If i were you,
I would first see if i'm familiar with the basic
java concepts..if im sure of myself...
I would sleep with the sun site and look through
Patterns(all kinds..for just an overall exposure to what exists)
JDBC,JNI,JNDI,JMS(though they look like many..with the right basic understanding u might even cover them in about a fortnight)
After this start with EJB again @ sunsite and go onto EJB patterns.
Download the java petstore and run the sample with focus on the app architecture and web flow. Research the
struts framework and command patterns for web-app flow from apache.org to familiarize with the 3-tier architecture systems,design flaws..etc.
Visit sites like serverside.com and drill more into the collective experience of the ppl implementing j2ee solutions.
Start on matching the object impedance with relational impedance(as a knowledge of both is very crucial for designing a scalable solution) from sites like
http://www.ambysoft.com/persistenceLayer.html#PersistenceWritings Hope my 2 cents helps u in making a roadmap.
All the best
[This message has been edited by Manjunath Reddy (edited July 27, 2001).]