A good example of using Java with 7-Zip-JBinding to uncompress 7z files is available in the StackOverflow thread Decompress files with .7z extension in java. Dark Knight ‘s response indicates ...

Use a simple Automator workflow to compress multiple files into multiple archives.

Packaging Java programs as JAR files There's nothing particularly interesting about a JAR file. At its heart, it's simply a mechanism to compress multiple files. A JAR file uses exactly the same ...