How to setup auto paddle & constant speed for ball

Question

I wanted to setup an automatic paddle so that this game will works as a one-player game. I have 3 files here. Ball.java, Play.java and pong.java.
My code below doesn't seem to get the paddle moving at all. How can I do so? What's my mistake or how should I do it correctly?
Pls help....:(
Also the ball runs faster and faster after each volley and the ball deflects at a smaller x-axis angle after hitting the rightWall & leftWall. How can I get a constant velocity as well as a more balance deflection??
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Toolkit;
import java.awt.event.ItemEvent;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionListener;
import java.awt.geom.Rectangle2D;
import javax.swing.JButton;
import javax.swing.Timer;
import javax.swing.JPanel;
import java.awt.*;
import java.awt.event.*;
class Play extends JPanel implements ActionListener, MouseMotionListener, ItemListener {
     private double maxX,maxY,y; // dimensions of the surface of play
     private double heightP,widthP,semiWidthP; // dimensions of the paddle
     double thickness = 10; // thickness of the walls, ceiling and floor
     private Toolkit tk;
     private Ball ball; // graphic objects
     private Rectangle2D user_paddle,computer_paddle, leftWall, rightWall, exitA, exitB;
     private Timer timer; // objects of interaction
     private JButton button, reset;
     private int countA, countB;
     int computer ;
     int user;
     TextField userscore = new TextField(4);
     TextField compscore = new TextField(4);
     Thread t = null;
     Play(Ball ball,Timer timer,JButton button, JButton reset) {
          this.ball=ball;
          this.timer=timer;
          this.button=button;
          this.reset=reset;
          userscore.setEditable(false);
          compscore.setEditable(false);
          // dimensions of the applet
          this.maxX = getSize().width;
          this.maxY = getSize().height;
          tk = getToolkit();
          // paddle
          semiWidthP = ball.getDiametre()/2;
          widthP=semiWidthP*2;
          heightP = 50;
          user_paddle = new Rectangle2D.Double((maxX-thickness-heightP)*0.05,(maxY)/4,
          semiWidthP,heightP);
          computer_paddle = new Rectangle2D.Double((maxX-thickness-heightP)*1.03,(maxY)/4,
          semiWidthP,heightP);
          // borders
          exitA = new Rectangle2D.Double(0,0,thickness,maxY);
          exitB = new Rectangle2D.Double(maxX-thickness,0,thickness,maxY);
          rightWall = new Rectangle2D.Double(0,0,maxX,thickness);
          leftWall = new Rectangle2D.Double(0,maxY-thickness,maxX,thickness);
          // to indicate that the movements of the mouse will be listened to
          addMouseMotionListener(this);
     }//end of Play
     // to adjust the graphic objects if the play changed dimension
     public void updateWall() {
          double maxX=getSize().width, maxY=getSize().height;
          if(this.maxX!=maxX ||this.maxY!=maxY){
               this.maxX=maxX;
               this.maxY=maxY;
               user_paddle.setFrame((maxX-thickness-heightP)*0.05,(maxY)/4,semiWidthP,heightP);
               //computer_paddle.setFrame((maxX-thickness-heightP)*1.03,(maxY)/4,semiWidthP,heightP);
               exitA.setFrame(0,0,thickness,maxY);
               exitB.setFrame(maxX-thickness,0,thickness,maxY);
               rightWall.setFrame(0,0,maxX,thickness);
               leftWall.setFrame(0,maxY-thickness,maxX,thickness);
     }//end of UpdateWall
     // posting of the contents of the screen
     public void paintComponent (Graphics g) {
          super.paintComponent(g);
          Graphics2D g2D = (Graphics2D)g;
          updateWall();
          paintPad(y);
          //g2D.drawString(ball.getX()+","+ball.getY(),10,15);
          g2D.drawString("Player A: "+ countA,10,20);// drawString update scores
          g2D.drawString("Player B: "+countB,500,20);
          g2D.fill(exitA); g2D.fill(exitB);
          g2D.fill(rightWall);
          g2D.fill(leftWall);
          g2D.setColor(Color.blue);
          ball.toPost(g2D);
          g2D.setColor(Color.red);
          g2D.fill(user_paddle);
          //g2D.fill(computer_paddle);
          g2D.setColor(Color.gray);
          g2D.drawLine(300,0,300,400);
          while( t!=null) {
               try     {
                    t.sleep(10);
               catch(InterruptedException e) {}
     }//end of paintComponent
     private void bip(){
          tk.beep();
     public void itemStateChanged(ItemEvent ev) {
               Object sc = ev.getSource();
               boolean on =ev.getStateChange()== ItemEvent.SELECTED;
     //treatment of the Action Vents of Timer
     public void actionPerformed(ActionEvent e) {
          double dx = ball.getDx();
          double dy = ball.getDy();
          // to move the ball//
          ball.toGoA(ball.getX()+ball.getDx(),ball.getY()+ball.getDy());
          // checking of a change of direction (with acceleration...)
          if(ball.intersects(leftWall) || ball.intersects(rightWall)){ // striking with dimensions
               ball.setDy(dy>0 ? -(++dy) : -(--dy));
               bip();
          else if((ball.intersects(user_paddle)) || (ball.intersects(computer_paddle))){
               ball.setDx(dx>0 ? -(++dx) : -(--dx));
               bip();
          else if((ball.intersects(leftWall)||ball.intersects(user_paddle)) || (ball.intersects(leftWall)||ball.intersects(computer_paddle))){
               ball.setDx(dx>0 ? -(++dx) : -(--dx));
               bip();
          else if((ball.intersects(rightWall)||ball.intersects(user_paddle))||(ball.intersects(rightWall)||ball.intersects(computer_paddle))){
               ball.setDx(dx>0 ? -(++dx) : -(--dx));
               bip();
          else if(ball.intersects(exitA)){
               ball.toHide();
               button.setText("Start");
               timer.stop();
               ++user;
               paintC(computer, user);
               //++countB;
          else if(ball.intersects(exitB)){
               ball.toHide();
               button.setText("Start");
               timer.stop();
               ++computer;
               paintC(computer, user);
               //++countA;
          paintPad(dy);
          repaint();
     }//end of actionPerformed
     public void setTextFields(TextField c1, TextField c2) {
          compscore=c1;
          userscore=c2;
     public void paintC(int computer, int user) {
          compscore.setText( " " + computer );
          userscore.setText( " " + user );
          compscore.repaint();
          userscore.repaint();
     public void paintPad(double y){
          computer_paddle.setFrame((maxX-thickness-heightP)*1.03,y-semiWidthP,semiWidthP,heightP);
          while( t!=null) {
               try     {
               t.sleep(10);
               catch(InterruptedException e) {}
          //computer_paddle.setFrame(computer_paddle.getX(),dy-semiWidthP,semiWidthP,heightP);
          repaint();
     // draft displacements of mouse
     public void mouseDragged(MouseEvent ev){// ignore
     public void mouseMoved(MouseEvent ev){
     // replace X by making sure that one remains in the terminals of the applet
          double dy = ball.getDy();
          double px = Math.min(maxY-thickness,
          Math.max(ev.getY(),semiWidthP+thickness));
          user_paddle.setFrame(user_paddle.getX(),px-semiWidthP,semiWidthP,heightP);
          repaint();
}

Answer 1

Hi,
For creating the deliveries automatically you can use the T.code VL04 in the b/g or run the program RV50SBT1 in the b/g every 2 hours. This can be done using T.code SM36, this is where you set up the job. Here you can specify the details and the timing.
For creating the TO's for the delivery, either you do it through the config setting or run a similar job in the b/g and TO's should be created automatically.
For some reason if you find deliveries are not created you may use V.22 and give the Log number(which you will get from the job log) and see the reasons for delivery not being created.
hope this helps.