Connecting mysql and tomcat

[srijith_bhandary]

Hi I am new to tomcat and mysql.

I have installed Tomcat and mysql and both are working great!!

But now I have task of connecting mysql and tomcat.
I dont have any idea on this. However I looked some manuals but did not find any luck.

Guy, Please give me the step by step procedure on how to connect mysql with tomcat.

btw I have downloaded mysql connector and copied the .jar file to $CATALINA_HOME/lib

What else should I do ?
Thanks!

[srijith_bhandary]

This is the steps I followed to install tomcat http://www.linuxnix.com/2010/12/how-to-install-apache-tomcat-on-linuxredhatubuntu.html and I installed mysql server and client using the commands sudo apt-get install mysql-server mysql-client later I downloaded JDBC Driver for MySQL (Connector/J) from http://www.mysql.com/products/connector/ and extrated it and pasted the .jar fille in /opt/apache-tomcat-6.0.29/lib ( I dont have $CATALINA_HOME/common/lib) . My questions are 1) Is the connection between tomcat and sql established ? 2) do i need to install mysql-server when I have tomcat server ?

[lykeion]

You can install JDBC driver for MySQL from Ubuntu repositories:

sudo apt-get install libmysql-java
Then add the jar-file /usr/share/java/mysql.jar to classpath in ~/.bashrc, see: https://help.ubuntu.com/community/JDBCAndMySQL
And possibly add this to your Tomcat startup script $CATALINA_HOME/bin/startup.sh as well.

[srijith_bhandary]

Hi thanks for the help.
I did what you said and everything finished great!

I then executed the java script to test ( in the link that you have mentioned) with username as root and with password

when I enter
$javac DBDemo.java

It gave me this error

DBDemo.java:4: error while writing DBDemo: DBDemo.class (Permission denied)
public class DBDemo
^
1 error

So I did
$sudo javac DBDemo.java and it worked

but I get the following error when I do $java DBDemo
com.mysql.jdbc.Driver
Exception in thread "main" java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
at java.net.URLClassLoader$1.run(URLClassLoader.java: 217)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.j ava:205)
at java.lang.ClassLoader.loadClass(ClassLoader.java:3 21)
at sun.misc.Launcher$AppClassLoader.loadClass(Launche r.java:294)
at java.lang.ClassLoader.loadClass(ClassLoader.java:2 66)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:186)
at DBDemo.main(DBDemo.java:22)

[lykeion]

The ClassNotFoundException means it the JDBC driver is not in the classpath.

1. Login to mysql as root user (if it's first time just press enter when prompted for password)

mysql -u root -p
2. Create the database

create database emotherearth;
3. Change database

use emotherearth;
4. Create a user and grant privileges to database

grant all privileges on emotherearth to paulr@localhost identified by "paulr";
5. Logout

quit;

6. Add JDBC driver to classpath

CLASSPATH=$CLASSPATH:/usr/share/java/mysql.jar
export CLASSPATH

7. Create the java file DBDemo.java (paste the contents from the JDBCAndMySQL (https://help.ubuntu.com/community/JDBCAndMySQL) page)

8. Compile it

javac DBDemo.java

9. Run it (if everything is okay it should display "It works !")

java DBDemo


You shouldn't need sudo privileges to access javac. It may be something strange you've done when installing JDK.
Could you please post the output of this command:

sudo update-java-alternatives -l