Use property file in a JAR - properties

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?

Answer 1

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());
}
}
}