java 数据库连接池 proxool Java数据库连接池之proxool_动力节点Java学院整理
人气:0想了解Java数据库连接池之proxool_动力节点Java学院整理的相关内容吗,在本文为您仔细讲解java 数据库连接池 proxool的相关知识和一些Code实例,欢迎阅读和指正,我们先划重点:java,数据库连接池,java,proxool,下面大家一起来学习吧。
Proxool是一种Java数据库连接池技术。sourceforge下的一个开源项目,这个项目提供一个健壮、易用的连接池,最为关键的是这个连接池提供监控的功能,方便易用,便于发现连接泄漏的情况。
目前是和DBCP以及C3P0一起,最为常见的三种JDBC连接池技术。
日前,Hibernate官方宣布由于Bug太多不再支持DBCP,而推荐使用 Proxool或C3P0。
下面通过一个Demo说明一下如何使用:
项目结构如下:
DBLink.Java文件中的代码:
package com.bjpowernode.util; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.ResultSetMetaData; import java.sql.SQLException; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; public class DBLink { private Connection connection; private PreparedStatement preparedStatement; private ResultSet resultSet; static{ try { Class.forName("org.logicalcobwebs.proxool.ProxoolDriver"); //加载驱动 }catch (ClassNotFoundException e) { System.out.println("加载驱动失败!"); e.printStackTrace(); } } private Connection getConn(){ try { if(connection==null||connection.isClosed()){ connection = DriverManager.getConnection("proxool.mysqlsource"); //获取连接 } } catch (SQLException e) { System.out.println("获取连接失败!"); e.printStackTrace(); } return connection; } public List<Map<String, Object>> select(String sql, Object [] params){ List<Map<String, Object>> list = new ArrayList<Map<String, Object>>(); try{ connection = this.getConn(); preparedStatement = connection.prepareStatement(sql); if(params != null){ for(int i =0; i<params.length; i++){ preparedStatement.setObject(i+1, params[i]);//逐一给问号赋值 } } resultSet = preparedStatement.executeQuery(); ResultSetMetaData rsmd = resultSet.getMetaData(); int columnCount = rsmd.getColumnCount(); while(resultSet.next()){ Map<String, Object> map = new HashMap<String, Object>(); for(int i =1; i<=columnCount;i++){ String columnName = rsmd.getColumnName(i); Object obj = null; if(rsmd.getColumnTypeName(i).equals("DATE")){ obj = resultSet.getString(columnName); }else{ obj = resultSet.getObject(columnName); } map.put(columnName, obj); } list.add(map); } }catch(SQLException e){ e.printStackTrace(); }finally{ close(); } return list; } private void close(){ try { if(resultSet != null){ resultSet.close(); } } catch (SQLException e) { e.printStackTrace(); } try { if(preparedStatement != null){ preparedStatement.close(); } } catch (SQLException e) { e.printStackTrace(); } try { connection.close(); } catch (SQLException e) { e.printStackTrace(); } } }
proxool.xml文件中的代码:
<?xml version="1.0" encoding="UTF-8"?> <proxool-config> <proxool> <alias>mysqlsource</alias> <driver-url>jdbc:mysql://localhost:3306/test</driver-url> <driver-class>com.mysql.jdbc.Driver</driver-class> <driver-properties> <property name="user" value="root" /> <property name="password" value="root" /> </driver-properties> <!-- 保留线程处于睡眠状态的最长时间 --> <house-keeping-sleep-time>60000</house-keeping-sleep-time> <maximum-connection-count>30</maximum-connection-count> <minimum-connection-count>10</minimum-connection-count> <!-- 连接池中可用的连接数量(空闲状态) --> <prototype-count>5</prototype-count> <maximum-new-connections>1</maximum-new-connections> <simultaneous-build-throttle>1</simultaneous-build-throttle> <!-- 连接池使用状态 --> <statistics>30s,10m,1d</statistics> <!-- 连接池日志类型 --> <statistics-log-level>ERROR</statistics-log-level> <!-- 如果为true,那么每个被执行的SQL语句将会在执行期被log记录(DEBUG LEVEL) --> <trace>true</trace> <house-keeping-test-sql>select CURRENT_DATE</house-keeping-test-sql> </proxool> </proxool-config>
web.xml文件中的代码:
<?xml version="1.0" encoding="UTF-8"?> <web-app version="3.0" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"> <!-- 连接池 --> <servlet> <servlet-name>ServletConfigurator</servlet-name> <servlet-class>org.logicalcobwebs.proxool.configuration.ServletConfigurator</servlet-class> <init-param> <param-name>xmlFile</param-name> <param-value>WEB-INF/proxool.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <welcome-file-list> <welcome-file>index.jsp</welcome-file> </welcome-file-list> </web-app>
index.jsp文件中的代码:
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <%@page import="com.bjpowernode.util.DBLink,java.util.List,java.util.Map"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>首页</title> </head> <body> <table width="100%" border="1px"> <tr> <th>序号 </th><th>班级名称</th><th>开班日期</th><th>结束日期</th><th>状态</th><th>操作</th> </tr> <% String sql = "SELECT id, class_name, begin_date, end_date, state FROM class "; DBLink db = new DBLink(); List<Map<String, Object>> list = db.select(sql, null); int index = 0; for (Map<String, Object> map : list) { index = index + 1; int id = Integer.parseInt(map.get("id").toString()); String className = map.get("class_name").toString(); String beginDate = map.get("begin_date").toString(); String endDate = map.get("end_date").toString(); int state = Integer.parseInt(map.get("state").toString()); String stateName = (state == 0 ? "未启用" : "启用"); %> <tr align="center"> <td><%=index%></td><td><%=className%></td><td><%=beginDate%></td><td><%=endDate%></td><td><%=stateName%></td><td>【<a href="###" rel="external nofollow" rel="external nofollow" rel="external nofollow" onclick="">修改</a>】【<a href="###" rel="external nofollow" rel="external nofollow" rel="external nofollow" onclick="">查看</a>】【<a href="###" rel="external nofollow" rel="external nofollow" rel="external nofollow" onclick="">删除</a>】</td> </tr> <% } %> </table> </body> </html>
总结
以上所述是小编给大家介绍的Java数据库连接池之proxool,希望对大家有所帮助,如果大家有任何疑问请给我留言,小编会及时回复大家的。在此也非常感谢大家对网站的支持!
加载全部内容