问题描述
- memory leak我的 jdbc 被强制注销
- memory leak我的 jdbc 被强制注销 我前几天还好好的，今天发现能够连到数据库oracle，但是新的程序无法在数据库中呈现出来，并且原来的表也没有了
The web application [UsersManager2] registered the JDBC driver [oracle.jdbc.driver.OracleDriver] but failed to unregister it when the web application was stopped. To prevent a memory leak the JDBC Driver has been forcibly unregistered.
这个是我的登录Servlet
package com.wzy.view;
import java.io.IOException;
import java.io.PrintWriter;import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;public class LoginServlet extends HttpServlet {
public void doGet(HttpServletRequest request HttpServletResponse response) throws ServletException IOException { response.setContentType(""text/html;charset=utf-8""); //response.setCharacterEncoding(""utf-8""); PrintWriter out = response.getWriter(); //返回一个界面(html技术) out.println(""<img src='imgs/1.png'/><hr/>""); out.println(""<h1>用户登录</h1>""); //action 应该这样写/web应用名/Servlet的url out.println(""<form action='/UsersManager2/LoginCLServlet ' method='post'>""); out.println(""用户名:<input type='text' name='id'/><br/>""); out.println(""密码:<input type='password' name='password'/><br/>""); out.println(""<input type='submit' value='登录'/><br/>""); out.println(""</form>""); String errInfo=(String) request.getAttribute(""err""); if(errInfo!=null){ out.println(""<font color='red'>""+errInfo+""</font>""); } out.println(""<hr/><img src='imgs/2.png'/>"");}** 这是登录处理转向Servlet**
package com.wzy.controller;import java.io.IOException;
import java.io.PrintWriter;
import java.sql.*;import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;public class LoginCLServlet extends HttpServlet {
public void doGet(HttpServletRequest request HttpServletResponse response) throws ServletException IOException { //向浏览器返回中文 request.setCharacterEncoding(""utf-8""); //向控制台返回中文 在这里没什么用 //response.setContentType(""text/html;charset=utf-8""); //PrintWriter out = response.getWriter(); //接收用户提交的用户名和密码 String id=request.getParameter(""id""); String password=request.getParameter(""password""); //到数据库中取验证 Connection ct = null; ResultSet rs= null; PreparedStatement ps=null; try { //1.加载驱动 Class.forName(""oracle.jdbc.driver.OracleDriver""); //2.得到连接 ct=DriverManager.getConnection(""jdbc:oracle:thin:@127.0.0.1:1521:ORACLE""c##scott""tiger""); //3.创建PreparedStatement ps=ct.prepareStatement(""select * from users where id=? and passwd=?""); //给?赋值 ps.setObject(1id); ps.setObject(2 password); //4.执行操作 rs=ps.executeQuery(); //5.根据结果做处理 if(rs.next()){ //说明该用户合法 request.getRequestDispatcher(""/MainFrame"").forward(requestresponse); }else{ request.setAttribute(""err""用户id或者 密码有误!""); request.getRequestDispatcher(""/LoginServlet"").forward(requestresponse); } }catch (Exception e){ request.setAttribute(""err""您的输入id不是数字!""); request.getRequestDispatcher(""/LoginServlet"").forward(requestresponse); e.printStackTrace(); } finally{ //关闭资源 if(rs!=null){ try { rs.close(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } rs=null; } if(ps!=null ){ try { ps.close(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } ps=null; } if(ct!=null){ try { ct.close(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } ct=null; } }这是调转后第一个统筹页面****
package com.wzy.view;import java.io.IOException;
import java.io.PrintWriter;import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;public class MainFrame extends HttpServlet {
public void doGet(HttpServletRequest request HttpServletResponse response) throws ServletException IOException { response.setContentType(""text/html;charset=utf-8""); PrintWriter out = response.getWriter(); out.println(""<img src='imgs/1.png'/>测试登录servlet页面</a> <a href='/UsersManager2/LoginServlet'>返回重新登录</a><hr/>""); //out.println(""<h1>测试登录</h1>""); out.println(""<h3>请选择您要进行的操作</h3>""); out.println(""<a href='/UsersManager2/ManageUsers'>管理用户</a><br/>""); out.println(""<a herf=''>添加用户</a><br/>""); out.println(""<a herf=''>查找用户</a><br/>""); out.println(""<a herf=''>退出系统</a><br/>""); out.println(""<hr/><img src='imgs/2.png'/>"");}接下来点进去会看到一张绿色的表10条信息我之前一直好好的****
这个是我用jdbc连接oracle 看表的地方现在被强制注销，
我明明打了finally 然后close了，可是 却说我的项目在web application停止后没有被释放，所以为了防止内存泄露要强行关闭jdbc驱动，导致我现在
无法用jdbc 来更新内容，想问一下究竟是怎么回事 还望高手指点
下面的程序只能显示到“管理用户”这一行
最下面的数字也能打印但是 jdbc的链接这里被停止了，我现在不明白的是导致我连不上的原因是哪里没被释放，还是要再注册一下呢?
package com.wzy.view;import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;public class ManageUsers extends HttpServlet {
public void doGet(HttpServletRequest request HttpServletResponse response) throws ServletException IOException { response.setContentType(""text/html;charset=utf-8""); PrintWriter out = response.getWriter(); out.println(""<img src='imgs/1.png'/>测试登录servlet页面</a> <a href='/UsersManager2/LoginServlet'>返回主界面</a> <a href='/UsersManager2/LoginServlet'>安全退出</a><hr/>""); out.println(""<h1>管理用户</h1>""); //从数据库中取出用户信息，并显示 //到数据库中去验证 Connection ct=null; ResultSet rs=null; PreparedStatement ps=null; try{ //1.加载驱动 Class.forName(""oracle.jdbc.driver.OracleDriver""); //2.得到连接 ct=DriverManager.getConnection(""jdbc:oracle:thin:@127.0.0.1:1521:ORACLE""c##scott""tiger""); //算出共有多少页 rs=ps.executeQuery(); //1.查询rowCount rs.next(); //把游标下移 //4.执行操作 rs=ps.executeQuery(); out.println(""<table border=1px bordercolor=green cellspacing=0 width=500px>""); out.println(""<tr><th>id</th><th>用户名</th><th>email</th><th>级别</th></tr>""); //循环显示所有用户信息 while(rs.next()){ out.println(""<tr><td>""+rs.getInt(1)+</td><td>""+rs.getString(2)+</td><td>""+rs.getString(3)+</td><td>""+rs.getInt(4)+</td></tr>""); } out.println(""</table>""); //显示分页 }catch(Exception e){ }finally{ //关闭资源 if(rs!=null){ try{ rs.close(); }catch(SQLException e){ e.printStackTrace(); } } rs=null; } if(ps!=null){ try{ ps.close(); }catch (SQLException e){ e.printStackTrace(); } ps=null; } if(ct!=null){ try{ ct.close(); }catch(SQLException e){ e.printStackTrace(); } ct=null; } out.println(""1324234""); }望大神指教，网上有用dbcp 重新写个close和改变 dbcp的配置来解决的，可我是新手还不懂hibernate
也有到server.xml里去关掉memory leak的监听，我试了不行，我现在的情况是能够连到数据库oracle，但是原先的表无法显示和新写的代码无法传递进去，发生了宕机。还望各路高手救命