proxool的使用总结
在项目中使用proxool做数据源管理，这里记录下配置代码与需要注意的事项。
添加jar包：proxool-0.9.0RC3.jar 在WEB-INF下，创建proxool.xml文件，代码如下：
<?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>数据源名</alias>
<driver-url>jdbc:mysql://localhost:3306/数据库名</driver-url>
<driver-class>com.mysql.jdbc.Driver</driver-class>
<driver-properties>
<property name="user" value="用户名"/>
<property name="password" value="密码"/>
<property name="useUnicode" value="true"/>
<property name="characterEncoding" value="UTF-8"/>
</driver-properties>
<house-keeping-sleep-time>40000</house-keeping-sleep-time>
<maximum-connection-count>250</maximum-connection-count>
<minimum-connection-count>3</minimum-connection-count>
<maximum-connection-lifetime>3000000</maximum-connection-lifetime> <!-- 5 hours -->
<simultaneous-build-throttle>5</simultaneous-build-throttle>
<recently-started-threshold>400000</recently-started-threshold>
<overload-without-refusal-lifetime>500000</overload-without-refusal-lifetime>
<maximum-active-time>600000</maximum-active-time>
<verbose>true</verbose>
<trace>true</trace>
<house-keeping-test-sql>select CURRENT_DATE</house-keeping-test-sql>
<fatal-sql-exception>Fatal error</fatal-sql-exception>
<prototype-count>2</prototype-count>
<statistics-log-level>INFO</statistics-log-level>
</proxool>
</something-else-entirely>
注：proxool.xml的配置参数详细说明请参考这里。
然后在web.xml文件中进行配置，添加如下代码：
<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> -->
上述代码中被注释掉的部分在开发过程中可以释放，如果释放，则会开启数据源监控页面，如果您的访问地址为www.xxx.com，那么数据源监控URL为：www.xxx.com/admin。网站发布到服务器上后，建议关闭该功能。
注意：如果工程中存在监听器，而监听器中调用了数据库中的数据，那么在系统启动的时候会报错
java.sql.SQLException: org.logicalcobwebs.proxool.ProxoolException: Attempt to refer to a unregistered pool by its alias ‘别名’
或者
java.sql.SQLException: No suitable driver found for '数据源名'
这时的解决方案为：把proxool交给监听器进行处理：
新建类：
import java.io.File;
import java.util.Enumeration;
import java.util.Properties;
import javax.servlet.ServletContext;
import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.logicalcobwebs.proxool.ProxoolException;
import org.logicalcobwebs.proxool.configuration.JAXPConfigurator;
import org.logicalcobwebs.proxool.configuration.PropertyConfigurator;
/**
* @author wangtao
*/
public class ProxoolListener implements ServletContextListener {
private static final Log LOG = LogFactory.getLog(ProxoolListener.class);
private static final String XML_FILE_PROPERTY = "xmlFile";
private static final String PROPERTY_FILE_PROPERTY = "propertyFile";
private static final String AUTO_SHUTDOWN_PROPERTY = "autoShutdown";
@SuppressWarnings("unused")
private boolean autoShutdown = true;
public void contextDestroyed(ServletContextEvent arg0) {
System.out.println("destroy database pool....");
}
@SuppressWarnings("unchecked")
public void contextInitialized(ServletContextEvent contextEvent) {
System.out.println("init................");
ServletContext context = contextEvent.getServletContext(); // 对应servlet的init方法中ServletConfig.getServletContext()
String appDir = contextEvent.getServletContext().getRealPath("/");
Properties properties = new Properties();
Enumeration names = context.getInitParameterNames();
while (names.hasMoreElements()) {
String name = (String) names.nextElement();
String value = context.getInitParameter(name);
if (name.equals(XML_FILE_PROPERTY)) {
try {
File file = new File(value);
if (file.isAbsolute()) {
JAXPConfigurator.configure(value, false);
} else {
JAXPConfigurator.configure(appDir + File.separator + value, false);
}
} catch (ProxoolException e) {
LOG.error("Problem configuring " + value, e);
}
} else if (name.equals(PROPERTY_FILE_PROPERTY)) {
try {
File file = new File(value);
if (file.isAbsolute()) {
PropertyConfigurator.configure(value);
} else {
PropertyConfigurator.configure(appDir + File.separator + value);
}
} catch (ProxoolException e) {
LOG.error("Problem configuring " + value, e);
}
} else if (name.equals(AUTO_SHUTDOWN_PROPERTY)) {
autoShutdown = Boolean.valueOf(value).booleanValue();
} else if (name.startsWith("jdbc")) { // 此处以前是PropertyConfigurator.PREFIX改为jdbc,因为此源码是0.9.1版本的,与0.9RC3版本有点不一样
properties.setProperty(name, value);
}
}
if (properties.size() > 0) {
try {
PropertyConfigurator.configure(properties);
} catch (ProxoolException e) {
LOG.error("Problem configuring using init properties", e);
}
}
}
}
然后web.xml中的配置如下：
<context-param> <param-name>xmlFile</param-name> <param-value>WEB-INF/proxool.xml</param-value> </context-param>
获取数据源连接代码：
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
public class DBConnectionManager {
private static Connection conn;
public static Connection getConnection()
{
try
{
conn = DriverManager.getConnection("proxool.数据源名");
if (conn == null)
{
throw new SQLException("数据库无值");
}
}
catch (Exception ex)
{
System.out.println(ex.getMessage());
ex.printStackTrace();
}
return conn;
}
}
参考资料：http://cbf0713.blog.163.com/blog/static/907789052010510105453412/
