资料来源: http://sunnylocus.iteye.com/blog/359570
proxool一个数据库连接池框架,提供了对你选择的其它类型的驱动程序的连接池封装。可以非常简单的移植到现存的代码中。完全可配置。快速,成熟,健壮。可以透明地为你现存的JDBC驱动程序增加连接池功能。到目前为止最新版本是proxool 0.9.1,可从官网下载最新版本http://proxool.sourceforge.net
一、配置proxool.xml文件
<?xml version="1.0" encoding="UTF-8"?> <!-- the proxool configuration can be embedded within your own application's. Anything outside the "proxool" tag is ignored. --> <something-else-entirely> <proxool> <alias>dbname</alias> <!--数据源的别名--> <driver-url>jdbc:oracle:thin:@127.0.0.1:1521:testdb</driver-url><!--url连接串--> <driver-class>oracle.jdbc.driver.OracleDriver</driver-class> <!--驱动类--> <driver-properties> <property name="user" value="username" /> <!--用户名--> <property name="password" value="password" /><!--密码--> </driver-properties> <!--最大连接数(默认5个),超过了这个连接数,再有请求时,就排在队列中等候,最大的等待请求数由maximum-new-connections决定 --> <maximum-connection-count>100</maximum-connection-count> <!--最小连接数(默认2个)--> <minimum-connection-count>10</minimum-connection-count> <!--proxool自动侦察各个连接状态的时间间隔(毫秒),侦察到空闲的连接就马上回收,超时的销毁 默认30秒--> <house-keeping-sleep-time>90000</house-keeping-sleep-time> <!--没有空闲连接可以分配而在队列中等候的最大请求数,超过这个请求数的用户连接就不会被接受--> <maximum-new-connections>10</maximum-new-connections> <!--最少保持的空闲连接数(默认2个)--> <prototype-count>5</prototype-count> <!--在使用之前测试--> <test-before-use>true</test-before-use> <!--用于保持连接的测试语句 --> <house-keeping-test-sql>select sysdate from dual</house-keeping-test-sql> </proxool> </something-else-entirely>
二、配置web.xml
<?xml version="1.0" encoding="UTF-8"?> <web-app version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"> <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> <servlet> <servlet-name>Admin</servlet-name> <servlet-class> org.logicalcobwebs.proxool.admin.servlet.AdminServlet </servlet-class> </servlet> <servlet-mapping> <servlet-name>Admin</servlet-name> <url-pattern>/admin</url-pattern> </servlet-mapping> <!-- 配置受保护域,只有Tomcat管理员才能察看连接池的信息 --> <security-constraint> <web-resource-collection> <web-resource-name>proxool</web-resource-name> <url-pattern>/admin</url-pattern> </web-resource-collection> <auth-constraint> <role-name>manager</role-name> </auth-constraint> </security-constraint> <login-config> <auth-method>BASIC</auth-method> <realm-name>proxool manager Application</realm-name> </login-config> <security-role> <description>The role that is required to log in to the Manager Application</description> <role-name>manager</role-name> </security-role> <error-page> <error-code>401</error-code> <location>/401.jsp</location> </error-page> </web-app>
ServletConfigurator:加载并初始化proxool.xml文件,因为它是连接数据库的.其他很多模块都用到数据,所以必须首先加载它
load-on-startup:数值越小,就会先被加载初始化
Admin:监控数据库连接池的连接情况
//获得数据库连接的语句
Connection conn=DriverManager.getConnection("proxool.dbname");
注意:在401.jsp页面中必须加
<%
response.setHeader("WWW-Authenticate", "Basic realm=\"Tomcat Manager Application\"");
%>这句话,否则在访问/admin察看连接池信息时,会直接跳转到401.jsp页面。我们是想让访问admin/的用户必须输入用户名和密码,且必须是manager角色,三次输入不正确才会跳到401.jsp页面,如图
输入正确用户名和密码后才能看到proxool池的信息
http://sunnylocus.iteye.com/upload/picture/pic/34529/d9240b55-37c3-3eac-83c1-cb6aeb6a61aa.jpg
三、更详细的proxool.xml的配置属性说明:
<?xml version="1.0" encoding="ISO-8859-1"?> <!-- Properties for Proxool Configurator testing. Defines the same parameters as TestHelper.buildCompleteAlternativeProperties() --> <something-else-entirely xmlns="http://sumthin.else.entirely" xmlns:proxool="The latest version is available at http://proxool.sourceforge.net/xml-namespace"> <proxool:proxool> <proxool:alias>xml-test-ns</proxool:alias> <proxool:driver-url>jdbc:hsqldb:db/test</proxool:driver-url> <proxool:driver-class>org.hsqldb.jdbcDriver</proxool:driver-class> <proxool:driver-properties> <proxool:property name="user" value="sa"/> <proxool:property name="password" value=""/> </proxool:driver-properties> <proxool:house-keeping-sleep-time>40000</proxool:house-keeping-sleep-time> <proxool:house-keeping-test-sql>select CURRENT_DATE</proxool:house-keeping-test-sql> <proxool:maximum-connection-count>10</proxool:maximum-connection-count> <proxool:minimum-connection-count>3</proxool:minimum-connection-count> <proxool:maximum-connection-lifetime>18000000</proxool:maximum-connection-lifetime> <!-- 5 hours --> <proxool:simultaneous-build-throttle>5</proxool:simultaneous-build-throttle> <proxool:recently-started-threshold>40000</proxool:recently-started-threshold> <proxool:overload-without-refusal-lifetime>50000</proxool:overload-without-refusal-lifetime> <proxool:maximum-active-time>60000</proxool:maximum-active-time> <proxool:verbose>true</proxool:verbose> <proxool:trace>true</proxool:trace> <proxool:fatal-sql-exception>Fatal error</proxool:fatal-sql-exception> <proxool:prototype-count>2</proxool:prototype-count> </proxool:proxool> <nothing-to-do-with-proxool> <proxool:proxool> <proxool:alias>xml-test-ns-2</proxool:alias> <proxool:driver-url>jdbc:hsqldb:db/test</proxool:driver-url> <proxool:driver-class>org.hsqldb.jdbcDriver</proxool:driver-class> <proxool:driver-properties> <proxool:property name="user" value="sa"/> <proxool:property name="password" value=""/> </proxool:driver-properties> <proxool:house-keeping-sleep-time>40000</proxool:house-keeping-sleep-time> <proxool:house-keeping-test-sql>select CURRENT_DATE</proxool:house-keeping-test-sql> <proxool:maximum-connection-count>10</proxool:maximum-connection-count> <proxool:minimum-connection-count>3</proxool:minimum-connection-count> <proxool:maximum-connection-lifetime>18000000</proxool:maximum-connection-lifetime> <!-- 5 hours --> <proxool:simultaneous-build-throttle>5</proxool:simultaneous-build-throttle> <proxool:recently-started-threshold>40000</proxool:recently-started-threshold> <proxool:overload-without-refusal-lifetime>50000</proxool:overload-without-refusal-lifetime> <proxool:maximum-active-time>60000</proxool:maximum-active-time> <proxool:verbose>true</proxool:verbose> <proxool:trace>true</proxool:trace> <proxool:fatal-sql-exception>Fatal error</proxool:fatal-sql-exception> <proxool:prototype-count>2</proxool:prototype-count> </proxool:proxool> </nothing-to-do-with-proxool> </something-else-entirely>
属性列表说明:
fatal-sql-exception: 它是一个逗号分割的信息片段.当一个SQL异常发生时,他的异常信息将与这个信息片段进行比较.如果在片段中存在,那么这个异常将被认为是个致命错误(Fatal SQL Exception ).这种情况下,数据库连接将要被放弃.无论发生什么,这个异常将会被重掷以提供给消费者.用户最好自己配置一个不同的异常来抛出.
fatal-sql-exception-wrapper-class:正如上面所说,你最好配置一个不同的异常来重掷.利用这个属性,用户可以包装SQLException,使他变成另外一个异常.这个异常或者继承SQLException或者继承字RuntimeException.proxool自带了2个实现:'org.logicalcobwebs.proxool.FatalSQLException' 和'org.logicalcobwebs.proxool.FatalRuntimeException' .后者更合适.
house-keeping-sleep-time: house keeper 保留线程处于睡眠状态的最长时间,house keeper 的职责就是检查各个连接的状态,并判断是否需要销毁或者创建.
house-keeping-test-sql: 如果发现了空闲的数据库连接.house keeper 将会用这个语句来测试.这个语句最好非常快的被执行.如果没有定义,测试过程将会被忽略。
injectable-connection-interface: 允许proxool实现被代理的connection对象的方法.
injectable-statement-interface: 允许proxool实现被代理的Statement 对象方法.
injectable-prepared-statement-interface: 允许proxool实现被代理的PreparedStatement 对象方法.
injectable-callable-statement-interface: 允许proxool实现被代理的CallableStatement 对象方法.
jmx: 略
jmx-agent-id: 略
jndi-name: 数据源的名称
maximum-active-time: 如果housekeeper 检测到某个线程的活动时间大于这个数值.它将会杀掉这个线程.所以确认一下你的服务器的带宽.然后定一个合适的值.默认是5分钟.
maximum-connection-count: 最大的数据库连接数.
maximum-connection-lifetime: 一个线程的最大寿命.
minimum-connection-count: 最小的数据库连接数
overload-without-refusal-lifetime: 略
prototype-count: 连接池中可用的连接数量.如果当前的连接池中的连接少于这个数值.新的连接将被建立(假设没有超过最大可用数).例如.我们有3个活动连接2个可用连接,而我们的prototype-count是4,那么数据库连接池将试图建立另外2个连接.这和 minimum-connection-count不同. minimum-connection-count把活动的连接也计算在内.prototype-count 是spare connections 的数量.
recently-started-threshold: 略
simultaneous-build-throttle: 略
statistics: 连接池使用状况统计。 参数“10s,1m,1d”
statistics-log-level: 日志统计跟踪类型。 参数“ERROR”或 “INFO”
test-before-use: 略
test-after-use: 略
trace: 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).你也可以注册一个ConnectionListener (参看ProxoolFacade)得到这些信息.
verbose: 详细信息设置。 参数 bool 值
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1. 在WEB-INF中建立proxool.xml <?xml version="1.0" encoding="UTF-8"?> <proxool> <alias>DBPool</alias> <!--这里是连接池的别名--> <driver-url>jdbc:sqlserver://localhost:1433;DatabaseName=test</driver-url> <driver-class>com.microsoft.sqlserver.jdbc.SQLServerDriver</driver-class> <driver-properties> <property name="user" value="sa"/> <property name="password" value="sa1234"/> </driver-properties> <!-- 自动侦察各个连接状态的时间间隔(毫秒,侦察到空闲的连接就马上回收,超时的销毁 --> <house-keeping-sleep-time>90000</house-keeping-sleep-time> <!-- 最大的等待请求数,即因没有空闲连接可以分配而在队列中等待的最大请求数,超过这个请求数的,用户连接就不会被接受 --> <proxool.simultaneous-build-throttle>20</proxool.simultaneous-build-throttle> <!-- 最少保持的空闲连接数 --> <prototype-count>1</prototype-count> <!-- 允许最在连接数,超过了这个连接,再有请求时,就排在队列中 --> <maximum-connection-count>1</maximum-connection-count> <!-- 最小连接数 --> <minimum-connection-count>1</minimum-connection-count> <!-- 如果发现了空闲的数据库连接.house keeper 将会用这个语句来测试.这个语句最好非常快的被执行.如果没有定义,测试过程将会被忽略。 --> <house-keeping-test-sql>select CURRENT_DATE</house-keeping-test-sql> </proxool> 2. 在web.xml加监听 <!-- proxool 数据连接池 --> <servlet> <servlet-name>proxoolServletConfigurator</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><!--这里对应刚才建立的xml配置文件名--> </init-param> <load-on-startup>1</load-on-startup> </servlet> <!-- proxool提供的管理监控工具,可查看当前数据库连接情况--> <servlet> <servlet-name>Admin</servlet-name> <servlet-class>org.logicalcobwebs.proxool.admin.servlet.AdminServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>Admin</servlet-name> <url-pattern>/admin</url-pattern> </servlet-mapping> 3. jsp测试 <%@ page language="java" import="java.util.*" pageEncoding="GBK"%> <%@page import="java.sql.*"%> <%@page contentType="text/html; charset=GBK"%> <%@page import="test.*"%> <html> <head> <title>ProxoolTest</title> </head> <body bgcolor="#ffffff"> <h1>Proxool连接池测试</h1> <% Connection con = null; Statement stmt = null; ResultSet rs = null; try { con = DriverManager.getConnection("proxool.DBPool"); stmt = con.createStatement(); String query = "select * from test t"; out.println("query:" + query+ "--OK<br/>"); rs = stmt.executeQuery(query); out.println("rs.next():" + rs.next()+ "--OK<br/>"); while (rs.next()) { out.println(rs.getString(3) + "--OK<br/>"); } } catch (SQLException sqle) { out.println("sqle=" + sqle+ "--OK<br/>"); } finally { try { rs.close(); stmt.close(); if (con != null) { con.close(); } } catch (SQLException sqle) { out.println("sqle=" + sqle+ "--OK<br/>"); } } %> </body> </html> 4. main测试 import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.Statement; import org.logicalcobwebs.proxool.configuration.JAXPConfigurator; public class TestProxool { // public static String dburl = // "jdbc:oracle:thin:@192.168.104.192:1521:tim"; public static String dburl = "jdbc:sqlserver://localhost:1433;DatabaseName=test"; public static String user = "sa"; public static String password = "sa1234"; /** * JDBC方式测试 * * @throws Exception */ public static void test1() throws Exception { String testsql = "select * from test"; // 1:注册驱动类 // Class.forName("oracle.jdbc.driver.OracleDriver"); Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver"); // 2:创建数据库连接 Connection conn = DriverManager.getConnection(dburl, user, password); // 3:创建执行SQL的对象 Statement stmt = conn.createStatement(); // 4:执行SQL,并获取返回结果 ResultSet rs = stmt.executeQuery(testsql); // 5:处理返回结果,此处打印查询结果 while (rs.next()) { System.out.print(rs.getString("a") + "\t"); // System.out.print(rs.getString("name") + "\t"); System.out.println(); } // 6:关闭数据库连接 conn.close(); } /** * proxool方式测试 * * @throws Exception */ public static void test2() throws Exception { // Java应用中先要加载配置文件,否则谁知道你配置给谁用的 JAXPConfigurator.configure("D:\\workspace\\PoolTest\\src\\proxool.xml", false); String testsql = "select * from test"; // 1:注册驱动类,这次这个驱动已经不是Oracle的驱动了,是Proxool专用的驱动 Class.forName("org.logicalcobwebs.proxool.ProxoolDriver"); // 2:创建数据库连接,这个参数是一个字符串,是数据源的别名,在配置文件中配置的DBPool,参数格式为:proxool.数据源的别名 Connection conn = DriverManager.getConnection("proxool.DBPool"); // 3:创建执行SQL的对象 Statement stmt = conn.createStatement(); // 4:执行SQL,并获取返回结果 ResultSet rs = stmt.executeQuery(testsql); // 5:处理返回结果,此处打印查询结果 while (rs.next()) { System.out.print(rs.getString("e") + "\t"); // System.out.print(rs.getString("name") + "\t"); System.out.println(); } // 6:关闭数据库连接 conn.close(); } public static void main(String[] args) throws Exception { //test1(); test2(); } } 5. java+jsp (1)java代码 package test; import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import org.logicalcobwebs.proxool.ProxoolException; import org.logicalcobwebs.proxool.ProxoolFacade; import org.logicalcobwebs.proxool.admin.SnapshotIF; import org.logicalcobwebs.proxool.configuration.JAXPConfigurator; public class PoolManager { private static int activeCount = 0; public PoolManager() { } /** * * 获取连接 * getConnection * * * @param name * * @return */ public Connection getConnection() { try { // JAXPConfigurator.configure("D:\\workspace\\PoolTest\\src\\proxool.xml", // false); Class.forName("org.logicalcobwebs.proxool.ProxoolDriver");// proxool驱动类 Connection conn = DriverManager.getConnection("proxool.DBPool"); // 此处的DBPool是在proxool.xml中配置的连接池别名 showSnapshotInfo(); return conn; } catch (Exception ex) { ex.printStackTrace(); } return null; } /** * * 此方法可以得到连接池的信息 * showSnapshotInfo */ private void showSnapshotInfo() { try { SnapshotIF snapshot = ProxoolFacade.getSnapshot("DBPool", true); int curActiveCount = snapshot.getActiveConnectionCount();// 获得活动连接数 int availableCount = snapshot.getAvailableConnectionCount();// 获得可得到的连接数 int maxCount = snapshot.getMaximumConnectionCount();// 获得总连接数 if (curActiveCount != activeCount)// 当活动连接数变化时输出的信息 { System.out.println("活动连接数:" + curActiveCount + "(active) 可得到的连接数:" + availableCount + "(available) 总连接数:" + maxCount + "(max)"); activeCount = curActiveCount; } } catch (ProxoolException e) { e.printStackTrace(); } } /** * * 获取连接 * * getConnection * * * @param name * * @return */ public Connection getConnection(String name) { return getConnection(); } /** * * 释放连接 * freeConnection * * * @param conn * */ public void freeConnection(Connection conn) { if (conn != null) { try { conn.close(); } catch (SQLException e) { e.printStackTrace(); } } } /** * * 释放连接 * freeConnection * * * @param name * * * @param con * */ public void freeConnection(String name, Connection con) { freeConnection(con); } public void getQuery() { try { Connection conn = getConnection(); if (conn != null) { Statement statement = conn.createStatement(); ResultSet rs = statement.executeQuery("select * from test"); int c = rs.getMetaData().getColumnCount(); while (rs.next()) { System.out.println(); for (int i = 1; i <= c; i++) { System.out.print(rs.getObject(i)); } } rs.close(); } freeConnection(conn); } catch (SQLException e) { e.printStackTrace(); } } } (2)jsp代码 <%@ page language="java" import="java.util.*" pageEncoding="GBK"%> <%@page import="java.sql.*"%> <%@page contentType="text/html; charset=GBK"%> <%@page import="test.*"%> <html> <head> <title>ProxoolTest</title> </head> <body bgcolor="#ffffff"> <h1> Proxool连接池测试 </h1> <% Connection con = null; try { PoolManager poo = new PoolManager(); //con =poo.getConnection(); poo.getQuery(); } catch (Exception sqle) { out.println("sqle=" + sqle + "--OK<br/>"); } finally { } %> </body> </html>