connection to mysql server failed

Question

x1.instance3650.db.xeround.com-nino_db 
[chatserver.sql.MySqlConnection.rehash()]   
this is con null [.()]   
connection to MySQL server failed 
com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException:  
Cannot load connection class because of underlying exception: 
'java.lang.NumberFormatException: For input string: "chatserver"'.  
[chatserver.sql.MySqlConnection.connect()]  
Exception in thread "AWT-EventQueue-0"  [.()] 
java.lang.NullPointerException [.()]  at   
chatserver.sql.MySqlConnection.ensureConnected(MySqlConnection.java:105) [.()]  at 
chatserver.sql.MySqlConnection.getServerConfig(MySqlConnection.java:936) [.()]  at 
chatserver.objects.ServerConfig.loadConfigFromSql(ServerConfig.java:57) [.()]  at 
chatserver.objects.ServerConfig.<init>(ServerConfig.java:49) [.()]  at 
chatserver.objects.Server.<init>(Server.java:36) [.()]  at 
chatserver.objects.Server.getInstance(Server.java:88) [.()]  at 
chatserver.main.ServerMain$1.run(ServerMain.java:24) [.()]  at 
java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209) [.()]  at 
java.awt.EventQueue.dispatchEvent(EventQueue.java:597) [.()] at 
java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269) [.()]  
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184) [.()]  
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174) [.
()]  at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169) [.()]  at 
java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161) [.()]  at 
java.awt.EventDispatchThread.run(EventDispatchThread.java:122) [.()]

This is thrown by the following block of code..

try {
     //conn = DriverManager.getConnection ("jdbc:mysql://localhost:chatserver");
     // Joshua - change
     // dbPassword = "";
     conn = DriverManager.getConnection("jdbc:mysql://" + dbHost + ":"
                  + dbPort + "/" + dbDatabase + "?" + "user=" + dbUser
                    + "&"
                    + "password=" + dbPassword);
     lastMySqlActionTime = new Date().getTime();
} catch (SQLException e) {
     System.out.println("this is con "+conn);
     ServerLog.logError("connection to MySQL server failed "+e);
     return false;
}

I can get access to the databases through command prompt and use database...it is not throwing error any error in driver...

plz some one can help me..thank you

could you please format your question appropriately? The error message wrapped and indented correctly and the code as well. — glglgl, Jun 08 '12 at 08:36

mprabhat · Accepted Answer · 2012-06-08T08:37:06.397

1

From the stacktrace and code snippet available it seems your dbPort is chatserver, whereas port is an int like 3306, hence while parsing it as Integer it is failing and giving you NumberFormatException.

So instead of

conn = DriverManager.getConnection ("jdbc:mysql://localhost:chatserver")

try with this

conn = DriverManager.getConnection ("jdbc:mysql://localhost:3306/chatserver")

Complete connection string will look like below:

DriverManager.getConnection("jdbc:mysql://localhost:3306/chatserver",
                            "root", "root");

In above you can place your username, password, dbPort, databasename e.t.c.

Here I am assuming you want to connect to a schema named as chatserver

edited Jun 08 '12 at 08:37

answered Jun 08 '12 at 08:29

mprabhat

19,229
7
42
62

thank u mprabhat i sloved that problem but i ve encounter a new problem.I run that code n it runs smoothly in my netbeans but when i try to run the jar file of this particular project it gaves an error localhost-myblechat [chatserver.sql.MySqlConnection.rehash()] connection to MySQL server failed [chatserver.sql.MySqlConnection.connect()] Exception in thread "AWT-EventQueue-0"java.lang.NullPointerException atchatserver.sql.MySqlConnection.ensureConnected(MySqlConnection.java:100) chatserver.sql.MySqlConnection.getServerConfig(MySqlConnection.java:931) – nissal Jun 08 '12 at 09:15
glad, you can check this [link](http://stackoverflow.com/questions/4498047/export-jar-with-netbeans) for Jar Export in Netbeans or can start a new Question for that. – mprabhat Jun 08 '12 at 09:18
it worked mprabhat...jar files are created in dist folder...and i also found one jar file in my folder name "store" so i run it...so now when i run the jar file of my dist folder it worked....thank you 4 ur help... – nissal Jun 08 '12 at 09:32

score 0 · Answer 2 · answered Jun 08 '12 at 08:30

0

I think the problem is in

conn = DriverManager.getConnection ("jdbc:mysql://localhost:chatserver");

You get a NumberFormatException, because port number should be numeric.

answered Jun 08 '12 at 08:30

CamaroSS

453
6
15

score 0 · Answer 3 · answered Jun 08 '12 at 09:12

Look at my code below, and try to implement it as its here.... i hope it will run smoothly.. Once you start getting your desired query result, modify it to your heart content for further R&D.

Please change the password and username in this program

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.sql.ResultSetMetaData;

import java.sql.SQLException;

import java.sql.Statement;

import java.util.Vector;

import javax.swing.JTable;

import com.my.views.*;


public class DBDiary {

    Connection conn;
    EntryDisplay entryD;


    public DBDiary(){

        this.getConn();

    }

    public Connection getConn(){

        try {
            conn = getConnection();

        } catch (SQLException e) {

            System.out.println("Connection Couldnt be Obtained");
        }
           return conn;
    }


    public static Connection getConnection() throws SQLException {

        String drivers = "com.mysql.jdbc.Driver";
        String url = "jdbc:mysql://localhost:3306/test";
        String username = "root";
        String password = "root";

        System.setProperty(drivers,"");

        return DriverManager.getConnection(url,username,password);

    }

    public void createTable() {

        Statement stat = null;
        String sql = "create table items(item varchar(30), cost DOUBLE(12,3),day integer,month varchar(15), year integer);";
        if (conn != null){

            try {

                 stat = conn.createStatement();

            } catch (SQLException e) {

                System.out.println("Connection Couldnt be Obtained");
            }

            if (stat != null){

                try {
                    stat.executeUpdate(sql);
                } catch (SQLException e) {
                    //System.out.println("Table already Exists");
                }       
            }

        }
    }


    public void addItems(String item, double cost,int day, String month, int year) {

        PreparedStatement pstat = null;

        String sql = "INSERT INTO ITEMS Values(?,?,?,?,?);";

        if (conn != null){

            try {

                 pstat = conn.prepareStatement(sql);


            } catch (SQLException e) {

                System.out.println("Connection Couldnt be Obtained");
            }

        }

        if (pstat != null) {

            try {

                 pstat.setString(1, item);
                 pstat.setDouble(2, cost);
                 pstat.setInt(3, day);
                 pstat.setString(4, month);
                 pstat.setInt(5,year);
                 pstat.executeUpdate();

            } catch (SQLException e) {

                e.printStackTrace();
                System.out.println("Insertion of the entry was unsuccessful");
            }
        }


    }


    public static void main(String[] args) {

    DBDiary db = new DBDiary();
    db.createTable();
    db.addItems("Cards", 40.00,29, "Mar", 2012);


    }

connection to mysql server failed

3 Answers3