JDBC Connection Problem

[venu jayaram]

Hi friends,

I written one JDBC connection class. While running it's showing Exception.
i am using netbeans6.1 and jboss4.0.4 server. i added the driver also that is my-connector-java-5.1.

please help me to solve this problem

  
/*
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package com.myapp.struts;
import java.sql.*;
 

public class Database {
 
     public static Connection getConnection() {
        Connection connection=null;
       // ResourceBundle rb = ResourceBundle.getBundle("Soremi");
        String driver= "com.mysql.jdbc.Driver";
        String URL = "jdbc:mysql://mysql.local.com:3306/venu";  
        String username = "root";
        String password = "root";
       try {
            if(driver == null || URL == null) {
                throw new Exception("Driver class or Driver URL should not be null");
            }
            Class.forName(driver);
            connection=DriverManager.getConnection(URL,username,password);
        }
        catch(Exception e) {
            e.printStackTrace();
        }
        return connection;
    }
    public static void main(String args[])
    {
        try
        {
            Connection con = getConnection();
            System.out.println("got connection");
            con.close();
            System.out.println("got connection");
        }
        catch(Exception e)
        {
e.printStackTrace();
        }
    }
}
 
 

Exception are


init:
deps-module-jar:
deps-ear-jar:
deps-jar:
compile-single:
run-main:
com.mysql.jdbc.CommunicationsException: Communications link failure

Last packet sent to the server was 0 ms ago.
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1070)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2103)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:718)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:298)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:282)
at java.sql.DriverManager.getConnection(DriverManager.java:525)
at java.sql.DriverManager.getConnection(DriverManager.java:171)
at com.myapp.struts.Database.getConnection(Database.java:25)
at com.myapp.struts.Database.main(Database.java:36)
got connection
Caused by: java.net.UnknownHostException: mysql.local.com: mysql.local.com
at java.net.InetAddress.getAllByName0(InetAddress.java:1128)
at java.net.InetAddress.getAllByName0(InetAddress.java:1098)
at java.net.InetAddress.getAllByName(InetAddress.java:1061)
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:243)
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:280)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2026)
... 7 more
java.lang.NullPointerException
at com.myapp.struts.Database.main(Database.java:38)
BUILD SUCCESSFUL (total time: 20 seconds)

[Paul Sturrock]

You have defined a JDBC URL that will try to connect the the DNS mysql.local.com. I'm guessing this doesn't exist. Shouldn't it be "localhost"?

[venu jayaram]

Then please tell me what have to do, I want to interact with database using JDBC through Struts application.. please asap...


Thanks and Regards
Venu J

[Peter Johnson]

What is the name of the host running MySQL? Change the database URL to use that host name (instead of "mysql.local.com"). If the MySQL database is running on the same host as your code, then use:

String URL = "jdbc:mysql://localhost:3306/venu";

[venu jayaram]

thank you very Peter Johnson