So there has been some noise from Sun about how Google AppEngine is evil because it’s not supporting the complete set of classes in the JRE. I’m sorry Sun - I’m a Java programmer, and I think that argument is shit. I’d much prefer a partial Java implementation with well defined limitations than PHP, or Python or Ruby.
AFAIK, no one has posted a list of classes missing. I can’t be bothered doing that either, but I did manually take a look at package level. Here’s it looks like GAE/J is missing:
java.applet java.awt.* javax.activation javax.imageio.* javax.jws.* javax.management.* javax.naming.* javax.net.* javax.print.* javax.rmi.* javax.sound.* javax.swing.* javax.tools javax.xml.bind.* javax.xml.crypto.* javax.xml.soap javax.xml.stream.* javax.xml.ws org.ietf.jgss org.omg.*
From that list, I’d like to see javax.activation, javax.management and the remaining javax.xml.* and maybe javax.tools packages supported. The rest really don’t seem at all relevant to the AppEngine environment.