Script to iterate through a list of jar files to add a file with contents corresponding to its respective jar file

Question

I currently have a folder of jar files :

a1.jar , a2.jar , a3.jar , ........ , a300.jar

that need to include a "test.xml" file inside of each jar file, which will have descriptors inside corresponding to the name of each jar file.

For example:

Inside of a1.jar should be a test.xml that looks like:

<Home>
<Group>
<ID>a1</ID>
</Group>
</Home>

I am trying to do this in linux.

My attempt:

#!/bin/bash 

jar_dir=.../jar

cd "$jar_dir" || exit

for file in *.jar; do    
 
****

add text.xml file that has  
<Home>
<Group>
<ID> $ name of jar file</ID>
</Group>
</Home>


****

done

Answer 1

It's just a matter of creating the XML file and then adding it to the JAR file.

$ cat so0597.sh
#!/usr/bin/env bash

# take in the jar directory as an argument, or use '.'
jar_dir=${1:-.}

cd "$jar_dir" || exit

for file in *.jar; do
    # create the file in /tmp using a HEREDOC
    cat <<EOX >/tmp/test.xml
<Home>
<Group>
<ID>$file</ID>
</Group>
</Home>
EOX

# add it using the 'jar' command
jar uvf $file -C /tmp test.xml

done

which results in:

$ ll
total 16
-rw-r--r-- 1 nobody nobody 684 Jun 18 21:12 a1.jar
-rw-r--r-- 1 nobody nobody 684 Jun 18 21:12 a2.jar
-rw-r--r-- 1 nobody nobody 684 Jun 18 21:12 a3.jar
-rwxrwxrwx 1 nobody nobody 201 Jun 18 21:10 so0597.sh

$ # JAR files are just ZIP files
$ # these JAR files are all identical
$ unzip -l a2.jar
Archive:  a2.jar
  Length      Date    Time    Name
---------  ---------- -----   ----
        0  06-18-2021 21:12   META-INF/
       69  06-18-2021 21:12   META-INF/MANIFEST.MF
        0  06-18-2021 20:53   bar
        0  06-18-2021 20:53   foo
        0  06-18-2021 20:53   test/
        0  06-18-2021 20:53   test/baz
---------                     -------
       69                     6 files

$ ./so0597.sh
adding: test.xml(in = 48) (out= 37)(deflated 22%)
adding: test.xml(in = 48) (out= 37)(deflated 22%)
adding: test.xml(in = 48) (out= 37)(deflated 22%)

$ unzip -l a2.jar
Archive:  a2.jar
  Length      Date    Time    Name
---------  ---------- -----   ----
        0  06-18-2021 21:12   META-INF/
       69  06-18-2021 21:12   META-INF/MANIFEST.MF
        0  06-18-2021 20:53   bar
        0  06-18-2021 20:53   foo
        0  06-18-2021 20:53   test/
        0  06-18-2021 20:53   test/baz
       48  06-18-2021 21:13   test.xml
---------                     -------
      117                     7 files

$ unzip -c a2.jar test.xml
Archive:  a2.jar
  inflating: test.xml
<Home>
<Group>
<ID>a2.jar</ID>
</Group>
</Home>