The Apache Ant team regularly gets complaints that this task in generating invalid manifests.
By and large, this is not the case: we believe that we are following the specification to the letter.
If you find that Ant generates manifests incompatible with your runtime, take a manifest it has built, fix it up however you need and switch to using the Creates or replaces the file MANIFEST. Note that the Built-By attribute will take the value of the Ant property $.
(Version and vendor information is contained in special headers that you can add to a JAR file's manifest.
The Java Archive (JAR) format consolidates multiple files into a single archive file, which contain Java classes and other auxiliary files (such as properties files). Accordingly, when you use a JAR file, you inherit offerings of the ZIP format, including lossless data compression and archiving.
Archiving class files and compressing them allows you to distribute applications quickly in a network environment.
We'll cover the basics of using the JAR tool before delving a bit deeper into some more extended offerings of the tool later in this article.
J2ME runtimes appear to be particularly troublesome. MF that contains package version identification for the package Manifest-Version: 1.0 Built-By: bodewig Created-By: Apache Ant 1.9 Name: common Specification-Title: Example Specification-Vendor: Example Organization Implementation-Vendor: Example Corp.This task forms an implicit File Set and supports most attributes of elements.You can also use nested file sets for more flexibility, and specify multiple ones to merge together different trees of files into one JAR. An example use of this is provided in the Zip task documentation.I just created an executable jar file for a Java client-side application.I hadn't done this in a while, and I always forget about the option to include a manifest file in the jar file.