このJavaプログラム(WWWブラウザ内で動作するものは「アプレット」と言います) の場合、たとえば下のようなプログラムとして記述して、これをJavaコンパイラ というツールで変換して作成します。

import java.awt.*;
import java.applet.*;
import java.util.*;
import java.net.*;

public class koushin extends Applet implements Runnable {
    Image imgs[];
    int nimgs = 14;
    int imgwidth;
    int x, newx;
    int dist = 5;
    int timeout = 200;
    Thread scroller;

    public void init() {
        newx = x = size().width;
        imgs = new Image[nimgs];
        for (int i = 0 ; i < nimgs ; i++) {
            imgs[i] = getImage(getDocumentBase(), "GIF/B" + (i+1) + ".GIF");
        }
        setBackground(Color.black);
    }
    public void start() {
        if (scroller == null) {
            scroller = new Thread(this);
            scroller.start();
        }
    }
    public void stop() {
        if (scroller != null) {
            scroller.stop();
            scroller = null;
        }
    }
    public void run() {
        while (true) {
        try {Thread.currentThread().sleep(timeout);} catch (InterruptedException e){}
            scroll(dist);
        }
    }
    synchronized void scroll(int dist) {
        newx += dist;
        repaint();
    }
    public void update(Graphics g) {
      if (newx != x) {
            int dist = newx - x;
            if (dist > 0) {
                g.copyArea(1, 1, (size().width-2) - dist, size().height-2, dist, 0);
                for (x = newx ; x > size().width ; x -= Math.max(size().width - 2, imgwidth));
                paint(g, 1, dist + 1);
            } else {
                g.copyArea(1 - dist, 1, (size().width-2) + dist, size().height-2, dist, 0);
                for (x = newx ; x < 0 ; x += Math.max(size().width - 2, imgwidth));
                paint(g, (size().width-1) + dist, size().width-1);
            }
        } else {
            paint(g);
        }
    }
    public boolean imageUpdate(Image img, int flags, int x, int y, int w, int h) {
        if ((flags & WIDTH) != 0) {
            imgwidth += img.getWidth(this);
        }
        return super.imageUpdate(img, flags, x, y, w, h);
    }
    public void paint(Graphics g, int fromx, int tox) {
        int x = this.x;
        newx = x;
        g.setColor(Color.black);
        g.fillRect(fromx, 1, tox - fromx, size().height-2);
        g.clipRect(fromx, 1, tox - fromx, size().height-2);
        g.setColor(Color.black);
        for (int i = 0 ; i < nimgs ; i++) {
            if (imgs[i] == null) {
                continue;
            }
            int w = imgs[i].getWidth(this);
            int h = imgs[i].getHeight(this);
            if ((w > 0) && (h > 0)) {
                if ((x + w > fromx) && (x < tox)) {
                    g.drawImage(imgs[i], x, size().height - (h+10), this);
                }
                if ((x + w) > size().width) {
                    x -= Math.max(size().width - 2, imgwidth);
                    if ((x + w > fromx) && (x < tox)) {
                        g.drawImage(imgs[i], x, size().height - (h+10), this);
                    }
                }
                x += w;
            }
        }
    }
    public void paint(Graphics g) {
        g.draw3DRect(0, 0, size().width, size().height, true);
        paint(g, 1, size().width-1);
    }
}

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