webdav starter question

hi, 
    i have just started using webdav...
    i have following queries...
    1) how the request from a client is mapped to webdav server...
    2) can someone explain about webdav servlet.java
    3) i want to add my own implementations like when i copy a folder, a log should also get generated .... how can i do that....

    Please also tell me any technical book on webdav...
thanks 
regards,
yogi