在tomcat中启动的文件-ServletContextListener实现全局配置装载入内存

1 tomcat加载的类

package com.jysoft.memcump.common;

import java.io.IOException;
import java.util.Properties;

import javax.servlet.ServletContext;
import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;

public class InitDbMessage implements ServletContextListener{

public static Properties props = new Properties();

@Override
public void contextDestroyed(ServletContextEvent arg0) {
}

@Override
public void contextInitialized(ServletContextEvent servletContextEvent) {

try {
props.load(InitDbMessage.class.getResourceAsStream("db.properties"));
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
ServletContext servletContext = servletContextEvent.getServletContext();
servletContext.setAttribute("driver", props.getProperty("driver"));
servletContext.setAttribute("url", props.getProperty("url"));
servletContext.setAttribute("username", props.getProperty("username"));
servletContext.setAttribute("password", props.getProperty("password"));
}
}

2 使用servlet中进行获取或jsp（这个没测试）中
ServletContext context = this.getServletContext();
System.out.println(context.getAttribute("driver"));

3 经过试验，可以获取测试结果