When stepping into class instantiation, eclipse debugger goes to native code

Eclipse has a step filter preference in the Java debugger preferences. Its default preference filters out java.lang.ClassLoader, however this wasn't working. This might have something to do with recently having installed and switched to using jre7. To solve my problem I added a filter to step through any code in the java.lang package.

I think the ClassNotFoundException is just happening as a part of class loading -- the problem is that you have a breakpoint set to trigger when those exceptions are thrown. My guess is that your version of Eclipse has this breakpoint on by default, whereas the old one didn't.

Check out this link, which reports a similar problem and provides the solution, which is just to disable that breakpoint.

(In the interest of teaching to fish and all that, the google search term was "eclipse debugger launcher$appclassloader".)