Revert "Add the demo code for class and field"

This reverts commit 1177a4aae0fe62c0a7ece16a54bae32176cbf7ce.
Revert "refact code"

This reverts commit c1e8fbbf4acd603dff36680a613d60547dba86ab.
Revert "Init the code for reflect demo"

This reverts commit 0483f2e1da0242b66f9c6845172e036af1e34007.
Revert "Initial commit"

This reverts commit 2d9c160bf9fe36c4222e39e22ce1fcd552a20b12.