I'm planning to write a web application on Google App Engine using Java. Each user needs to log in first to see all the secure account information. I have the following questions:
Is Google Users Service equal to SSL? I use Google Users Service to authenticate the user. After redirecting from the Google Accounts sign-in page to my web application, are my web pages SSL-protected (I believe so because all these Google account information will be available to my page after the redirection)? If so, there seems to be no need for me to apply a CA certificate to enable SSL.
Is there any e-commerce open source project for Google App Engine using Java? I see answers for Python only.