I'm having some trouble getting classes loaded by a new classloader to be able to see classes which should have been loaded automatically from WEB-INF/lib. All of the documentation that I've seen so far (FAQs, mailing list searches, ...) describe problems that people have had using the standard classloader that Tomcat provides, but I have yet to see one dealing with dynamically loading classes from a new classloader defined within a webapp.
More specifically, here is my problem: I am developing an application suite involving a database backend which feeds and is updated by server processes and a Web UI. To support multiple databases, database modules (JAR files) can simply be dropped in and loaded by each application dynamically. The problem is that when the Web UI loads the database module, that module is unable to actually load the JDBC driver (org.postgresql.Driver) which is packaged in WEB-INF/lib/postgresql-8.3-604.jdbc4.jar (I've checked the case of the path components). This is definitely related to classloaders; I tried placing the database module directly into my WAR file under WEB-INF/classes/package/name/PostgreSQLDatabale.class and it worked. But if I do that, I lose the modularity and easy-upgrading that I achieved by going with the dynamic loading of classes from JARs. I'm using java.net.URLClassLoader with the parent classloader set to the classloader that loaded my application classes, so it should theoretically be the same classloader used to load the postgresql-8.3-604.jdbc4.jar file. Has anyone else encountered a problem like this? Any suggestions on what else I should try? Thanks in advance! Jonathan P. Pearson - Software Engineer -------------------------------------------------- SIXNET - Solutions for Your Industrial Networking Challenges 331 Ushers Road, Ballston Lake, NY 12019 Tel: 1.518.877.5173, Fax: 1.518.877.8346 www.sixnet.com --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
