Look under cascades.java in the engine package. You will find (depending in the version) the info you are after; eg, code fragment
Code:
STYLES.put("all", STYLE_ALL);
STYLES.put("all-delete-orphan", STYLE_ALL_DELETE_ORPHAN);
STYLES.put("save-update", STYLE_SAVE_UPDATE);
STYLES.put("create", STYLE_CREATE);
STYLES.put("merge", STYLE_MERGE);
STYLES.put("lock", STYLE_LOCK);
STYLES.put("refresh", STYLE_REFRESH);
STYLES.put("replicate", STYLE_REPLICATE);
STYLES.put("evict", STYLE_EVICT);
STYLES.put("delete", STYLE_DELETE);
STYLES.put("delete-orphan", STYLE_DELETE_ORPHAN);
STYLES.put("none", STYLE_NONE);