Anybody who wants to moderate an IO working program - come on do it

Question

It just works -- help to improvr
run it first then try to understand
The project is to be submitted before april 15th - I discovered java around August last year
My programing background only Pascal - 4 years ago
For a novice - I'm really good....in getting results... not in clean programming...sorry
// legend
//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ will mean a new file, another file or the end of the file
//^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ will mean read this instruction
// ok lets go
//^^^^^^^^^ The following code is written in notepad and saved as test.bat
// this file can be saved in jdk/bin as test.bat
//~~~~~~~~~ begin file > test.bat
keytool -delete -alias mykey -keystore "C:\Program Files\JavaSoft\JRE\1.3.1\lib\security/cacerts" -storepass changeit
javac newoscillo13.java
jar cvf myoscillo.jar newoscillo13.class
del c:\windows\.keystore
keytool -genkey -alias mykey -keypass tarachand -dname "cn=test" -storepass tarachand
jarsigner -signedjar hellosigned.jar -storepass tarachand myoscillo.jar mykey
keytool -export -alias mykey -file mykey.cer -storepass tarachand
keytool -import -file mykey.cer -keystore "C:\Program Files\JavaSoft\JRE\1.3.1\lib\security/cacerts" -storepass changeit
del newoscillo13.class
//~~~~~~~~~ end file > test.bat
//^^^^^^^^^ save the following file as datafile.txt in jdk/bin
//~~~~~~~~~ begin file > datafile.txt this file consists of data ranging from 0 to 300
140 162 340 45 300 300 60 200 20 300
100 16 2 45 300 3 50 64 250 220     
100 360 20 390 40 50 25 10 0 294
230 200 309 140 162 310 45 300 300 60 200 20
//~~~~~~~~~ end file > more data must be added I've given u just this few
//^^^^^ Heres the main program. save it as newoscillo13.java in jdk/bin
//~~~~~~~~~~ begin newoscillo13.java
import java.awt.*;
import java.awt.Graphics;
import java.applet.Applet;
import java.util.*;
import java.lang.*;
import java.text.*;
import java.io.*;
public class newoscillo13 extends Applet implements Runnable {
     Thread timer;// thread to produce a delay before repainting
     int delay = 1000;// delay between readings in ms
     boolean initialiser = true;
     String[] nowdate = new String[13];
// defining the oscilloscope coordinates variables
     int screentop = 36;// where the oscillo grid starts
     int screenright = 55; // where the oscillo grid starts
     int screenheight = 400; // size of oscillo
     int screenwidth = 480;// size of oscillo
     int numofcolumns = 12;
     int numofrows = 10;
     int rowheight = screenheight/numofrows;
     int grid = screenwidth/(numofcolumns*5); // grid size
     int numofpoints = 61;
     int[] measuredval = new int[numofpoints +1]; // this array will contain the points to display on the oscillo
     int originx = screenright; // pixel coordinates 5
     int originy = (screentop+screenheight/2);// pixel coordinates 2 + 320/2 = 162
     int xmax = screenright + screenwidth;
     int ymax = screentop + screenheight;
     Color lineColor = Color.white;
     Color gridColor = Color.red;
     Color oscilloBgnd = Color.blue;
     Color fontColor = Color.black;
     Color borderColor = Color.red;
     Color measuredvaldispbgnd = Color.green;
// start programing
     public void init() { }
// starting paint
     public void paint(Graphics g){
     setBackground(Color.white);
     g.setColor(borderColor);
     g.fillRect(screenright-3,screentop-3,screenwidth+6,screenheight+6);
     g.setColor(oscilloBgnd);
     g.fillRect(screenright,screentop,screenwidth,screenheight);
     g.setColor(gridColor);
     g.drawLine(screenright,screentop+screenheight/2,screenright+screenwidth,screentop+screenheight/2);
     g.drawLine(screenright+screenwidth/2,screentop,screenright+screenwidth/2,screentop+screenheight);
     for (int i=screenright; i< screenright+screenwidth+1; i= i+grid*5) {
     g.drawLine(i,screentop,i,screentop+screenheight);}//vertical lines on oscillograph
     for (int i=screenright; i< screenright+screenwidth+1; i= i+grid) {
     g.drawLine(i,screentop+screenheight/2-5,i,screentop+screenheight/2+5);}
     for (int i=screentop; i< screentop+screenheight+1; i= i+screenheight/10) {
     g.drawLine(screenright,i,screenright+screenwidth,i);}// horizon lines on oscillograph
     for (int i=screentop; i< screentop+screenheight+1; i= i+screenheight/50) {
     g.drawLine(screenright+(screenwidth/2)-5,i,screenright+(screenwidth/2)+5,i);}
// reading a text file > datafile.text placed in c:\jdk1.3.1\bin
int [] measuredval = new int[numofpoints +1];     
int measuredvalue;
try {
RandomAccessFile f = new RandomAccessFile ("c:\\jdk1.3.1\\bin\\datafile.txt", "r");
int dataarraysize = 0;
String s;
          while ( (s=f.readLine()) != null )                          {
               StringTokenizer st = new StringTokenizer(s);
                              while (st.hasMoreTokens()) {
                    measuredvalue = Integer.parseInt(st.nextToken());
                    if (dataarraysize < numofpoints +1) measuredval[dataarraysize] = measuredvalue;
                    if (dataarraysize>numofpoints) {
                    measuredval[numofpoints] = measuredvalue;
                    for (int k =1; k <= (numofpoints -1); k++) measuredval[k] = measuredval[k+1];
                    dataarraysize++;
                         }     // end while
                         }     // end try
catch (Exception e) {System.out.println("Execption in constructor readertext13: "+e); } // end catch
               for (int a = 0;a<=(numofpoints -1);a++){
               if (measuredval[a] < 0) measuredval[a] = 0;
               if (measuredval[a] > screenheight) measuredval[a] = screenheight;
               //System.out.println(""+measuredval[a]);
// display date and temperature horizontally below the oscilloscope
     SimpleDateFormat now1 = new SimpleDateFormat("dd-MM-yyyy hh:mm:ss");
     Date now = new Date();
     String nowstring = now1.format(now);
     g.setColor(measuredvaldispbgnd);
     g.fillRect(screenright - 4,ymax+5+40,screenwidth+8,20);
     int val = measuredval[numofpoints-1];
     g.setColor(fontColor);
     g.drawString(""+nowstring +" Temperature = "+val+"�C", screenright+10,ymax + 20+40);
// x axis labelling - temporary
SimpleDateFormat axisdate = new SimpleDateFormat("mm:ss");
Date noww = new Date();
while (initialiser) {
for (int ii = 0; ii<13;ii++) nowdate[ii] = axisdate.format(noww);
initialiser = false;}
//---------------888888888888888
// labelling x axis - time for each column
for (int nw = 0;nw<12;nw++){
nowdate[nw] = nowdate[nw + 1]; }
nowdate[12] = axisdate.format(now);
int wn = 0;
while (wn <12) {
g.drawString(nowdate[wn], screenright wn*40 - 17 ,screentopscreenheight+20);
g.drawString(nowdate[wn+1], screenright +(wn+1)*40-17 ,screentop+screenheight+20);
wn = wn +2;}
g.drawString(nowdate[12], screenright + numofcolumns*40-17 ,screentop+screenheight+20);
// label y axis
     //labeling vertical axis
     g.setColor(fontColor);
     for (int n = 0;n<11;n++) {
     int gridlabel = (screenheight - n*40);
     g.drawString(""+gridlabel+"�C", screenright - 45,screentop+screenheight*n/10 +4);
// title label
     g.setColor(measuredvaldispbgnd);
     g.fillRect(screenright-3,5,screenwidth+5,20);
     g.setColor(fontColor);
     g.drawString("Graph of temperature measured against time at which it was measured", screenright+7, 18);
// end label axes
     // draw another graphic , vertical display
     g.setColor(Color.gray);
     g.fillRect(xmax+10,screentop,16,screenheight+4 );
     g.setColor(gridColor);
     g.fillRect(xmax+12,screentop+2,12,screenheight);
     // above are fixed rectangles below is a pulsating rectangle depending on val
     g.setColor(oscilloBgnd);
     int zerotemp = screentop + screenheight + 2;
     int temperature = screenheight - val;
     g.fillRect(xmax+12,screentop+2,12,temperature);
// end draw another graphic--------------------------------------------------------------
// graphic display of temperature -- this is most important, the movie
     originx = screenright;
     originy = screentop + screenheight - measuredval[0];
// draw 10 line segments     
     for (int i = 1; i <= (numofpoints -1);i++){
     g.setColor(lineColor);
     g.drawLine(originx,originy,originx+grid,screentop + screenheight - measuredval);
// the starting point is originx, originy
// the lowest point of the oscillograph is taken as 0, so screentop + screenheight
// the end point of the line is originx+grid,screentop + screenheight - measuredval[i]
// the above coordinates become the next starting point
     originx = originx+grid;
     originy = screentop + screenheight - measuredval[i];
// ending paint
public void destroy() {  }
public void start() {
timer = new Thread(this);
timer.start();
public void stop() {
timer = null;
public void run() {
Thread me = Thread.currentThread();
while (timer == me) {
try {
Thread.currentThread().sleep(delay);// wait for delay ms
} catch (InterruptedException e) {
System.out.println("Exception in method run: "+e);
repaint();
// start update to avoid flickering of the image
private Image offScreenImage;
private Dimension offScreenSize;
private Graphics offScreenGraphics;
public final synchronized void update (Graphics g) {
Dimension d = getSize();
if((offScreenImage == null) || (d.width != offScreenSize.width) || (d.height != offScreenSize.height))
offScreenImage = createImage(d.width, d.height);
offScreenSize = d;
offScreenGraphics = offScreenImage.getGraphics();
offScreenGraphics.clearRect(0, 0, d.width, d.height);
paint(offScreenGraphics);
g.drawImage(offScreenImage, 0, 0, null); }
// end update ton avoid flickering
}// end applet
//~~~~~~~~~~ end newoscillo13.java
//^^^^^^^^^ now the html part
//~~~~~~~~~ save as newoscillo13.html
<HTML><BODY>
<OBJECT classid="clsid:CAFEEFAC-0013-0001-0000-ABCDEFFEDCBA"
codebase="http://java.sun.com/products/plugin/1.3.1/jinstall-131-win32.cab#Version=1,3,1,0" WIDTH=600 HEIGHT=600>
<PARAM NAME = CODE VALUE = newoscillo13 >
<PARAM NAME = ARCHIVE VALUE ="hellosigned.jar" >
<PARAM NAME="type" VALUE="application/x-java-applet;jpi-version=1.3.1">
</OBJECT>
</BODY></HTML>
//~~~~~~~~~ save as newoscillo13.html in jdk/bin
//^^^^^^^^^ go to dos > go to C:\jdk1.3.1\bin>
//^^^^^^^^^ type test and then enter
//^^^^^^^^^ wait to type yes and then enter
// go back to windows, make sure java plug in advanced tab has c:\program files\javasoft\jre1.31
now you can execute the html file newoscillo13.html and please it would be fantastic to
send me your comments and suggestions to improve the program.
I'm suzanne available at [email protected]

Answer 1

Here are my suggestions:
1) Get rid of the signing stuff -- you don't need it if you make the changes as I documented in the code posted below. Java applet can read any data file as long as the files are kept under the same document or code base -- notice that filename is specified without a path (i.e., it's relative). This makes it easier to deploy on the web
2) Since you do not need to sign the applet, you don't need to create a jar file.
3) Since you are not using anything special like swing, use the modified HTML shown below and you'll not have to worry about downloading Java plugin because the modified code will work with IE's native JVM version 1.1.4 and NN's native JVM version 1.1.5 -- should you make additions to the code, make sure that you're not calling methods implemented by Sun after the versions described.
If this helps, give me the Dukes.... If you have more questions, ask!
V.V.
PS: The changes have been tested with the appletviewer, IE5, IE5.5, NN4.79 and NN6.2
HTML
======
<HTML><BODY>
<APPLET CODE="newoscillo13.class" CODEBASE="." width=600 height=600></APPLET>
</BODY></HTML>
JAVA FILE
========
import java.awt.*;
import java.awt.Graphics;
import java.applet.Applet;
import java.util.*;
import java.lang.*;
import java.text.*;
import java.io.*;
import java.net.*;        //<---------- V.V.
public class newoscillo13 extends Applet implements Runnable {
   Thread timer;
   // thread to produce a delay before repainting
   int delay = 1000;
   // delay between readings in ms
   boolean initialiser = true;
   String[] nowdate = new String[13];
   // defining the oscilloscope coordinates variables
   int screentop = 36;
   // where the oscillo grid starts
   int screenright = 55;
   // where the oscillo grid starts
   int screenheight = 400;
   // size of oscillo
   int screenwidth = 480;
   // size of oscillo
   int numofcolumns = 12;
   int numofrows = 10;
   int rowheight = screenheight/numofrows;
   int grid = screenwidth/(numofcolumns*5);
   // grid size
   int numofpoints = 61;
   int[] measuredval = new int[numofpoints +1];
   // this array will contain the points to display on the oscillo
   int originx = screenright;
   // pixel coordinates 5
   int originy = (screentop+screenheight/2);
   // pixel coordinates 2 + 320/2 = 162
   int xmax = screenright +
      screenwidth;
   int ymax = screentop +
      screenheight;
   Color lineColor = Color.white;
   Color gridColor = Color.red;
   Color oscilloBgnd = Color.blue;
   Color fontColor = Color.black;
   Color borderColor = Color.red;
   Color measuredvaldispbgnd = Color.green;
   // start programing
   private URL Codebase;     //<---------- V.V.
   public void init() {
      Codebase=getCodeBase();     //<---------- V.V.
   // starting paint
   public void paint(Graphics g) {
      setBackground(Color.white);
      g.setColor(borderColor);
      g.fillRect(screenright-3,screentop-3,screenwidth+6,screenheight+6);
      g.setColor(oscilloBgnd);
      g.fillRect(screenright,screentop,screenwidth,screenheight);
      g.setColor(gridColor);
      g.drawLine(screenright,screentop+screenheight/2,screenright+screenwidth,screentop+screenheight/2);
      g.drawLine(screenright+screenwidth/2,screentop,screenright+screenwidth/2,screentop+screenheight);
      for (int i=screenright; i< screenright+screenwidth+1; i= i+grid*5) {
         g.drawLine(i,screentop,i,screentop+screenheight);
      //vertical lines on oscillograph
      for (int i=screenright; i< screenright+screenwidth+1; i= i+grid) {
         g.drawLine(i,screentop+screenheight/2-5,i,screentop+screenheight/2+5);
      for (int i=screentop; i< screentop+screenheight+1; i= i+screenheight/10) {
         g.drawLine(screenright,i,screenright+screenwidth,i);
      // horizon lines on oscillograph
      for (int i=screentop; i< screentop+screenheight+1; i= i+screenheight/50) {
         g.drawLine(screenright+(screenwidth/2)-5,i,screenright+(screenwidth/2)+5,i);
      // reading a text file > datafile.text placed in c:\jdk1.3.1\bin
      int [] measuredval = new int[numofpoints +1];
      int measuredvalue;
      try {
//       RandomAccessFile f = new RandomAccessFile ("c:\\jdk1.3.1\\bin\\datafile.txt", "r");
* Comments by V.V.
* disk files are random but streams from network are not.  Since the data is being read sequentially anyway,
* the modifications shown below will allow you to read the data file without the need for the applet to be signed
         URL url=new URL(Codebase,"datafile.txt");                       //<---------- put file in same directory as the class file ---- V.V.
         InputStream in;                                                 //<---------- V.V.
         URLConnection connection=url.openConnection();                  //<---------- V.V.
         in=connection.getInputStream();                                 //<---------- V.V.
         BufferedReader f=new BufferedReader(new InputStreamReader(in)); //<---------- V.V.
         int dataarraysize = 0;
         String s;
         while ((s=f.readLine()) != null ) {
            StringTokenizer st = new StringTokenizer(s);
            while (st.hasMoreTokens()) {
               measuredvalue = Integer.parseInt(st.nextToken());
               if (dataarraysize < numofpoints +1) measuredval[dataarraysize] = measuredvalue;
               if (dataarraysize>numofpoints) {
                  measuredval[numofpoints] = measuredvalue;
                  for (int k =1; k <= (numofpoints -1); k++) measuredval[k] = measuredval[k+1];
               dataarraysize++;
         // end while
      // end try
      catch (Exception e) {
         System.out.println("Execption in constructor readertext13: "+e);
      // end catch
      for (int a = 0;a<=(numofpoints -1);a++){
         if (measuredval[a] < 0) measuredval[a] = 0;
         if (measuredval[a] > screenheight) measuredval[a] = screenheight;
         //System.out.println(""+measuredval[a]);
      // display date and temperature horizontally below the oscilloscope
      SimpleDateFormat now1 = new SimpleDateFormat("dd-MM-yyyy hh:mm:ss");
      Date now = new Date();
      String nowstring = now1.format(now);
      g.setColor(measuredvaldispbgnd);
      g.fillRect(screenright - 4,ymax+5+40,screenwidth+8,20);
      int val = measuredval[numofpoints-1];
      g.setColor(fontColor);
      g.drawString(""+nowstring +
         " Temperature = "+val+
         "�C", screenright+10,ymax +
         20+40);
      // x axis labelling - temporary
      SimpleDateFormat axisdate = new SimpleDateFormat("mm:ss");
      Date noww = new Date();
      while (initialiser) {
         for (int ii = 0; ii<13;ii++) nowdate[ii] = axisdate.format(noww);
         initialiser = false;
      //---------------888888888888888
      // labelling x axis - time for each column
      for (int nw = 0;nw<12;nw++){
         nowdate[nw] = nowdate[nw +
            1];
      nowdate[12] = axisdate.format(now);
      int wn = 0;
      while (wn <12) {
         g.drawString(nowdate[wn], screenright wn*40 - 17 ,screentopscreenheight+20);
         g.drawString(nowdate[wn+1], screenright +(wn+1)*40-17 ,screentop+screenheight+20);
         wn = wn +2;
      g.drawString(nowdate[12], screenright +
         numofcolumns*40-17 ,screentop+screenheight+20);
      // label y axis
      //labeling vertical axis
      g.setColor(fontColor);
      for (int n = 0;n<11;n++) {
         int gridlabel = (screenheight - n*40);
         g.drawString(""+gridlabel+
            "�C", screenright - 45,screentop+screenheight*n/10 +4);
      // title label
      g.setColor(measuredvaldispbgnd);
      g.fillRect(screenright-3,5,screenwidth+5,20);
      g.setColor(fontColor);
      g.drawString("Graph of temperature measured against time at which it was measured", screenright+7, 18);
      // end label axes
      // draw another graphic , vertical display
      g.setColor(Color.gray);
      g.fillRect(xmax+10,screentop,16,screenheight+4 );
      g.setColor(gridColor);
      g.fillRect(xmax+12,screentop+2,12,screenheight);
      // above are fixed rectangles below is a pulsating rectangle depending on val
      g.setColor(oscilloBgnd);
      int zerotemp = screentop +
         screenheight +
         2;
      int temperature = screenheight - val;
      g.fillRect(xmax+12,screentop+2,12,temperature);
      // end draw another graphic--------------------------------------------------------------
      // graphic display of temperature -- this is most important, the movie
      originx = screenright;
      originy = screentop +
         screenheight - measuredval[0];
      // draw 10 line segments
      for (int i = 1; i <= (numofpoints -1);i++){
         g.setColor(lineColor);
         g.drawLine(originx,originy,originx+grid,screentop +
            screenheight - measuredval[ i ]);
         // the starting point is originx, originy
         // the lowest point of the oscillograph is taken as 0, so screentop + screenheight
         // the end point of the line is originx+grid,screentop + screenheight - measuredval
         // the above coordinates become the next starting point
         originx = originx+grid;
         originy = screentop +
            screenheight - measuredval[ i ];
      // ending paint
   public void destroy() {
   public void start() {
      timer = new Thread(this);
      timer.start();
   public void stop() {
      timer = null;
   public void run() {
      Thread me = Thread.currentThread();
      while (timer == me) {
         try {
            Thread.currentThread().sleep(delay);
            // wait for delay ms
         catch (InterruptedException e) {
            System.out.println("Exception in method run: "+e);
         repaint();
   // start update to avoid flickering of the image
   private Image offScreenImage;
   private Dimension offScreenSize;
   private Graphics offScreenGraphics;
   public final synchronized void update (Graphics g) {
      Dimension d = getSize();
      if ((offScreenImage == null) || (d.width != offScreenSize.width) || (d.height != offScreenSize.height)) {
         offScreenImage = createImage(d.width, d.height);
         offScreenSize = d;
         offScreenGraphics = offScreenImage.getGraphics();
      offScreenGraphics.clearRect(0, 0, d.width, d.height);
      paint(offScreenGraphics);
      g.drawImage(offScreenImage, 0, 0, null);
   // end update ton avoid flickering
// end applett