Text and image files not included when exporting jar

Question

I've created a project which utilizes image files as well as a text file when executed. Both the text and image files are in my project folder before I exported the project into a runnable jar, but when I ran the jar from the command line, I got a filenotfound exception caused by the program typing to read from the text file. I unzipped the jar to double check and the image and text files weren't there.

package application;
import java.io.*;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.*;

import javafx.collections.FXCollections;

public class Data {
    private static Data instance=new Data();
    private Map<String,String> saveEntries = new HashMap<>();
    private static String fileName = "ResponseData";

public static Data getInstance() {
    return instance;
}

public void exitSave() throws IOException {
    Path path = Paths.get("ResponseData");
    Iterator<Map.Entry<String, String>> iter = saveEntries.entrySet().iterator();
    BufferedWriter bw = Files.newBufferedWriter(path);
    try {
        while(iter.hasNext()) {
            Map.Entry<String, String> entry = iter.next();
            bw.write(String.format("%s\t%s", entry.getKey(),entry.getValue()));
            bw.newLine();
        }
    } catch (IOException e) {
        new FileNotFoundException("Error when saving data");
    }finally {
        if(bw!=null)
            bw.close();
    }
}



public void updatedSaveEntry(String input, String response) {
    saveEntries.put(input, response);
}

public Map<String,String> getSaveEntries(){
    return this.saveEntries;
}

public void setEntry(Map<String,String> map) {
    Iterator<Map.Entry<String, String>> iter = map.entrySet().iterator();
    while(iter.hasNext()) {
        Map.Entry<String, String> entry = iter.next();
        saveEntries.put(entry.getKey(), entry.getValue());
    }
}


public void loadEntries() throws IOException{
    saveEntries = FXCollections.observableHashMap();
    Path path = Paths.get(fileName);
    BufferedReader br = Files.newBufferedReader(path);
    String line;
    try {
        while((line=br.readLine())!=null&&!line.trim().isEmpty()) {
            String[] parts = line.split("\t");
            saveEntries.put(parts[0], parts[1]);
        }
    }finally {
        if(br!=null) {
            br.close();
        }
    }

}

}

Eclipse Runnable Jar Export

Project Folder

Answer 1

Your program is trying to read the file from your local file system and not from the jar file. So it should indeed not be included in the jar file. The program is expecting the file in the current working directory where you execute your program and that can be different if you run your project within Eclipse or if you execute the exported jar file.

Answer 2

If you are both reading and writing to a file, then locating this file in the application jar is not appropriate as mentioned in the other answer: you should persist your data at an external location.

However, it is usual to keep the read-only resources files (such as images) in the jar. If you want to keep this approach for the images and possibly other resources, you are facing two problems:

1. Getting Eclipse to include the file in the jar using the Export Runnable Jar feature.

2. Finding the file in the jar

Including the file

The simplest is probably just to place the file in a source folder. In your project, do New -> Source Folder, give it a name (e.g., "resources"), and move your file there. Normally, if you re-run the export, the file should be in the jar.

Finding the file

Files in jar are accessed differently. See the accepted answer to Reading a resource file from within jar. Note that you don't need to include the name of your resource folder in the path, as this file will be placed at the root of your jar (you can verify this by unpacking it).