Oracle's "Http Authentication" page from the Java SE 6 documentation says that "if you are running on a Windows machine as a domain user, or, you are running on a Linux or Solaris machine that has already issued the kinit command and got the credential cache" then the instance passed to Authenticator.setDefault() "will be completely ignored".
This matches what I observed: setting up an HTTP or HTTPS connection on a Windows system to host X always passes the credentials for host X from the 'Windows Credentials' of the 'Windows Vault', as seen in my Windows 7 'Credential Manager' Control Panel page.
However, in my use case I don't want to use any credentials which might be stored by Windows, but instead I always want to use credentials I explicitly specify in the code.
Is there a way to override the documented behavior, i.e., is there a way to ignore the credentials stored by Windows?
Update: If not, could someone point me to a place in the Java SE 6 source code where I can see that the stored Windows credentials cannot be ignored?