Reading the real BIG thread for the weblog "Why ABAP Performs Better in Portal Development than Java" - Hmmm I must say I was astonished about the many times mentioned opinion that there is no transport system in Java. Clearly this is true for most of the Java development systems, as Java IDE's mostly come with source revision systems and there it ends.
Not so with SAP's Java environment delivered with SAP NetWeaver. This actually does have NetWeaver Development Infrastructure (NWDI, formerly JDI) which definitely already comes very close to the ABAP transport system.