title: java.sql.SQLException: Access denied for user 'root'@'localhost' (using password: NO)
body: <p>I'm having troubles with my project , it involves <code>JDBC</code> and <code>Mysql</code> connection . </p>
  
  <p>When I do the following : </p>
  
  <pre><code>private Statement m_statement = null;               // statement 
  private Connection m_connection = null;             //  connection
  
  /**
   * Constructor #1 of the Database class
   * @throws ClassNotFoundException
   */
  public Database() throws ClassNotFoundException
  {
      try
      {
          Class.forName("com.mysql.jdbc.Driver");
          MysqlDataSource ds = new MysqlConnectionPoolDataSource();
          ds.setServerName("localhost");
          ds.setPort(3306);
          ds.setUser("root");
          ds.setPassword("");
          this.m_connection = ds.getConnection();
          this.m_statement = this.m_connection.createStatement();
      }
  
      catch (SQLException s)
      {
          System.out.println("SQL statement is not executed! 2!");
      }
  
  }
  </code></pre>
  
  <p>When I try to connect with the above code , the connection doesn't work ,here is the stacktrace : </p>
  
  <pre><code>java.sql.SQLException: Access denied for user 'root'@'localhost' (using password: NO)
      at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1074)
      at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4074)
      at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4006)
      at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:919)
      at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1694)
      at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1244)
      at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2397)
      at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2430)
      at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2215)
      at com.mysql.jdbc.ConnectionImpl.&lt;init&gt;(ConnectionImpl.java:813)
      at com.mysql.jdbc.JDBC4Connection.&lt;init&gt;(JDBC4Connection.java:47)
      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:411)
      at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:399)
      at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:334)
      at com.mysql.jdbc.jdbc2.optional.MysqlDataSource.getConnection(MysqlDataSource.java:443)
      at com.mysql.jdbc.jdbc2.optional.MysqlDataSource.getConnection(MysqlDataSource.java:141)
      at com.mysql.jdbc.jdbc2.optional.MysqlDataSource.getConnection(MysqlDataSource.java:111)
      at db.Database.&lt;init&gt;(Database.java:99)
      at controller.LoginPage.doGet(LoginPage.java:61)
      at javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
      at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
      at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
      at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
      at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:225)
      at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
      at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
      at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168)
      at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
      at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:927)
      at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
      at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
      at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1001)
      at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:579)
      at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310)
      at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(Unknown Source)
      at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
      at java.lang.Thread.run(Unknown Source)
  </code></pre>
  
  <p>How can I fix it ? </p>
  
  <p>Regards</p>