Java Reference
In-Depth Information
Appendix A. Application Evolution
With every passing hour our solar system comes 43,000 miles
closer to globular cluster M13 in the constellation Hercules, and still
there are some misfits who continue to insist that there is no such
thing as progress.
Ransom K. Ferm
The Java platform has undergone a number of changes since it was first
introduced, but none more significant than those that occurred with the
5.0 release. While in general we try to avoid issues concerning the evolu-
tion of the platform, it is impossible to ignore those issues now. For some
time to come, there will be applications and libraries that still comply with
the older 1.3 version of the platform (as documented in the third edi-
tion of this topic), those that support the additional features introduced
in the 1.4 release, and finally those moving forward to take full advant-
age of the new features of the 5.0 release. The technical issues involved
in application evolution and migration can be complex, and many of the
changes to the language and libraries for the 5.0 release were designed
with backward compatibility and migration in mind. A full coverage of the
technical issues, let alone the management and logistics issues involved,
is beyond the scope of this topic, but we do want to highlight a couple of
areas for your consideration.
The first section gives a brief overview of how the compiler and virtual
machine can deal with different versions of the language and runtime.
Next, we look at some ways of dealing with the different dialects that
language changes produce, using assertions as an example. Finally, we
look at some of the issues involving the integration of generic and non-
generic code.
 
Search WWH ::




Custom Search