Форум программистов [Powered by Invision Power Board]

Код


package test;

import java.sql.Connection;
import java.sql.SQLException;

import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import javax.sql.*;

public class ConnectionFactory {

    private static DataSource pool;
    private static Context env = null;    
    private static ConnectionFactory cdb;

    private ConnectionFactory() {

    }

    //Singleton
    public static ConnectionFactory getInstance() {
        if(cdb == null) {
            cdb = new ConnectionFactory();
        }
        return cdb;
    }
    
    //pool
    static {
      try{
          
            env = (Context) new InitialContext().lookup("java:comp/env");
            pool  = (DataSource) env.lookup("datasource");
            if (pool == null)
            throw new NamingException("'datasource' is an unknown DataSource");
            
       } catch (NamingException e) { 
       
           e.printStackTrace();
    
       }
    }
    
      //metod return pool
      public Connection getConnection() throws SQLException{
            Connection conn = pool.getConnection();
            return conn;
          }

}

Код


package test;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import java.sql.*;
import java.util.logging.Logger;
import javax.sql.*;

import model.Model;

/**
 * Servlet implementation class Data
 */
@WebServlet("/Data")
public class Data extends HttpServlet {
    private Logger log = Logger.getLogger(Data.class.getName());
    
     DataSource pool;
     Connection conn = null;
     Model m = new Model();
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public void init() throws ServletException {
     
     ConnectionFactory c = ConnectionFactory.getInstance();    
      
        try {
                conn = c.getConnection();
                
            } catch (SQLException e) {
                
                log.info("Error!");
            } 
            /*finally {
                try{ conn.close(); } catch(Exception e) { }
            }*/

    }

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        
        response.setContentType("text/html");
        PrintWriter out = response.getWriter();
        
        out.println("<html>");
        out.println("<head>");
        out.println("<meta http-equiv=\"refresh\" content=\"15\">");
        out.println("<title>POOL</title>");
        out.println("<link REL=\"stylesheet\" TYPE=\"text/css\" HREF=\"css/style.css\">");
        out.println("</head>");
        out.println("<body>");

        out.println("Hello!");
        out.println("<BR>");
        
        // Вывод данных из БД
        out.println(m.show(conn, "user"));
        
        
        out.println("</body>");
        out.println("</html>");
        out.close();     
     
    }

}