package com.util;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
public class DBManager {
private String driver="com.mysql.jdbc.Driver";
private String
url="jdbc:mysql://localhost:3306/hwglxt";
private String username="root";
private String password="admin";
public static Connection connection =null;
private static DBManager dbManager=null;
private DBManager()
{
try
{
Class.forName(driver);
connection=DriverManager.getConnection(url, username, password);
}
catch (Exception e) {
System.out.println("數據庫連接異常");
}
}
public static DBManager getDBManager()
{
if (null==dbManager) {
dbManager=new DBManager();
}
return dbManager;
}
}
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
public class DBManager {
private String driver="com.mysql.jdbc.Driver";
private String
url="jdbc:mysql://localhost:3306/hwglxt";
private String username="root";
private String password="admin";
public static Connection connection =null;
private static DBManager dbManager=null;
private DBManager()
{
try
{
Class.forName(driver);
connection=DriverManager.getConnection(url, username, password);
}
catch (Exception e) {
System.out.println("數據庫連接異常");
}
}
public static DBManager getDBManager()
{
if (null==dbManager) {
dbManager=new DBManager();
}
return dbManager;
}
}
catch (Exception e)说有个括号那出错
{
Class.forName(driver);
//connection=DriverManager.getConnection(url, username, password);
}
catch (ClassNotFoundException e) {
System.out.println("數據庫連接異常");
}
try
{
connection=DriverManager.getConnection(url, username, password);
}
catch (SQLException e)
{ System.out.println("SQLException:"+e.getMessage()); }
}
com.dao.impl.ProviderInfoImpl.getAllProviderInfo(ProviderInfoImpl.java:82)
com.servlet.ProviderInfoServlet.doPost(ProviderInfoServlet.java:40)
com.servlet.ProviderInfoServlet.doGet(ProviderInfoServlet.java:19)
javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
note The full stack trace of the root cause is available in the Apache Tomcat/6.0.20 logs.
--------------------------------------------------------------------------------Apache Tomcat/6.0.20
空指针是怎么回事啊
看看你ProviderInfoImpl.java的第82行 哪空了