1);     
                                        break;
        public void onGet(Event e)
         if(firstName.length()== 0)
              flag = error_info;
              errorMessage = "Invalid Input..............";
         else
              flag = read_info;
          public void onBack(Event e1)
                flag = disp_info;

  • Event handling in custom Non-GUI components

    I have a class which needs to fire events to outside. These events maybe captured by several objects in outside world. How can I achieve this? In so many places I read, they always refer to AWT and Swing whereas my objects don't have any dependency to GUI.
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    I have experience in .Net programming with Events and Delegates (function pointers), but cannot find something like that in Java. All it offers is various kinds of GUI related Listeners where I can't find a proper help resource using them in Non-GUI components.

    ravinsp wrote:
    I have a class which needs to fire events to outside. These events maybe captured by several objects in outside world. How can I achieve this? In so many places I read, they always refer to AWT and Swing whereas my objects don't have any dependency to GUI.
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    MyEvent someEvent = new MyEvent();
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  • Bug: RichTextEditor "Initialize" not classed as event handler

    I'm trying to load the RichTextEditor control in a popup window. Here's my code:
    var rte:RichTextEditor = new RichTextEditor();
    rte.width   =  600;
    rte.height  =  500;
    rte.title   =  'Edit Text';
    I need to add the initialize event handler so I can add a button to the toolbar (as per the example on the Adobe website).
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    Compare this with:
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    Can anyone else confirm whether this is a bug with the SDK or not? I can simply add the button outside of the RTE for now, but then I'd have to wrap the RTE in a separate panel to accomodate the button, which isn't ideal.
    Thanks in advance.

    Hi,
    this is how to add the event listener
    rte.addEventListener(FlexEvent.INITIALIZE,addSaveButton);
    David.

  • Button Event Handler in a JList, Please help.

    Hi everyone,
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              //return;
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              System.out.println("VALUE: "+comp.toString());
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    I have yet to find an example on the web, using Google, that demonstrated using buttons inside a JList.
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    A renderer is not a component, so you can't click on it. A renderer is just used to paint a representation of a component at a certain position in your JList.
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    b) Or maybe like windows explorer. Select the items in the list and then use a JPopupMenu to perform the desired functionality.
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  • How to add event handling for a menu?

    hi,
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    it was like this
    menuItem = new JMenuItem("Exit",KeyEvent.VK_X);
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    menuItem.addActionListener(this);
    menu.add(menuItem);
         public void actionPerformed(ActionEvent e)
    JMenuItem source = (JMenuItem)(e.getSource());
    String s = "Action event detected. Event source: " + source.getText();
    System.out.println(s);     
    public void itemStateChanged(ItemEvent e)
    JMenuItem source = (JMenuItem)(e.getSource());
    String s = "Item event detected. Event source: " + source.getText();
    System.out.println(s);
    now int he second menu i don't have any menu item and i want to do the event handling for the menu itself. any ideas how to do it. following is the code for the menu
    //Build the second menu.
    menu2 = new JMenu("Options");
    menu2.setMnemonic(KeyEvent.VK_O);
    menuBar.add(menu2);
    menu2.addActionListener(this);     //this does nto work

    You were on the right track. However, selecting a menu is different from selecting a menu item. MenuItem chucks an ActionEvent and Menu will send an ItemEvent.
    If you pile all action output to one actionPerformed method then be careful of your assumptions on what the source type will be. If by any chance the Menu has sent an ActinoEvent then your code will have caused a ClassCastException.
    import java.awt.*;
    import java.awt.event.*;
    import javax.swing.*;
    public class MenuTest implements ActionListener, ItemListener {
        JMenuItem menuItem;
        JMenu menu1, menu2;
        JMenuBar menubar;
        JFrame frame;
        public MenuTest() {
            frame = new JFrame("MenuTest");
            frame.setDefaultCloseOperation(frame.EXIT_ON_CLOSE);
            menubar = new JMenuBar();
            frame.setJMenuBar(menubar);
            menu1 = new JMenu("File");
            menu1.setMnemonic(KeyEvent.VK_F);
            menuItem = new JMenuItem("Exit",KeyEvent.VK_X);
            menuItem.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_X, ActionEvent.ALT_MASK));
            menuItem.addActionListener(this);
            menu1.addItemListener(this);
            menu1.add(menuItem);
            menubar.add(menu1);
            //Build the second menu.
            menu2 = new JMenu("Options");
            menu2.setMnemonic(KeyEvent.VK_O);
            menu2.addActionListener(this); //this does not work
            menu2.addItemListener(this); // use this instead
            menubar.add(menu2);
            JPanel panel = new JPanel();
            panel.setPreferredSize(new Dimension(100,100));
            frame.getContentPane().add(panel);
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    Best regards,
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