No suitable driver found for jdbc://localhost

Question

I have a simple servlet deployed on a Jetty 9 server on Ubuntu 14.04. It was working fine till yesterday. But after a system crash, i had problems with MySQL server, so had to make configuration changes to the mysql server to make it work ie added the line socket = /tmp/mysql.sock under sections [mysqld] and [client] in my.cnf

But now the servlet is not working. It gives me the below error.

java.sql.SQLException: No suitable driver found for jdbc:mysql://localhost/slappdb
    at java.sql.DriverManager.getConnection(Unknown Source)
    at java.sql.DriverManager.getConnection(Unknown Source)
    at slappserver.RegisterServlet.doGet(RegisterServlet.java:74)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:687)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
    at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:738)
    at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:551)
    at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143)
    at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:568)
    at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:221)
    at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1111)
    at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:478)
    at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:183)
    at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1045)
    at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)
    at org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:199)
    at org.eclipse.jetty.server.handler.HandlerCollection.handle(HandlerCollection.java:109)
    at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97)
    at org.eclipse.jetty.server.Server.handle(Server.java:462)
    at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:279)
    at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:232)
    at org.eclipse.jetty.io.AbstractConnection$2.run(AbstractConnection.java:534)
    at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:607)
    at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:536)
    at java.lang.Thread.run(Unknown Source)

I have made no changes to the servlet code at all :

final String DB_URL = DatabaseParameters.SlappDbURL;
final String USER = DatabaseParameters.DbServer_Username;
final String PASSWORD = DatabaseParameters.DbServer_Password;
conn = DriverManager.getConnection(DB_URL, USER, PASSWORD);

The driver is at the same place as before : /home/faizal/DEV/jre1.7.0_55/lib/ext/mysql-connector-java-5.0.8-bin.jar , which is included in the build path of the project.

What could have gone wrong?

Answer 1

Something seemed to have got corrupted in my project because of the crash. It is working now after i added the line Class.forName("com.mysql.jdbc.Driver"); in the servlet. But this line is actually not required since i am using a JDBC 4 driver.

Interestingly, now even if i remove this line, it works. So, i am still not sure what was the problem, but atleast it's working as before without any change in code.