Should JDBC drivers be included in a WAR?

Question

We have a commercial software product under development. It supports Oracle, MySQL, and SQL*Server backends (we also use H2 for testing). We do our integration testing against those different database using JDBC drivers of a specific version. Maven handles all this beautifully.

When packaging the application as a WAR, is it ok if we include the JDBC drivers? What is the standard practice?

Since we don't know which database could be used ahead of time, we'd have to include them all. The targeted servlet containers are Tomcat and Jetty, but some customers will also want to run within WebSphere and JBoss.

So the servlet contains and application servers come with their own JDBC drivers? Will ours conflict? Another concern is that we have developed and tested with one version of the driver and if a customer uses another version, we may have problems.

Currently we use Spring data source beans, but are in the process of moving to JNDI lookup for the datasource.

Answer 1

So the servlet contains and application servers come with their own JDBC drivers?

Some do (eg WebLogic).

Will ours conflict?

They shouldn't. Not sure yours will be picked when creating an standalone connection pool at the application level though (it all depends on the classloader delegation mode).

Another concern is that we have developed and tested with one version of the driver and if a customer uses another version, we may have problems.

Have a list of supported versions.

Currently we use Spring data source beans, but are in the process of moving to JNDI lookup for the datasource.

If by this you mean using the connection pool provided by an application server, drivers must be installed at the container level , not at the application level. And this somehow ends the discussion.

Answer 2

In most of the applications, JDBC drivers aren't shipped as part of the application.

If you do ship JDBC drivers, that means that you have to give drivers for all the database you want to support. It add a lot of unnecessary libraries.

Just don't add any driver, and tell the user to put the relevant JAR file in the server libraries if needed.

Answer 3

除了在war文件中包含驱动程序的技术优点之外，您还应检查驱动程序的许可，并确保它可由第三方分发。