Use property file in a JAR

Question

After a lot of property file articles and comments I am really lost.

All I want is to retrieve values and to overwrite them - and I want to use that with a jar-file.

If I compile in eclipse it works perfectly but the moment I compile I got the famous "property file not found"-exception.

FileInputStream in = new   FileInputStream(ClassLoader.getSystemResource("client.properties").getPath()); 
Properties props = new Properties();
        props.load(in);
        in.close();

The exception I got is the following:

C:\Users\thomas\Desktop>java -jar erp_auer_client_v0_1.jar
java.io.FileNotFoundException: file:\C:\Users\thomas\Desktop\erp_auer_client_v0_
1.jar!\client.properties (Die Syntax f³r den Dateinamen, Verzeichnisnamen oder d
ie Datentrõgerbezeichnung ist falsch)
        at java.io.FileInputStream.open(Native Method)
        at java.io.FileInputStream.<init>(Unknown Source)
        at java.io.FileInputStream.<init>(Unknown Source)
        at global_functions.helperFunctions.getPathBARTENDEREXE(helperFunctions.
java:361)
        at client.programmeinstellungen.ProgrammEinstellungenManagement.<init>(P
rogrammEinstellungenManagement.java:59)
        at client.main.MainOverview$11.mousePressed(MainOverview.java:275)

The german part (Die Syntax f³r den Dateinamen, Verzeichnisnamen oder d ie Datentrõgerbezeichnung ist falsch) means "The syntax for the filename, directory name or disk name is wrong".

Do you have an idea what that could be?

You want to have your property file inside a jar (ok not a problem). Next you want to save values in this property file, right? I am not sure if that is possible, because a jar file is a self contained file and your application should run within that self contained file. I think you can run from Eclipse only because Eclipse does it from a folder where your project is stored and not from a real jar file... Does it make sense? — Rafa, Apr 04 '13 at 03:46
Thank you for your fast answer. But if so how / where can I store values permanently and can change it again? — tomier, Apr 04 '13 at 03:47
Anywhere outside the jar file: (1) You can hard code a given location; (2) You can just assume your property file will be on the same folder as your jar file; (3) You can add a parameter with the file location and work with it, something like: java -jar erp_auer_client_v0_1.jar -filePath c:\temp\client.properties — Rafa, Apr 04 '13 at 03:54
Since the file is started with double-Click on the jar-file the (2) would be the best. What is usually the correct way if you want to export a jar-program for user usage? — tomier, Apr 04 '13 at 03:58
I use maven, but if you are using Eclipse you can just export as a jar file and follow the Export Wizard. It should be alright. — Rafa, Apr 04 '13 at 04:01
What would be the right path for "FileInputStream in = new FileInputStream(ClassLoader.getSystemResource("client.properties").getPath());" when I want to have option (2) same folder? (Off topic) How do you start an application over maven? What is the difference? Ah, I mean export — tomier, Apr 04 '13 at 04:14
If you use (2), then it is not a SystemResource anymore see: http://stackoverflow.com/questions/320542/how-to-get-the-path-of-a-running-jar-file — Rafa, Apr 04 '13 at 04:21
Maven is a dependency tool, you can build a project and create a jar (or war, ...). However, you need to learn how to create a descriptor (pom.xml) and the command line. It might take some time for you to learn... — Rafa, Apr 04 '13 at 04:25
Ok. Thank you very much for your help. I can't +1 you because it's just a comment. — tomier, Apr 04 '13 at 16:14
Hey, the problem is now that the same jar file is NOT working on another PC. I don't see why but it doesn't create the folder on the other PC. — tomier, Apr 05 '13 at 20:22

score 0 · Answer 1 · answered Apr 07 '13 at 16:07

Alright, I tried it myself and realized that it is a little more trickier than I thought initially. However, I think that in your scenario you can just use something like bellow. I tested in windows and linux and worked fine for me:

package mypackage;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.OutputStream;
import java.net.URISyntaxException;
import java.util.Date;
import java.util.Properties;

public class MyMainClass {

    public static void main(String[] args) throws URISyntaxException {
        /*
         * 
         * MyMainClass.class.getProtectionDomain().getCodeSource().getLocation().toURI().getPath();
         * In Linux it returns null
         * 
         * ClassLoader.getSystemClassLoader().getResource(".").getPath() + "MyProperty.properties";
         * In Linux it returns {JRE_PATH}/lib/ext/pulse-java.jar
         * In Windows it returns {JAR_FILE_PATH}
         */

        String propertyFilePath = "MyProperty.properties";
        Properties props = new Properties();
        try {
            FileInputStream in = new   FileInputStream(propertyFilePath); 
            props.load(in);
            in.close();
        } catch (Exception e) {
            File f = new File(propertyFilePath);
            System.err.println("Could not read file: " + f.getAbsolutePath());
        }

        System.out.println("Fetching property value of [now]: " + props.get("now"));
        String now = new Date().toString();
        System.out.println("Storing property [now]: " + now);
        props.setProperty("now", now);

        try {
            OutputStream out = new FileOutputStream(propertyFilePath); 
            props.store(out, "Saving value of [now]");
        } catch (Exception e) {
            File f = new File(propertyFilePath);
            System.err.println("Could not write file: " + f.getAbsolutePath());
        }
    }
}

Use property file in a JAR

1 Answers1