问题描述
Glassfish服务器日志中出现以下错误
from the Glassfish server log am getting an error below
警告:RAR8054:为池[hrms/connectionPool]创建未池化的[test]连接时发生异常，为null警告:RAR8054:为池[hrms/connectionPool]创建未池化的[test]连接时发生异常，null
WARNING: RAR8054: Exception while creating an unpooled [test] connection for pool [ hrms/connectionPool ], nullWARNING: RAR8054: Exception while creating an unpooled [test] connection for pool [ hrms/connectionPool ], null
在使用jsp和struts框架实现jdbc mysql数据源和连接池时遇到问题.请帮忙.
am getting a problem in implementing jdbc mysql datasource and connection pooling using jsp and struts framework. please help.
显示代码....
/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
package database;
/**
*
* @author LenasalonM01
*/
import java.sql.Connection;
import java.sql.Statement;
import java.sql.ResultSet;
import javax.naming.InitialContext;
import javax.sql.DataSource;
import javax.swing.JOptionPane;
public class database {
private Connection connect;
private Statement statement;
private ResultSet resultset;
private InitialContext context;
private DataSource datasource;
public void connection() {
try {
// load driver
Class.forName("com.mysql.jdbc.Driver").newInstance();
// initialize context
context = new InitialContext();
// datasource path
datasource = (DataSource) context.lookup("jdbc/hrms");
// connect to datasource
connect = datasource.getConnection();
// create statement from connection made
statement = connect.createStatement();
} catch (Exception e) {
JOptionPane.showMessageDialog(null, e.getMessage());
}
}
public void disconnect() {
try {
if (resultset != null) {
resultset.close();
}
if (connect != null) {
connect.close();
}
if (context != null) {
context.close();
}
} catch (Exception e) {
JOptionPane.showMessageDialog(null, e.getMessage());
}
}
public boolean checkValid(String query) {
try {
connection();
resultset = statement.executeQuery(query);
if (resultset.next()) {
return true;
} else {
return false;
}
} catch (Exception e) {
JOptionPane.showMessageDialog(null, e.getMessage());
return false;
}
}
public ResultSet fetchdata(String query) {
try {
connection();
resultset = statement.executeQuery(query);
disconnect();
return resultset;
} catch (Exception e) {
return resultset;
}
// return resultset;
}
}
推荐答案
MySQL守护程序是否已启动并正在运行?您可以使用命令行客户端连接到服务器吗?如果没有，请启动服务器，然后再次重新运行您的应用程序.
Is the MySQL daemon up and running? Can you connect to the server using the command line client? If not, start the server and re-run your application again.
我建议您将数据库代码与用户界面内容分开.您会后悔有一天将两者结合在一起.
I would advise you to separate your database code from user interface stuff. You'll regret combining the two the way you have someday.
这篇关于使用Struts时jdbc mysql数据源连接错误的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！