
been held in the 1.5 version of Java. Just as classes made under Java 1.4 won’t work
under 1.3, code that’s compiled with the Java 1.5 compiler won’t run on previous
versions of the JVM. Even if a program written with the JDK 1.5 doesn’t use any of
the latest features or APIs, it can’t run on systems that are running older JREs. This
lack of backward compatibility has long been an issue, but isn’t one that seems likely
to be rectified. Because of this, developers need to determine what version of the
JRE most of their customers are using, and then use the suitable JDK to develop
projects for that version.
Despite these issues, this doesn’t mean you should ...