如何从可执行jar文件访问derby数据库？

Question

I am using java and derby database. I built derby database in netbeans IDE. I have created a executable jar file using clean and build option.

While running the project in netbeans, it connect to database goodly. But if I run executable jar file, it doesn't connect to the database.

Help me to create a executable jar file with derby database, It should run on any other system.Part of coding to connect database is

String str = textarea.getText();
    Class.forName(driver).newInstance();
    conn = DriverManager.getConnection(url+dbName,userName,password);
    String stm="select url from pingatabl where functn=?";
    PreparedStatement st = conn.prepareStatement(stm);
    st.setString(1, str);
     //Excuting Query
    ResultSet rs = st.executeQuery();
    if (rs.next()) {
    String s = rs.getString(1);
    //Sets Records in frame
    JFrame fm = new JFrame();
    fm.setVisible(true);
    fm.setSize(500,750);
    JEditorPane jm = new JEditorPane();
    fm.add(jm);
    jm.setPage(ClassLoader.getSystemResource(s));

Answer 1

You are as novice as I was 2 years ago. The thing is that you have not installed derby at all. See, Derby is a database server and netbeans has its own version of derby. So, it runs when made to run inside Netbeans but does not start when run from an executable file. So, first, install derby from https://db.apache.org/derby/ and then start the server and then you can access it from the executable file. Also, I would recommend you to use MySQL server instead of derby. But, you can always use derby.