package fengyun.Fastmail.servlets;

import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.util.*;
    /**
     * 定時清除垃圾附件
     * @author fengyun
     * @version 1.00
     */
public class RubbishAttachmentCleaner extends HttpServlet implements Runnable {
	private static String AttachmentTempPath = null;								//附件臨時路徑
	private static final long SleepTime = 3600000;									//休眠時間間隔
	private static Thread Cleaner = null;											//清除文件的時間線程
	/**
	 * 初始化Servlet
	 * @param config 設置信息
	 */
	public void init(ServletConfig config) throws ServletException
	{
		super.init(config);
		AttachmentTempPath = config.getInitParameter("AttachmentTempPath");
		Cleaner = new Thread(this);
		Cleaner.start();
	}
	/**
	 * 清除附件的運行函數
	 */
	public void run() {
		File file = new File(this.AttachmentTempPath);
		if (!file.exists() || file.isFile()) return ;
		while(true) {
			String[] tmpFileList = file.list(new AttachmentFilenameFilter(this.SleepTime));
			for(int i = 0; i < tmpFileList.length ; i++) {
				File tmpFile = new File(this.AttachmentTempPath + File.separator + tmpFileList[i]);
				if (tmpFile.exists() && tmpFile.isFile()) tmpFile.delete();
			}
			try {
				Cleaner.sleep(SleepTime);
			}
			catch(Exception e) {
				e.printStackTrace();
			}
		}
	}
	/**
	 * 選取過期附件的過濾器
	 */
	private static class AttachmentFilenameFilter implements FilenameFilter {
		private long StayTime = 1200000;
		/**
		 * 構造過濾器
		 * @param staytime 選取的時間間隔
		 */
		public AttachmentFilenameFilter(long staytime) {
			this.StayTime = staytime;
		}		public boolean accept(File dir,String filename) {			File file=new File(dir.getAbsolutePath() + File.separator + filename);			if (file.isDirectory()) return false;						int cur = filename.indexOf(";");			if (cur < 0 || cur >= filename.length())	return false;
			long createtime = System.currentTimeMillis();
			long thistime   = createtime;			try {
				createtime = Long.valueOf(filename.substring(0,cur)).longValue();			}			catch(Exception e) {				createtime = thistime;
				e.printStackTrace();			}
			if (createtime < (thistime - this.StayTime)) return true;			else return false;			
		}
	}
}