Your steps seem correct:
you can remove the existing jar, then produce ".class" files for your own version of the Adapter and put them in the "class" directory;
obviously, the whole directory tree where each class is in a directory representing its package should be copied.

There may be a typo in the names. For instance, the package and class names reported in your error message contain a couple of typos.

By the way, we expected more log related with an Adapter loading issue, with more insights on the error;
may you please show us the whole log?