Java .jar无法启动，因为从文件加载了jcombobox数据

Question

I am beginner with Java and I have tried to make my app better. So I have a method to fill the jcombobox with items from text file. The method is

private void fillComboBox(JComboBox combobox, String filepath) throws FileNotFoundException, IOException {

    BufferedReader input = new BufferedReader(new FileReader(filepath));
    List<String> strings = new ArrayList<String>();
    try {
        String line = null;
        while ((line = input.readLine()) != null) {
            strings.add(line);
        }
    } catch (FileNotFoundException e) {
        System.err.println("Error, file " + filepath + " didn't exist.");
    } finally {
        input.close();
    }

    String[] lineArray = strings.toArray(new String[]{});

    for (int i = 0; i < lineArray.length - 1; i++) {
        combobox.addItem(lineArray[i]);
    }

}

And I am using it correctly

fillComboBox(jCombobox1, "items");

the text file with items is in my root directory of netbeans project. It works perfectly when running the app from netbeans. But when I build the project and create .jar file. It does not run. I tried to run it from comand line. This is what I got.

java.io.FileNotFoundException: items(System cannot find the file.)

How to deal with this? I didnt found anything. I dont know where is problem since it works nice in netbeans. Thank you very much for any help.

Answer 1

Is the .jar file in the same root directory?

Your exported .jar file might be working from a different directory, and not be able to find the text file.

Try placing the exported Jar in the same directory as the text file.

My example:

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import javax.swing.JComboBox;
import javax.swing.JOptionPane;

public class test {

    public static void main(String[] args) throws FileNotFoundException, IOException{
        JComboBox box = new JComboBox();
        fillComboBox(box, "C:\\path\\test.txt");
        JOptionPane.showMessageDialog(null, box);

    }

    private static void fillComboBox(JComboBox combobox, String filepath) throws FileNotFoundException, IOException {

        BufferedReader input = new BufferedReader(new FileReader(filepath));
        List<String> strings = new ArrayList<String>();
        try {
            String line = null;
            while ((line = input.readLine()) != null) {
                strings.add(line);
            }
        } catch (FileNotFoundException e) {
            System.err.println("Error, file " + filepath + " didn't exist.");
        } finally {
            input.close();
        }

        String[] lineArray = strings.toArray(new String[] {});

        for (int i = 0; i < lineArray.length - 1; i++) {
            combobox.addItem(lineArray[i]);
        }

    }
}