问题描述

Java web jdbc怎么连接数据库，要配置什么啊

代码都已经打完了，但是一直连接不成功，sqlserver数据库驱动也下下来了并放到buding path里了，sqlserver协议tcp/ip也更改了，数据库也用用户名密码登陆了，还差什么啊，求大神指教，下面是代码，都是网上的，应该没错。

package com.demo;

import java.io.*;
import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import javax.servlet.*;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.*;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**

• Servlet implementation class register
  */
  @WebServlet("/register.do")
  public class register extends HttpServlet {
  public Connection cn;
  public PreparedStatement ps;
  public ResultSet rs;
  //连接数据库
  public void getCn()
  {
  String url="jdbc:microsoft:sqlserver://192.168.1.119:1433;DatabaseName=Web";
  String driverpath="com.microsoft.jdbc.sqlserver.SQLServerDriver";
  String name="sa";
  String pwd="123456";
  try{
  Class.forName(driverpath);
  cn=DriverManager.getConnection(url,name,pwd);
  if(cn!=null)
  {
  System.out.println("ok");
  cn.close();
  }
  else
  System.out.println("数据库连接失败！");
  }catch(Exception e)
  {
  e.printStackTrace();
  }
  }
  protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
  // TODO Auto-generated method stub
  response.getWriter().append("Served at: ").append(request.getContextPath());
  }

  /**

  • @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
    */
    //得到post资源
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    response.setContentType("text/html;charset=gbk");
    PrintWriter out=response.getWriter();
    String name=request.getParameter("username");
    String pwd=request.getParameter("password");
    System.out.println(name);
    System.out.println(pwd);
    if(this.insert(name,pwd)==true)
    {
    out.println("注册成功");
    }
    else
    out.println("注册失败");

    out.flush();
    out.close();
    }
    //注册添加数据
    public boolean insert(String name,String pwd)
    {
    getCn();
    boolean b=false;
    String sql="insert into login values(?,?)";
    try{
    ps=cn.prepareStatement(sql);
    ps.setString(1, name);
    ps.setString(2, pwd);
    ps.execute();
    b=true;
    }catch(Exception e)
    {
    e.printStackTrace();
    }finally {
    try{
    if(rs!=null)
    rs.close();
    else if(ps!=null)
    ps.close();
    else if(cn!=null)
    cn.close();
    }catch(Exception e){}
    }
    return b;
    }

}

解决方案

是显示数据库连接失败还是抛异常了

解决方案二：

Java Web数据库配置

解决方案三：

try{
Class.forName(driverpath);
cn=DriverManager.getConnection(url,name,pwd);
if(cn!=null)
{
System.out.println("ok");
cn.close();
}

你拿到cn然后直接给它关闭了。。怎么调用cn.preparestatement()方法。。