Accessing properties file in a jar file from code in the same jar file

[Amol Kshirsagar]

Hi All,

I am sort of stuck with an implementation that I have been asigned.It is a standalone runnable jar that I have to create from an eclipse project. This eclipse project runs fine when run from Eclipse IDE. But when I export it as a runnable jar and then when I run the jar using :

File f =new File("abc.properties");

the code searches in the folder in which I have placed my runnable jar and NOT WITHIN the jar itself.I want to ideally put evrythin in the jar file and then run only the jar file from command prompt.Because of this issue I have to keep the properties file with the jar file in the same folder so that my File IO picks it up.


Can anyone please suggest me a solution to put it in the jar and still use it.

[Jaikiran Pai]

You can use the getResource() or getResourceAsStream() APIs on the ClassLoader class to fetch resource. All you have to do is use the correct classloader and based on what you say, I think using the classloader of the class (@see Class.getClassLoader() API) from where you are looking up this file should work.

[E Armitage]

Put the file on the classpath and load the properties using

properties.load(this.getClass().getResourceAsStream("abc.properties"));

[Rob Spoor]

Slightly better, because it closes the InputStream:

try (InputStream in = this.getClass().getResourceAsStream("abc.properties")) {
    properties.load();
}

[Amol Kshirsagar]

Hi ,

Really appreciate your quick response. I got the solution.I used

Properties properties = new Properties();
properties.load($MyClassName$.class.getResourceAsStream("/Environment.properties"));

Here '/' was the main catch since the properties file was placed immediately in the jar file and not under any folder in the jar.

Once again thanks for your help !!!

[E Armitage]

Rob Spoor wrote:Slightly better, because it closes the InputStream:

try (InputStream in = this.getClass().getResourceAsStream("abc.properties")) {
    properties.load();
}

Much better actually.
Amol you should check the API specs for that Properties.load method which say

The specified stream remains open after this method returns.

and therefore use the try with resources if on Java 7 or close the stream in a finally if on an earlier Java version.