progNewbie progNewbie - 5 months ago 22
MySQL Question

com.mysql.jdbc.Driver not found after deploying project to Tomcat

I had a webproject in Eclipse, which uses a connection to my mysql database.

I exported the project as .WAR-File and deployed it on a different machine to the tomcat server. On that machine there is also the mysql-database.

I do this:

envContext = new InitialContext();
DataSource ds = (DataSource) envContext.lookup( "java:comp/env/jdbc/Database" );
con = ds.getConnection();


My Context.xml:

<Resource name="jdbc/Database" auth="Container"
type="javax.sql.DataSource"
maxActive="100" maxIdle="30" maxWait="10000"
username="user"
password="pw"
driverClassName="com.mysql.jdbc.Driver"
url="jdbc:mysql://localhost:3306/databasename"/>


But I get this error:

java.sql.SQLException: com.mysql.jdbc.Driver
at org.apache.tomcat.jdbc.pool.PooledConnection.connectUsingDriver(PooledConnection.java:254)
at org.apache.tomcat.jdbc.pool.PooledConnection.connect(PooledConnection.java:182)
at org.apache.tomcat.jdbc.pool.ConnectionPool.createConnection(ConnectionPool.java:701)
at org.apache.tomcat.jdbc.pool.ConnectionPool.borrowConnection(ConnectionPool.java:635)
at org.apache.tomcat.jdbc.pool.ConnectionPool.init(ConnectionPool.java:486)
at org.apache.tomcat.jdbc.pool.ConnectionPool.<init>(ConnectionPool.java:144)
at org.apache.tomcat.jdbc.pool.DataSourceProxy.pCreatePool(DataSourceProxy.java:116)
at org.apache.tomcat.jdbc.pool.DataSourceProxy.createPool(DataSourceProxy.java:103)
at org.apache.tomcat.jdbc.pool.DataSourceFactory.createDataSource(DataSourceFactory.java:554)
at org.apache.tomcat.jdbc.pool.DataSourceFactory.getObjectInstance(DataSourceFactory.java:242)
at org.apache.naming.factory.ResourceFactory.getObjectInstance(ResourceFactory.java:141)
at javax.naming.spi.NamingManager.getObjectInstance(NamingManager.java:321)
at org.apache.naming.NamingContext.lookup(NamingContext.java:842)
at org.apache.naming.NamingContext.lookup(NamingContext.java:153)
at org.apache.naming.NamingContext.lookup(NamingContext.java:830)
at org.apache.naming.NamingContext.lookup(NamingContext.java:153)
at org.apache.naming.NamingContext.lookup(NamingContext.java:830)
at org.apache.naming.NamingContext.lookup(NamingContext.java:153)
at org.apache.naming.NamingContext.lookup(NamingContext.java:830)
at org.apache.naming.NamingContext.lookup(NamingContext.java:167)
at org.apache.naming.SelectorContext.lookup(SelectorContext.java:156)
at javax.naming.InitialContext.lookup(InitialContext.java:411)
at bachelor.Cronjob.run(Cronjob.java:63)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:304)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThr$
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPool$
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:278)
at org.apache.tomcat.jdbc.pool.PooledConnection.connectUsingDriver(PooledConnection.java:246)
... 29 more


In the "WEB-INF/lib"-Folder I got the 'mysql-connector-java-5.1.35-bin.jar'.

Does anyone know why it works in eclipse but not in tomcat on the other machine? Thanks alot!

Answer

I am almost sure that if you use a JNDI datasource defined in Context.xml, the DB driver has to be in $CATALINA_HOME/lib, i.e. it is not enough to have it in WEB-INF/lib.

(Some Tomcat installations have different CATALINA_HOME and CATALINA_BASE, so if you cannot find the proper lib folder, then probably the easiest way to find where it is is to run ps axwww | grep -i catalina command and then to look for the -Dcatalina.home=... option.)

Comments