Sections are groups which start with Name: and have section-specific entries in them.
Capsule uses this for having platform-specific information about how to start.
Here's an example of using the API to get section information:
Main-Class: clojure.main
Name: Frank
Main-Class: frank.clojure.main
and
❯ clj
Clojure 1.10.3
user=> (require '[clojure.java.io :as io])
nil
user=> (io/input-stream "/tmp/MANIFEST.MF")
#object[java.io.BufferedInputStream 0x69ce2f62 "java.io.BufferedInputStream@69ce2f62"]
user=> (def mf (java.util.jar.Manifest. (io/input-stream "/tmp/MANIFEST.MF")))
#'user/mf
user=> (.getAttributes mf "Frank")
{#object[java.util.jar.Attributes$Name 0x2e3a5237 "Main-Class"] "frank.clojure.main"}
user=> (.getMainAttributes mf)
{#object[java.util.jar.Attributes$Name 0x2e3a5237 "Main-Class"] "clojure.main"}
user=> (.getEntries mf)
{"Frank" {#object[java.util.jar.Attributes$Name 0x2e3a5237 "Main-Class"] "frank.clojure.main"}}
