Individual appointments for the next two weeks can be scheduled through this script.

import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;

public class Three extends HttpServlet {

  public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

    response.setContentType("text/html");
    PrintWriter out = response.getWriter();
    HttpSession session = request.getSession(); 
    String message = (String)session.getAttribute("message"),
           compScore = (String)session.getAttribute("compScore"),
           userScore = (String)session.getAttribute("userScore"),
           secret = (String)session.getAttribute("secret"),
           attempts = (String)session.getAttribute("attempts"), // state ends here
           answer = request.getParameter("answer"); // input
    String me = request.getContextPath() + request.getServletPath();
    if (message != null) {
      int a = Integer.parseInt(answer),
          s = Integer.parseInt(secret),
          n = Integer.parseInt(attempts);
      if (a == s) { // they won
        message = "Good.";
        userScore = Integer.parseInt(userScore) + 1 + "";
        attempts = "0";
        secret = Math.round(Math.random() * 100) + "";
      } else {
        n += 1;
        if (n == 10) { // they lost
          message = "Bad.";
          compScore = Integer.parseInt(compScore) + 1 + "";
          attempts = "0";
          secret = Math.round(Math.random() * 100) + "";
        } else {
          if (a < s) {
            message = "Try higher.";
          } else {
            message = "Try lower.";
          }
          attempts = n + "";
        }
      }
    } else {
      message = "The game has started.";
      session.setAttribute("message", message);
      secret = Math.round(Math.random() * 100) + "";
      session.setAttribute("secret", secret);
      attempts = "0";
      session.setAttribute("attempts", attempts);
      compScore = "0";
      session.setAttribute("compScore", compScore);
      userScore = "0";
      session.setAttribute("userScore", userScore);
    }

    session.setAttribute("message", message);
    session.setAttribute("secret", secret);
    session.setAttribute("attempts", attempts);
    session.setAttribute("compScore", compScore);
    session.setAttribute("userScore", userScore);

    out.println(

"<form action=\"" + me + "\">" +
"  " + message + "<p>" +
" secret: " + secret + "<p>" +
" attempts: " + attempts + "<p>" +
"  (" + compScore + " - " + userScore + ") <p>" +
"  Type your answer here: <input type=\"text\" name=\"answer\"> <p> " +
"  Push <input type=\"submit\" value=\"Proceed\"> when ready. " +
"</form>"

    );

  }
}

The part in blue is the last step in the development. 
 

Do you know what name this part has in our template? 

 

• an old lab eleven (for good, simple templates)
• an old set of lecture notes (lecture notes twenty, for more information)

• web chat (part one)
• code walk for the web chat (for more details)
• (code walk part two)

import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;

public class Four extends HttpServlet {

  public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

    response.setContentType("text/html");
    PrintWriter out = response.getWriter();
    String message = request.getParameter("message"),
           compScore = request.getParameter("compScore"),
           userScore = request.getParameter("userScore"),
           secret = request.getParameter("secret"),
           attempts = request.getParameter("attempts"), // state ends here
           answer = request.getParameter("answer"); // input
    String me = request.getContextPath() + request.getServletPath();
    if (message != null) {
      int a = Integer.parseInt(answer),
          s = Integer.parseInt(secret),
          n = Integer.parseInt(attempts);
      if (a == s) { // they won
        message = "Good.";
        userScore = Integer.parseInt(userScore) + 1 + "";
        attempts = "0";
        secret = Math.round(Math.random() * 100) + "";
      } else {
        n += 1;
        if (n == 10) { // they lost
          message = "Bad.";
          compScore = Integer.parseInt(compScore) + 1 + "";
          attempts = "0";
          secret = Math.round(Math.random() * 100) + "";
        } else {
          if (a < s) {
            message = "Try higher.";
          } else {
            message = "Try lower.";
          }
          attempts = n + "";
        }
      }
    } else {
      message = "The game has started.";
      secret = Math.round(Math.random() * 100) + "";
      attempts = "0";
      compScore = "0";
      userScore = "0";
    }

    out.println(

"<form action=\"" + me + "\">" +
"  " + message + "<p>" +
" secret: " + secret + "<p>" +
" attempts: " + attempts + "<p>" +
"  (" + compScore + " - " + userScore + ") <p>" +
"  Type your answer here: <input type=\"text\" name=\"answer\"> <p> " +
"  Push <input type=\"submit\" value=\"Proceed\"> when ready. " +
"  <input type=\"hidden\" name=\"message\" value=\"" + message + "\">" +
"  <input type=\"hidden\" name=\"compScore\" value=\"" + compScore + "\">" +
"  <input type=\"hidden\" name=\"userScore\" value=\"" + userScore + "\">" +
"  <input type=\"hidden\" name=\"attempts\" value=\"" + attempts + "\">" +
"  <input type=\"hidden\" name=\"secret\" value=\"" + secret + "\">" +
"</form>"

    );

  }
}

• make sure your Tomcat is installed
• create a new context and make it reloadable
• add a servlet to the classes folder
• add a description in the associated web.xml for the servlet
• compile and access the servlet, change and recompile the servlet until done

After lab this week we can get started with Homework Five (and Six follows right away).

#!/usr/bin/perl

use DBI;
use MD5;
use CGI;

$EXPIRE    = 60 * 60 * 24 * 30;     # allow 30 days before expiration
$DB        = "DBI:mysql:a348";      # data source name (database)
$username  = "a348";                # username
$password  = "a348AG";              # password
$DBAUTH    = "$username:$password";
$SECRET    = " ***( something secret, whatever )*** ";
$MAX_TRIES = 10;

$DB_TABLE  = "ckotil_firstta"; 

$ID_LENGTH = 8;                     # length of the session ID

$q = new CGI;

# Open the database -------------------------------------------------------- 

$DBH = DBI->connect($DB, $username, $password, {PrintError => 0}) || die "Couldn't open database: ", $DBI::errstr;

# get the current session ID, or make one ----------------------------------
my ($session_id, $note) = &get_session_id();

print $q->header,
      $q->start_html(-title => 'Database Sessions with URL Rewriting',
                     -bgcolor => 'white');

# retrieve the state -------------------------------------------------------
my $state = &get_state($session_id) unless $q->param('clear');

$message = $state->{message};  
$comp = $state->{comp};
$user = $state->{user};

$guess = $q->param('guess'); 

if ($message) {
  $user += $guess;
  if ($user >= 100) { 
    print "You WIN!";
    $user=0;
  } else {
    $comp = 1 + int(rand(10)); # this is the number
    $user=$user + $comp;
  };

  if ($user>=100) { 
    print "I WIN!";
    $user=0;
  } 
} else {
  $message = "Welcome"; 
  $user = 0;
  $comp = -1; 
}

$state->{message} = $message;
$state->{comp} = $comp;
$state->{user} = $user; 

# save the modified state --------------------------------------------------
&save_state($state, $session_id);

print qq{<form>
  I have chosen $comp . <br> 
  The total is currently $user , remember first to 100 wins. <p> 
  How much will you enter? (0-10) <input type="text" name="guess"/> <p> 
  Press <input name="submit" type="submit" value="Submit"/> when ready to submit. 
  
</form>};


print $q->end_html;
$DBH->disconnect;

# retrieve the session ID from the path info. if it's -----get_session_id---
# not already there, add it to the path info (more or less) with a redirect
sub get_session_id {

  my (@result);
  &expire_old_sessions();
  my ($id) = $q->path_info() =~ m:^/([a-h0-9]{$ID_LENGTH}):o;
  return @result if $id and @result = &check_id($id);
  
  # if we get here, there's not already an ID in the path info
  my $session_id = &generate_id();
  die "Couldn't make a new session id" unless $session_id;
  print $q->redirect($q->script_name() . "/$session_id");
  exit 0;
}

# find a new unique ID and insert it into the database -------generate_id---
sub generate_id {
  # create a new session id
  my $tries = 0;
  my $id = &hash($SECRET . rand());

  while ($tries++ < $MAX_TRIES) {
    last if $DBH->do("INSERT INTO $DB_TABLE (session_id) VALUES ('$id')");
    $id = &hash($id);
  }

  return undef if $tries >= $MAX_TRIES; # we failed
  return $id;
}

# check to see that an old ID is valid --------------------------check_id---
sub check_id {
  my $id = shift;
  return ($id, '')
    if $DBH->do("SELECT 1 FROM $DB_TABLE WHERE session_id = '$id'") > 0;
  return ($id, 'The record of your game may have expired. Restarting.')
    if $DBH->do("INSERT INTO $DB_TABLE (session_id) VALUES ('$id')");
  return ();
}

# generate a hash value ---------------------------------------------hash---
sub hash {
  my $value = shift;
  return substr(MD5->hexhash($value), 0, $ID_LENGTH);
}

sub expire_old_sessions { # --------------------------expire_old_sessions---
  $DBH->do(<<END);
DELETE FROM $DB_TABLE
  WHERE (unix_timestamp() - unix_timestamp(modified)) > $EXPIRE
END
}

# get the state from the database ------------------------------get_state---
sub get_state {
  my $id = shift;  
  my $query =
      "SELECT * FROM $DB_TABLE WHERE session_id = '$id'";
  my $sth = $DBH->prepare($query) || die "Prepare: ", $DBH->errstr;
  $sth->execute || die "Execute: ", $sth->errstr;
  my $state = $sth->fetchrow_hashref;
  $sth->finish;
  return $state;
}


# save the state in the database ------------------------------save_state---
sub save_state {
  my ($state, $id) = @_;
  my $sth = $DBH->prepare(<<END) || die "prepare: ", $DBH->errstr;
UPDATE $DB_TABLE
  SET message=?,comp=?,user=?
  WHERE session_id='$id'
END
  $sth->execute(@{$state}{qw(message comp user)})
    || die "execute: ", $DBH->errstr;
  $sth->finish;
} 

Please review the notes posted for Thu and Fri, labs will focus exclusively on Homework Four.

That is: keeping state with CGI using custom sessions and DBI for database access.

We start on server-side Java, JDBC and discuss the remaining hoemwork assignments.

Please check your grades in A348-0205, they have been updated Monday morning to include the exams.

The next few homework assignments are:

Homework Four	The exam problem implemented with CGI/DBI and server side state
Homework Five	The exam problem implemented with servlets (hidden fields and session based)
Homework Six	The exam problem implemented using Java Server Pages (hidden fields and sessions)
Homework Seven	The exam problem implemented using Javascript and DHTML

Due dates will be posted soon. Labs will be dedicated to helping with homework.

We also need to pay attention to the project, and your design documents are due this coming week, in lab.

More details on what is needed will be posted here and sent by e-mail to you Sun morning:

Date: Sun, 26 Mar 2006 09:28:51 -0500 (EST)
From: Adrian German <dgerman@cs.indiana.edu>
To: A348/A548 Spr. 2006 Distr. List <dgerman@indiana.edu>
Subject: project design documents due in lab this coming week (03/30-31)

As discussed in lab last week design documents for your projects are due
in lab this coming Thu and Fri 03/30-31. You need to describe the screens
and basic functionality of your project as if it's finished, and you want
to pitch it for sale or funding to someone else (me, Craig and Minh).

We will collect these documents and I will give you feedback by the Tue
that follows (04/04). I will tell you how much is enough for A348/A548 and
how I think you "implemented" it. It will be up to you to use the feedback
in any way you want, and the most convenient implementation method for you
but we would then have two more stages in which you would have to show us
the project on the computer, as it's being developed.

Tue we go back to Tomcat, Java servlets and Java Server Pages. The lecture
on PHP/ColdFusion is canceled and we will instead discuss server-side Java,
JDBC and Perl CGI/DBI. This will take care of the next 3 hw assignments (4,
5 and 6) after which we can approach the last assignment (7) which will be
implementing the midterm exam problem using Javascript and DHTML.

Grades up to Lab 10 and Homework 3 and the Midterm Exam are being posted.

If you have any questions or need any help please let me know.

... Adrian

Next an announcement will be made regarding this coming lab and the remaining homework assignments.

EDITOR=pico
export EDITOR

PATH=/usr/local/gnu/bin:$PATH:/home/user1/mysql/bin
export PATH

JAVA_HOME=/l/jdk1.5
export JAVA_HOME
CATALINA_HOME=/u/dgerman/tomcat/jakarta-tomcat-5.5.9
export CATALINA_HOME
CLASSPATH=.:$CATALINA_HOME/common/lib/servlet-api.jar
export CLASSPATH

• Here are the instructions.
• Here's a quick introduction to Java servlets and Java Server Pages.
• And here's the continuation.

• A servlet link. And a JSP link.

<?xml version="1.0" encoding="ISO-8859-1"?>

<!DOCTYPE web-app
    PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
    "http://java.sun.com/dtd/web-app_2_3.dtd">

<web-app>

    <servlet>
        <servlet-name>One</servlet-name>

        <servlet-class>One</servlet-class>

    </servlet>

    <servlet-mapping>
        <servlet-name>One</servlet-name>

        <url-pattern>/servlet/One</url-pattern>

    </servlet-mapping>

    <servlet>
        <servlet-name>Fv2_3</servlet-name>

        <servlet-class>Two</servlet-class>

    </servlet>

    <servlet-mapping>
        <servlet-name>Fv2_3</servlet-name>

        <url-pattern>/servlet/Fancy</url-pattern>

    </servlet-mapping>


</web-app>

<Server port="15477" shutdown="SHUTDOWN">

  <GlobalNamingResources>
    <!-- Used by Manager webapp -->
    <Resource name="UserDatabase" auth="Container"
              type="org.apache.catalina.UserDatabase"
       description="User database that can be updated and saved"
           factory="org.apache.catalina.users.MemoryUserDatabaseFactory"
          pathname="conf/tomcat-users.xml" />
  </GlobalNamingResources>

  <Service name="Catalina">
    <Connector port="15476" />

    <Engine name="Catalina" defaultHost="localhost">
      <Realm className="org.apache.catalina.realm.UserDatabaseRealm"
             resourceName="UserDatabase" />

      <Host name="localhost" appBase="webapps">

        <Context path="/nov09" docBase="nov09" debug="0" reloadable="true" />

      </Host>

    </Engine>

  </Service>
</Server>

<?
   function get_book_cats($isbn) {

       $conn = db_connect(); 

       $query = "select dgerman_php_catboo.catid, catname 
                 from dgerman_php_categories, dgerman_php_catboo 
                 where '$isbn' = dgerman_php_catboo.isbn and
                       dgerman_php_categories.catid = dgerman_php_catboo.catid"; 

       $result = @mysql_query($query); 


       if (! $result) return false;



       $num_cats = @mysql_num_rows($result); 
       if ($num_cats == 0) return false; 



              $cat_array = array(); 

              for (
                   $count = 0; 
                   $row = @mysql_fetch_array($result); 
                   $count++
                  ) 
                $cat_array[$count] = $row; 

       if (! is_array($cat_array)) {
                     echo "No categories currently available. <br>"; 
              }



              foreach ($cat_array as $row) {

                     $url = "show_cat.php?catid=".($row["catid"]); 
                     $title = $row["catname"]; 



                     do_html_url($url, $title); 

              }


   } 
 ?>

• Thu Mar 23 Krishna Kumar (Microsoft, Introducing ASP.NET)

• Tue Mar 28 Aaron Bond (UITS, Using PHP to emulate ColdFusion)

I will post more details as we get closer to those dates.

Krishna will also buy pizza and soft drinks for everybody for his lecture.

1. stage one
2. stage two
3. stage three
4. stage four
5. stage five
6. stage six
7. stage seven

As far as tables are concerned you can see how we got started here.

Here's the lab for this week:

• part one
• part two

Homework One (Apache, HTML)	Lab Assignment One (Unix, archiving)
Homework Two Flag Quiz (CGI/h)	Lab Assignment Two (Basic CGI/CGI.pm) helloFive (source code) circular lindley portfolio (next/previous)
Homework Three: Flag Quiz (PHP/h) Flag Quiz (PHP/s)	Lab Assignment Three: password protection PHP installation
Lab Assignment Four basic HTTP GET vs. POST	Lab Assignment Five: First to 100 (CGI/h) First to 100 (PHP/h) First to 100 (PHP/s)
Lab Assignment Six: Guess the Number (CGI/h) Guess the Number (PHP/h) Guess the Number (PHP/s)	Lab Assignment Seven: Addition Quiz (CGI/h) Addition Quiz (PHP/h) Addition Quiz (PHP/s)

1. program one (source code)
2. program two (source code)

program one (source code) program two (source code) program three (source code) program four (source code)

dgerman:xAzOFxiQYqKxE

• first I chose to implement using sessions
• next I make minor changes to obtain hidden fields version
• finally, I convert the hidden fields PHP version to the hidden fields CGI version

You must be able to start seeing how close these programs are to each other!

They're almost, almost identical.

1. a version written in CGI/Perl using hidden fields to keep state
2. a version written in PHP using session variables to keep state, and
3. a version written in PHP using hidden fields to keep state.

In class we will discuss server-side management of state (in general).

We will then develop tools to implement that using CGI/Perl and MySQL.

Jun Yin Jun Yin's Spiffy Lab Five Program

Keira Johnson Keira Johnson's Homework Two

Jonathan Warren Jonathan Warren's Homework Two

This list is not exhaustive by any means.

But I hope it is a source of inspiration to all of us.

A note from a former student.

Their prototype is the minute paper for Tue: this program developed with CGI.pm.

#!/usr/bin/perl

%images = (
  "One"     =>    "http://www.cs.indiana.edu/dept/img/lh01.gif", 
  "Seven"   =>    "http://www.cs.indiana.edu/dept/img/lh07.gif", 
  "Eight"   =>    "http://www.cs.indiana.edu/dept/img/lh08.gif", 
  "Nine"    =>    "http://www.cs.indiana.edu/dept/img/lh09.gif"
); 

@keys = ("One", "Seven", "Eight", "Nine"); 

use CGI; 
$q = new CGI; 

print $q->header, $q->start_html;

$index = $q->param('index'); # read the value for the parameter named index in the input 

$action = $q->param('action'); 

if ($action eq "previous") { 
  $index = $index -1 ; 
  if ($index < 0) { $index = 3; } 
} elsif ($action eq "next pic") { 
  $index = $index + 1; 
  if ($index >= 4) { $index = 0; } 
} else { 
  $index = 0; 
} 

$key = $keys[$index]; 
$picture = $images{$key}; 

print qq{
  <form>
  <table>
  <tr> <td> <input type="submit" name="action" value="previous">
       <td align=right> <input type="submit" name="action" value="next pic">
  <tr> <td colspan=2> You are looking at picture $key 
  <tr> <td colspan=2> <img src="$picture">

  </table>
  <input type="hidden" name="index" value="$index">
  </form>
}; 

print $q->end_html; 

register_globals = On

Here's the PHP code we developed at the end of Thu's class:

<?
   $balance += $amount;

?>

<form>
The current balance is: <? echo $balance; ?> <p>

Please enter the amount here: <input type="text" name="amount"> <p>

Chooose an action: <select name="what">
  <option value="none"> Click me!
  <option value="deposit"> Deposit
  <option value="withdraw"> Withdraw
</select>

<input type="hidden" name="balance" value="<? echo $balance; ?>">

<p> Please press <input type="submit" value="Proceed"> when ready.

</form>



#!/usr/bin/perl

@answers = ("zero", "one", "two", "three", "four", "five", "six", "seven"); 

use CGI;

$q = new CGI; 

print $q->header, $q->start_html; 

$times = $q->param('times'); 
$times += 0; 
$action = $q->param('action'); 
$userInput = $q->param('userInput'); 

if ($answers[$times] eq $userInput) { # skip it first time around 
  $message = "Very good, that was the answer."; 
} else { 
  $message = "Too bad, better be more careful next time."; 
} 

if ($action =~ /next/) { $times += 1; } 
elsif ($action =~ /previous/) { $times -= 1; } 
else { } 
#--------------------(no printing above on  purpose)-------
print qq{
  <form>
    <table>
    <tr> <td> <input type="submit" name="action" value="previous"> 
         <td> <input type="submit" name="action" value="next"> 
    <tr> <td colspan=2> $message         
    <tr> <td colspan=2> You are looking at picture: $times <p> 
    <input type="hidden" name="times" value="$times"> 
    <tr> <td colspan=2> Please type here the number you see: 
                        <input type="text" name="userInput"> 
    </table>
  </form> 
};

print $q->end_html; 

In class we will discuss keeping state on the server side (tutorial 12 and the associated example).

• the code we wrote in class on Thu
• the diagram for the basic framework

• the pictures for the quiz program (Homework Two) are here

Don't forget that Homework Two is just like the Lab Assignment Two program.

Except we also collect the answers, which we grade, and tally.

#!/usr/bin/perl

print qq{Content-type: text/html\n\n<html><head><title>CGI Processor</title><head><body bgcolor="white">};

&readParse; 

foreach $k (keys %in) {
  print $k, " --> ", $in{$k}, "<br>"; 
}

$input = $ENV{"QUERY_STRING"}; 

print qq{
  ($input) <hr> 

  <form>
    <table border cellpadding=3>
      <tr> <td> Field one: <td> <input type="text" name="one"> 
      <tr> <td> Field two: <td> <input type="text" name="two"> 
    </table> <p> 
    Please press <input type="submit" value="Proceed"> 
  </form>
};

print qq{</body></html>}; 

sub readParse {
  $user = $ENV{"QUERY_STRING"}; 
  @pairs = split(/&/, $user); 
  foreach $pair (@pairs) {
    ($name, $value) = split(/=/, $pair, 2); 
    $value =~ s/%(..)/chr(hex($1))/ge; 
    $in{$name} = $value; 
  } 
}

#!/usr/bin/perl

print qq{Content-type: text/html\n\n<html><head><title>CGI Processor</title><head><body bgcolor="white">};

&readParse; 

%images = (
  "One"     =>    "http://www.cs.indiana.edu/dept/img/lh01.gif", 
  "Seven"   =>    "http://www.cs.indiana.edu/dept/img/lh07.gif", 
  "Eight"   =>    "http://www.cs.indiana.edu/dept/img/lh08.gif", 
  "Nine"    =>    "http://www.cs.indiana.edu/dept/img/lh09.gif"
); 

$pic = "lh01.gif"; 

$pic = $in{"pic"} if ($images{$in{"pic"}}); 

if ($in{"Next"}) {
   
} elsif ($in{"Previous"}) {
  
} else {

}

print qq{
  <form>
    <table>
    <tr>
    <td> <input type="submit" name="previous" value="Previous">
    <td> <input type="submit" name="next" value="Next">
    <tr><td colspan=2> <img src="http://www.cs.indiana.edu/dept/img/$pic">
    </table> 
    <input type="hidden" name="pic" value="$pic"> 
  </form> 

};

print qq{</body></html>}; 

sub readParse {
  $user = $ENV{"QUERY_STRING"}; 
  @pairs = split(/&/, $user); 
  foreach $pair (@pairs) {
    ($name, $value) = split(/=/, $pair, 2); 
    $value =~ s/%(..)/chr(hex($1))/ge; 
    $in{$name} = $value; 
  } 
}

Here's a framework we need to start understanding.

(They're mostly in the right places, they just need to be cleaned up a bit).

Click here to see if your archive is accessible.

	Thursday lab 3:35pm-5:30pm Lindley Hall 115 Craig Shue (assisted by Minh Tang)
	Friday first lab 10:10am-12:05pm Lindley Hall 025 Adrian German (assisted by Craig Shue)
	Friday second lab 12:20pm- 2:15pm Lindley Hall 025 Minh Tang (assisted by Adrian German)

chmod 711 ~
chmod 755 ~/public
chmod 644 ~/public/whoa.tar.gz

1. create a ~/.bash-profile file with two lines
2. first line reads EDITOR=pico
3. second line reads export EDITOR

From here on every time you login pico is your default editor.

Type crontab -e to use it to change your crontab entries.

Lab notes for this week will be finalized Tuesday night.

Attendance (minute papers) is collected here: A348-0205.
(PostEm will soon appear listed as a tool in OnCourse.)

CSCI-A 348/A548 (14754/14764)  R  3:35PM - 5:30PM

Please make a note of it (location is close to the original venue).

LEC	1:00pm-	2:15pm	TR	LH102	German
LAB	3:35pm-	5:30pm	R	ED2025
LAB	10:10am-	12:05pm	F	LH025
LAB	12:20pm-	2:15pm	F	LH025