Include file in Java project

Question

I have a code that runs routines inside Linux servers and access using public keys. When the project is on my pc (development), everything works because in the code I specify the location of the key that is on my machine, however when generating a jar (package for store) and running on another computer, the program does not find this key.

I already put the key inside the src/meProject folder and made the reference to the file and locally it worked, but on another machine not.

I researched getresources but I still couldn’t.

I refer to the file as any string:

String privateKey = "Diretorio\id_dsa.ppk";

What would be the correct way to attach this key to my project so that it runs on any machine?

Answer 1

You are making reference to the directory via hard coded, this is not a good idea, in different environments this may not work, for example, Windows uses the so-called "backslash" to separate directories, while linux uses the "normal toolbar".

Yaml

The good practice in this case is the use of a configuration file, my preference is the yaml, some languages, like python, have packages for parse yaml, I don’t know if you have in java, but has this tutorial.

Example of a yaml configuration file:

linux:
  privateKey: /home/user/keys/id_dsa.ppk  
  ...

windows:
  privateKey: c:\path\keys\id_dsa.ppk  

So in your app just identify the environment and read the privatekey variable from the correct key (linux or windows).

Environment variable:

Another option within good practices is the use of environment variables. Your app would have to read an environment variable that points to the file path, example of creating variables:

Creating environment variable in linux:

export PKEY=/home/user/keys/id_dsa.ppk

To create environment variables in windows, see this link.

Obs.:
Using environment variables may seem easier for the developer side, but in my opinion the configuration file is safer and more flexible.