java项目启动时执行指定方法

想到的就是监听步骤如下：

1.配置web.xml

 <listener>  
    <listener-class>com.listener.InitListener</listener-class>  
</listener> 

2.编写InitListener类

package com.listener;

import java.io.File;

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

import com.seegot.util.PropertyUtil;

public class InitListener implements ServletContextListener {

    @Override
    public void contextDestroyed(ServletContextEvent arg0) {
        // TODO Auto-generated method stub

    }

    @Override
    public void contextInitialized(ServletContextEvent arg0) {
        // TODO Auto-generated method stub
        System.out.println("================>[ServletContextListener]自动加载启动开始."); 
        String resourceFilesPath = PropertyUtil.getProperty("tempZipPath");
        clearFiles(resourceFilesPath);
    }
    // 删除文件和目录
    private static boolean clearFiles(String workspaceRootPath) {
        File file = new File(workspaceRootPath);
        if (file.exists()) {
            deleteFile(file);
        }
        // resources 文件夹被删除后需新建
        if (!file.exists() && workspaceRootPath.endsWith("resources")) {
            return file.mkdir();
        } else if (!file.exists()) {
            return true;
        }
            return false;
        }

    private static boolean deleteFile(File file) {
        if (file.isDirectory()) {
            File[] files = file.listFiles();
            for (int i = 0; i < files.length; i++) {
                deleteFile(files[i]);
            }
        }
            return file.delete();
    } 
}