Re: connecting jsp with mysql

2011-02-22 Thread Christopher Schultz 
-BEGIN PGP SIGNED MESSAGE-
Hash: SHA1

Anup,

On 2/21/2011 10:20 AM, Anup Niroula wrote:
 Hi,
 out.println (Cannot connect to database server message +e.getMessage());
 This gives following error msg:
 Cannot connect to database server com.mysql.jdbc.Driver.

How about e.printStackTrace()? Post the entire message and full stack trace.

I can see a whole bunch of things wrong with your original code:

1. You re-register the driver for every request (Class.forName) which
   isn't that big of a deal... just a waste of time at least for the
   MySQL driver. It's mostly just bad coding practice.

2. You create a new Connection for every request. You would be much
   better off using pooled connections. Look at the Tomcat documentation
   for using JNDI DataSources.

3. You swallow nearly all exceptions. At least log them.
   System.err/System.out doesn't count.

4. You shouldn't have any Java code in a JSP (debatable).

5. Everything is hard-coded. Of course, this looks like a test page
   so you can be excused for that :)

- -chris
-BEGIN PGP SIGNATURE-
Version: GnuPG v1.4.10 (MingW32)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/

iEYEARECAAYFAk1kFrEACgkQ9CaO5/Lv0PC62QCeIpgG7Wu3fZNcNKfsm+5Mxn4w
3RwAniITH/47q9NrkdiqZK2CgPJWUhFA
=+hIO
-END PGP SIGNATURE-

-
To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org
For additional commands, e-mail: users-h...@tomcat.apache.org

Re: connecting jsp with mysql

2011-02-21 Thread Mikolaj Rydzewski 


On Mon, 21 Feb 2011 07:55:05 -0600, Anup Niroula 
anup.niro...@gmail.com wrote:

   catch (Exception e)
   {
   out.println (Cannot connect to database server);
   }


I guess the answer is hidden within 'e'.

Anyway, you should rather use JNDI 
http://tomcat.apache.org/tomcat-7.0-doc/jndi-resources-howto.html

Or at least any framework (spring, dbutils, etc).

--
Mikolaj Rydzewski m...@ceti.pl

-
To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org
For additional commands, e-mail: users-h...@tomcat.apache.org

RE: connecting jsp with mysql

2011-02-21 Thread Caldarale, Charles R 
 From: Anup Niroula [mailto:anup.niro...@gmail.com] 
 Subject: connecting jsp with mysql

 I downloaded jdbc driver mysql-connector-java-5.1.15-bin.jar 
 and placed it in two locations:
- CATALINE_HOME\lib
- C:\Program Files\Apache Software Foundation\Tomcat
7.0\webapps\lsc\WEB-INF\lib

Fatal error.  Place the jar file in *one* location only.  If you're using 
Tomcat's DBCP capability, it must go into CATALINA_HOME/lib; if your webapp is 
doing all the DB connection handling, it must be in the webapp's WEB-INF/lib 
directory.

 - Chuck


THIS COMMUNICATION MAY CONTAIN CONFIDENTIAL AND/OR OTHERWISE PROPRIETARY 
MATERIAL and is thus for use only by the intended recipient. If you received 
this in error, please contact the sender and delete the e-mail and its 
attachments from all computers.


-
To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org
For additional commands, e-mail: users-h...@tomcat.apache.org

RE: connecting jsp with mysql

2011-02-21 Thread Martin Gainty 

1)putting a lightly loaded engine light on text message is neither helpful 
nor delivers any useful information to those of us trying to determine your 
error 
always include the message from the exception object e.g.
out.println (Cannot connect to database server message=+e.getMessage());

2)
netstat -a | grep 3306
if you dont see tcp connection displayed on your output then mysql daemon is 
down..restart it

3)never put username and password on emails ..this is not a secure way to do 
business 
btw try implementing the same username to get into mysql 
$MYSQL_HOME/bin/mysql.exe --host=localhost --user=whatever_user 
--password=whatever_password --host=localhost

Martin Gainty 
__ 
Jogi és Bizalmassági kinyilatkoztatás/Verzicht und 
Vertraulichkeitanmerkung/Note de déni et de confidentialité
 Ez az
üzenet bizalmas.  Ha nem ön az akinek szánva volt, akkor kérjük, hogy
jelentse azt nekünk vissza. Semmiféle továbbítása vagy másolatának
készítése nem megengedett.  Ez az üzenet csak ismeret cserét szolgál és
semmiféle jogi alkalmazhatósága sincs.  Mivel az electronikus üzenetek
könnyen megváltoztathatóak, ezért minket semmi felelöség nem terhelhet
ezen üzenet tartalma miatt.

Diese Nachricht ist vertraulich. Sollten Sie nicht der vorgesehene Empfaenger 
sein, so bitten wir hoeflich um eine Mitteilung. Jede unbefugte Weiterleitung 
oder Fertigung einer Kopie ist unzulaessig. Diese Nachricht dient lediglich dem 
Austausch von Informationen und entfaltet keine rechtliche Bindungswirkung. 
Aufgrund der leichten Manipulierbarkeit von E-Mails koennen wir keine Haftung 
fuer den Inhalt uebernehmen.
Ce message est confidentiel et peut être privilégié. Si vous n'êtes pas le 
destinataire prévu, nous te demandons avec bonté que pour satisfaire informez 
l'expéditeur. N'importe quelle diffusion non autorisée ou la copie de ceci est 
interdite. Ce message sert à l'information seulement et n'aura pas n'importe 
quel effet légalement obligatoire. Étant donné que les email peuvent facilement 
être sujets à la manipulation, nous ne pouvons accepter aucune responsabilité 
pour le contenu fourni.




 Date: Mon, 21 Feb 2011 07:55:05 -0600
 Subject: connecting jsp with mysql
 From: anup.niro...@gmail.com
 To: users@tomcat.apache.org
 
 Hi,
 
 I am having difficulty in connecting jsp and mysql using Tomcat 7.0 .
 I downloaded jdbc driver mysql-connector-java-5.1.15-bin.jar and placed it
 in two locations:
 
- CATALINE_HOME\lib
- C:\Program Files\Apache Software Foundation\Tomcat
7.0\webapps\lsc\WEB-INF\lib
 
 I tried to connect using the following code but it always says:Cannot
 connect to database server.
  Do i need to make any configurations apart from this ?
 I tried to connect with the following code:
   %@page language=java import=java.sql.*%
 %
   Connection conn = null;
 
   try
{
String userName = root;
String password = nbuser;
String url = jdbc:mysql://localhost:3306/test;
Class.forName (com.mysql.jdbc.Driver).newInstance ();
conn = DriverManager.getConnection (url, userName, password);
out.println (Database connection established);
}
catch (Exception e)
{
out.println (Cannot connect to database server);
}
finally
{
if (conn != null)
{
try
{
conn.close ();
out.println (Database connection terminated);
}
catch (Exception e) { /* ignore close errors */ }
}
}
 %

Re: connecting jsp with mysql

2011-02-21 Thread Anup Niroula 
Hi,
out.println (Cannot connect to database server message +e.getMessage());
This gives following error msg:
Cannot connect to database server com.mysql.jdbc.Driver.
I am using windows 7.

On Mon, Feb 21, 2011 at 8:44 AM, Martin Gainty mgai...@hotmail.com wrote:


 1)putting a lightly loaded engine light on text message is neither
 helpful nor delivers any useful information to those of us trying to
 determine your error
 always include the message from the exception object e.g.
 out.println (Cannot connect to database server message=+e.getMessage());

 2)
 netstat -a | grep 3306
 if you dont see tcp connection displayed on your output then mysql daemon
 is down..restart it

 3)never put username and password on emails ..this is not a secure way to
 do business
 btw try implementing the same username to get into mysql
 $MYSQL_HOME/bin/mysql.exe --host=localhost --user=whatever_user
 --password=whatever_password --host=localhost

 Martin Gainty
 __
 Jogi és Bizalmassági kinyilatkoztatás/Verzicht und
 Vertraulichkeitanmerkung/Note de déni et de confidentialité
  Ez az
 üzenet bizalmas.  Ha nem ön az akinek szánva volt, akkor kérjük, hogy
 jelentse azt nekünk vissza. Semmiféle továbbítása vagy másolatának
 készítése nem megengedett.  Ez az üzenet csak ismeret cserét szolgál és
 semmiféle jogi alkalmazhatósága sincs.  Mivel az electronikus üzenetek
 könnyen megváltoztathatóak, ezért minket semmi felelöség nem terhelhet
 ezen üzenet tartalma miatt.

 Diese Nachricht ist vertraulich. Sollten Sie nicht der vorgesehene
 Empfaenger sein, so bitten wir hoeflich um eine Mitteilung. Jede unbefugte
 Weiterleitung oder Fertigung einer Kopie ist unzulaessig. Diese Nachricht
 dient lediglich dem Austausch von Informationen und entfaltet keine
 rechtliche Bindungswirkung. Aufgrund der leichten Manipulierbarkeit von
 E-Mails koennen wir keine Haftung fuer den Inhalt uebernehmen.
 Ce message est confidentiel et peut être privilégié. Si vous n'êtes pas le
 destinataire prévu, nous te demandons avec bonté que pour satisfaire
 informez l'expéditeur. N'importe quelle diffusion non autorisée ou la copie
 de ceci est interdite. Ce message sert à l'information seulement et n'aura
 pas n'importe quel effet légalement obligatoire. Étant donné que les email
 peuvent facilement être sujets à la manipulation, nous ne pouvons accepter
 aucune responsabilité pour le contenu fourni.




  Date: Mon, 21 Feb 2011 07:55:05 -0600
  Subject: connecting jsp with mysql
  From: anup.niro...@gmail.com
  To: users@tomcat.apache.org
 
  Hi,
 
  I am having difficulty in connecting jsp and mysql using Tomcat 7.0 .
  I downloaded jdbc driver mysql-connector-java-5.1.15-bin.jar and placed
 it
  in two locations:
 
 - CATALINE_HOME\lib
 - C:\Program Files\Apache Software Foundation\Tomcat
 7.0\webapps\lsc\WEB-INF\lib
 
  I tried to connect using the following code but it always says:Cannot
  connect to database server.
   Do i need to make any configurations apart from this ?
  I tried to connect with the following code:
%@page language=java import=java.sql.*%
  %
Connection conn = null;
 
try
 {
 String userName = root;
 String password = nbuser;
 String url = jdbc:mysql://localhost:3306/test;
 Class.forName (com.mysql.jdbc.Driver).newInstance ();
 conn = DriverManager.getConnection (url, userName,
 password);
 out.println (Database connection established);
 }
 catch (Exception e)
 {
 out.println (Cannot connect to database server);
 }
 finally
 {
 if (conn != null)
 {
 try
 {
 conn.close ();
 out.println (Database connection terminated);
 }
 catch (Exception e) { /* ignore close errors */ }
 }
 }
  %