Java Database Connectivity (JDBC)

A more thorough investigation indeed shows the problem is due to my environment. Let me explain...

I do use class oracle.jdbc.OracleDriver.

As soon as the class oracle.jdbc.OracleDriver is loaded, the NoClassDefFound exception is raised by the class initializer of oracle.jdbc.driver.OracleDriver (oracle.jdbc.OracleDriver inherits from oracle.jdbc.driver.OracleDriver). However, the OracleDriver static initializer code catches Throwable, so everything should be just fine.

In my case, the exception is not caught! How is this possible?

I discovered this is due to the JVM option -XX:-UseSplitVerifier I have to use to workaround an Hibernate problem (https://hibernate.atlassian.net/browse/HHH-7544): when this option is set, the NoClassDefFound exception is *not* caught within the class initializer!

Some people say using -XX:-UseSplitVerifier is perfectly safe with Java 7, but there is obviously one case where it is not! I could not reproduce the try/catch issue with a simple testcase, so I suspect the issue is due to the bytecode from ojdbc7.jar when it is run with the split verifier.

Testcase with ojdbc7.jar:

package foo.bar;

public class Test {

    public static void main(String[] args) {

        System.out.println("Try loading class oracle.jdbc.OracleDriver...");

        try {

            Class.forName("oracle.jdbc.OracleDriver");

            System.out.println("OK: class loaded!");

        } catch (Throwable e) {

            System.out.println("Error: exception caught!");

            e.printStackTrace();

        }

    }

}

With only this class and ojdbc7.jar in the current directory, run the following tests:

>java -cp ojdbc7.jar;. foo.bar.Test

Try loading class oracle.jdbc.OracleDriver...

OK: class loaded!

>java -XX:-UseSplitVerifier -cp ojdbc7.jar;. foo.bar.Test

Try loading class oracle.jdbc.OracleDriver...

Error: exception caught!

java.lang.NoClassDefFoundError: oracle/security/pki/OraclePKIProvider

        at java.lang.Class.forName0(Native Method)

        at java.lang.Class.forName(Unknown Source)

        at foo.bar.Test.main(Test.java:6)

Caused by: java.lang.ClassNotFoundException: oracle.security.pki.OraclePKIProvider

        at java.net.URLClassLoader$1.run(Unknown Source)

        at java.net.URLClassLoader$1.run(Unknown Source)

        at java.security.AccessController.doPrivileged(Native Method)

        at java.net.URLClassLoader.findClass(Unknown Source)

        at java.lang.ClassLoader.loadClass(Unknown Source)

        at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)

        at java.lang.ClassLoader.loadClass(Unknown Source)

        ... 3 more