follow these rules for Sun products, and third-party products must follow the
same rules for Java Plug-in to make reliable decisions about whether an extension
is up-to-date or not:
Specification-Version string will be of the form:
n3 are integers,
is the major version number, and optional
n3 is the minor
version number (also referred to as the maintenance version number).
Implementation-Version will be of the same form initially
n4n5to indicate a patch version number (also referred to as the update version number)
-") a milestone name (
rc...), which may also include a trailing integer number (
Both patch version number and milestone name may not be used together in the
The general form is as follows:
n3 ...), letters, dots,
hyphens, and underscores , may be used in the version format as described above;
no other characters ("
...) are allowed.
Note that the
numbers are in theory independent, though in practice they are often in sync
with each other.
While these are the rules, it is always a good idea when using a third-party
JAR to examine its
MANIFEST.MF file to see
what actual values are in it. If it does not follow these rules, you may need
to change your applet
or alter the extension