Question

我正在尝试第一次创建J2EE应用程序。

我在MySQL上创建了我的数据库，现在我想用我的应用程序在屏幕上获取所有数据。

问题是：当我想连接MySQL数据库上的应用程序时，我有错误：

java.sql.SQLException: Cannot create PoolableConnectionFactory (Could not create connection to database server. Attempted reconnect 3 times. Giving up.)

我正在使用：

VirtualBox VM 5.0
Windows 7
EasyPHP with MySQL（5.7.11 x86）
JDBC：MySQL Connector 5.1.31
Eclipse

server.xml（在c：/ serveur / tomcat / conf /中）

<Resource name="UserDatabase" auth="Container"
              type="org.apache.catalina.UserDatabase"
              description="User database that can be updated and saved"
              factory="org.apache.catalina.users.MemoryUserDatabaseFactory"
              pathname="conf/tomcat-users.xml" />


          <!-- JNDI de la base nouvellebd -->
<Resource name="base_test" 
    type="javax.sql.DataSource" 
    password="" 
    driverClassName="com.mysql.jdbc.Driver" 
    maxIdle="2" 
    maxWait="500" 
    username="root" 
    url="jdbc:mysql://127.0.0.1/nouvellebd?autoReconnect=true"  
    maxActive="500"
/>

我的“上下文”（在conf / catalina / localhost / ProjetServlet.xml中）：

<Context path="/ProjetServlet" 
    reloadable="true" 
    docBase="c:\MonEspace\ProjetServlet" 
    workDir="c:\MonEspace\ProjetServlet\work" >
    <ResourceLink
        name="base_test"
        global="base_test"
        type="javax.sql.DataSource"/>
</Context>

我可以用CMD连接自己的MySQL服务器，没有问题。
JDBC文件添加在c：/ server / lib

我的代码（AffichePersonne.java）：

package mesServlets;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.Statement;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.sql.DataSource;

public class AffichePersonne extends HttpServlet {


    Connection BD;
    DataSource ds;

    protected void doGet(HttpServletRequest req, HttpServletResponse resp) 
            throws ServletException, IOException {
                try {
                BD=ds.getConnection();
                Statement s = BD.createStatement();
                ResultSet r = s.executeQuery("select * from personne");
                PrintWriter out=null;
                resp.setContentType("text/html");
                out = resp.getWriter();
                out.println("<html>");
                out.println("<head><title> Test servlet </title></head>");
                out.println("<body>");
                out.println("Contenu de la table personne <BR>");
                out.println("<table>");
                out.println("<TR>");
                out.println("<TD>Nom</TD>");
                out.println("<TD>Prénom</TD>");
                out.println("</TR>");
                while (r.next()) {
                    out.println("<TR>");
                    out.println("<TD>");
                    out.println(r.getString("nom"));
                    out.println("</TD>");
                    out.println("<TD>");
                    out.println(r.getString("prenom"));
                    out.println("</TD>");
                    out.println("</TR>");
                    }
                out.println("</table>");
                out.println("</body>");
                out.println("</html>");
                r.close();
                s.close();
                BD.close();
                s = null;
                r = null;
            } catch (java.sql.SQLException ex) {
                System.out.println("Erreur d'exécution de la requête SQL \n"+ex);
            } 
        }

    public void init() throws ServletException  {
        try {
        System.out.println("Récupération du contexte");
        Context initCtx = new InitialContext();
        System.out.println("lookup de env");
        Context envCtx = (Context) initCtx.lookup("java:comp/env");
        System.out.println("lookup de base_test");
        ds=(DataSource) envCtx.lookup("base_test");
        //System.out.println("Datasource chargée");
        }
        catch(Exception er) {
            System.out.println("Erreur de chargement du contexte " + er);
        }   }

}

“mapping”（web.xml）：

<?xml version="1.0" encoding="ISO-8859-1"?>

<!DOCTYPE web-app
    PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
    "http://java.sun.com/dtd/web-app_2_3.dtd">
<web-app>
    <display-name>Mes servlets</display-name>
    <description>
      Premi�res servlets
    </description>
    <servlet>
        <servlet-name>ServletHello</servlet-name> 
        <servlet-class>mesServlets.HelloServlet</servlet-class> 
        <description>Servlet d'essai</description> 
    </servlet>
    <servlet-mapping> 
        <servlet-name>ServletHello</servlet-name>
        <url-pattern>/hello</url-pattern> 
    </servlet-mapping>  

    <servlet>
    <servlet-name>ServletBD</servlet-name> 
    <servlet-class>mesServlets.AffichePersonne</servlet-class> 
    <description>Servlet d'essai de la connection BD</description> 
    </servlet>

    <servlet-mapping> 
    <servlet-name>ServletBD</servlet-name>
    <url-pattern>/essaibd</url-pattern> 
    </servlet-mapping>

</web-app>

非常感谢您的帮助:)

无法创建PoolableConnectionFactory（无法创建与数据库服务器的连接）

0 个答案: