An interesting discovery today. I upg...

An interesting discovery today. I upgraded my development environment to Eclipse Galileo/Cocoa-64 yesterday. This caused a class-path issue that was unexpected. As it turns out Galileo packages Junit 4.5, and Junit 4.5 uses a signed version of hamcrest. This conflicts with JMock 2.2.0's hamcrest libraries and causes my tests where mocks are used to break with a java security exception. It looks sort of like this;

java.lang.SecurityException: class "org.hamcrest.TypeSafeMatcher"'s signer information does not match signer information of other classes in the same package
at java.lang.ClassLoader.checkCerts(ClassLoader.java:851)
at java.lang.ClassLoader.preDefineClass(ClassLoader.java:566)
at java.lang.ClassLoader.defineClass(ClassLoader.java:692)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)

So, the first thing I did was update JMock to the newest version thinking this was simply an issue with JDK versions or something. That didn't work, but it's helpful to have the 'latest and greatest' I guess, so no harm done. 

After some quick googling about I discovered the issue was multiple hamcrest libraries and simply changed my class-path order to place Junit at the end of the classpath (after JMock) and voila, problem solved.

So, if your moving to Galileo and your tests with mocks suddenly start breaking, the simple fix is to make sure JUnit follows JMock (and it's version of hamcrest) in your classpath.