[Broker-J] Code cleanup: immutable fields, static inner classes, long literals

Following issues are covered with this JIRA:

1. Private fields whose values never change once they are initialized either in the declaration of the field or by a constructor should be marked as final. This aids in converting existing classes to immutable classes.

2. A non-static inner class has a reference to its outer class, and access to the outer class' fields and methods. That class reference makes the inner class larger and could cause the outer class instance to live in memory longer than necessary.

3. There are many places in the broker code where long literals end with lowercase 'l' character mimicking the '1'. They should be replaced with uppercase 'L'.