applet Mysql connection

[Bahadir Mert Uzan]

Yet another question from me

Here is my applet which runs well with netbeans but fails in a browser.

   package View;

import DataReader.Dealer;
import java.sql.*;


/**
 *
 * @author Nbahamut
 */
public class CardApplet extends javax.swing.JApplet {

    private Connection con;

    /** Initializes the applet CardApplet */
    public void init() {
        GamePanel panel = new GamePanel(new Dealer(read()).getViewDeck());
        panel.setSize(1000, 700);
        this.setSize(1000, 700);
        this.add(panel);
    }

    public Statement read() {
        Statement stm = null;

        try {
            Class.forName("com.mysql.jdbc.Driver");
            String url = "jdbc:mysql://localhost:3306/CofeeMe";
            con = DriverManager.getConnection(url, "root", "");
            System.out.println("URL:" + url);
            System.out.println("Connection:" + con);
            stm=con.createStatement();
        } catch (Exception e) {
            e.printStackTrace();
        }
        return stm;
    }
 

Basicly it connects to a database and send statement to another class to deal.

My problem when I run it doesn't relaize MySql-connector jar and makes an error

java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
at sun.plugin2.applet.Applet2ClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClassInternal(Unknown Source)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at View.CardApplet.read(CardApplet.java:36)
at View.CardApplet.init(CardApplet.java:26)
at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)

How can i force the jar to work? Thank you

[Paul Clapham]

Just like any other time when you get a ClassNotFoundException: make sure the class which wasn't found is in your classpath. I believe an applet's classpath is in the "archive" attribute of the HTML "applet" element.

[Bahadir Mert Uzan]

I am using a mysql connector and its an individual jar in libary folder.
Also I unrared the mysql connector char and put it into classes folder which I really dont want to do that
Is there a way out of this.

When i do the unraring part of connector I got a securty error.
If you can tell me away to solve these problems you basicly solved 80% of them.

these are the security errors.
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

Last packet sent to the server was 0 ms ago.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1074)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2120)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:723)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:46)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:302)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:282)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at View.CardApplet.read(CardApplet.java:39)
at View.CardApplet.init(CardApplet.java:27)
at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

Last packet sent to the server was 0 ms ago.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1074)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:335)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2043)
... 15 more
Caused by: java.net.SocketException: java.security.AccessControlException: access denied (java.net.SocketPermission 127.0.0.1:3306 connect,resolve)
at com.mysql.jdbc.StandardSocketFactory.unwrapExceptionToProperClassAndThrowIt(StandardSocketFactory.java:404)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:265)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:284)
... 16 more

[Ulf Dittmer]

Don't un-jar the driver file; instead, use the applet tag's archive attribute like Paul mentioned.

Applets can only make network connections to the host where they were served from. So the DB connection to 127.0.0.1 will only work if the applet page is on a page with address http://127.0.0.1/...