文件监视器

1.在web.xml配置文件监视器。

  <listener>
     <listener-class>com.wgj.filter.FileModifyListener
     </listener-class>
  </listener>

2.监视器实现FileModifyListener.java

package com.wgj.filter;

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

import org.apache.log4j.Logger;

public class FileModifyListener implements ServletContextListener {

	FileThread fileThread;
	Logger log = Logger.getLogger(FileModifyListener.class);
	public FileModifyListener() {
	}
	@Override
	public void contextDestroyed(ServletContextEvent sce) {
	}

	@Override
	public void contextInitialized(ServletContextEvent sce) {
		fileThread = new FileThread();
		fileThread.setDaemon(true);//作为后台线程运行
		log.debug("File Listener Initialized: OK" );
		try {
//			System.out.println("File Listener Initialized: OK");
			fileThread.start();
		} catch(Exception e) {
			log.debug("File Listener contextInitialized:",e);
		}
	}

}

3.线程实现类FileThread.java

package com.wgj.home;

import java.io.File;

import javax.servlet.ServletContext;

public class FileThread extends Thread {
	private File fileDir = null;
	private String monitorPath = null;
	private String storePath = null;
	FileMonitor monitorFileDir =null;
	FileMonitor monitorFile =null;
	
	public FileThread() {
		monitorPath = "c:\\";
		storePath =  "e:\";
		FileMonitor monitorFileDir = new FileMonitor(1000);
		FileMonitor monitorFile = new FileMonitor(1000);
		fileDir = new File(monitorPath);
		monitorFileDir.addFile(fileDir);
		monitorFileDir.addListener(new MonitorFileDirChanger(monitorFile, fileDir));
		File[] files = fileDir.listFiles();
		for (int i = 0; i < files.length; i++) {
			monitorFile.addFile(files[i]);
			monitorFile.addListener(new MonitorFileChanger());
		}
	}

	public void run() {
		while (!false)
		{
			try {
				Thread.sleep(2000);
			} catch (InterruptedException e) {
				e.printStackTrace();
			}
			
		}
	}
	
	private class MonitorFileChanger implements FileListener {
		public void fileChanged(File file) {
			FileOperator fileCopy = new FileOperator();
			fileCopy.copyFile(monitorPath + "\\" + file.getName(), storePath + file.getName());
		}
	}

	private class MonitorFileDirChanger implements FileListener {
		FileMonitor monitorFile;
		File fileDir;

		public MonitorFileDirChanger(FileMonitor monitorFile, File fileDir) {
			this.monitorFile = monitorFile;
			this.fileDir = fileDir;
		}

		public void fileChanged(File file) {
			monitorFile.removeAllListener();
			File[] files = fileDir.listFiles();
			for (int i = 0; i < files.length; i++) {
				monitorFile.addFile(files[i]);
				monitorFile.addListener(new MonitorFileChanger());
			}
			FileOperator fileCopy = new FileOperator();
			fileCopy.copyFolder(monitorPath, storePath);
		}
	}
}

4.其他工具类
4.1 FileListener.java

package com.wgj.home;

import java.io.File;

/**
 * Interface for listening to disk file changes.
 * @see FileMonitor
 * 
 * @author <a href="mailto:[e-mail]">Jacob Dreyer</a>
 */   
public interface FileListener
{
  /**
   * Called when one of the monitored files are created, deleted
   * or modified.
   * 
   * @param file  File which has been changed.
   */
  void fileChanged (File file);
}

4.2 FileMonitor.java

package com.wgj.home;

import java.util.*;
import java.io.File;
import java.lang.ref.Reference;//WeakReference;



/**
 * Class for monitoring changes in disk files.
 * Usage:
 *
 *    1. Implement the FileListener interface.
 *    2. Create a FileMonitor instance.
 *    3. Add the file(s)/directory(ies) to listen for.
 *
 * fileChanged() will be called when a monitored file is created,
 * deleted or its modified time changes.
 *
 * @author <a href="mailto:[e-mail]">Jacob Dreyer</a>
 */   
public class FileMonitor
{
  private Timer       timer_;
  private HashMap     files_;       // File -> Long
  private Collection  listeners_;   // of WeakReference(FileListener)
   

  /**
   * Create a file monitor instance with specified polling interval.
   * 
   * @param pollingInterval  Polling interval in milli seconds.
   */
  public FileMonitor (long pollingInterval)
  {
    files_     = new HashMap();
    listeners_ = new ArrayList();

    timer_ = new Timer (true);
    timer_.schedule (new FileMonitorNotifier(), 0, pollingInterval);
  }


  
  /**
   * Stop the file monitor polling.
   */
  public void stop()
  {
    timer_.cancel();
  }
  

  /**
   * Add file to listen for. File may be any java.io.File (including a
   * directory) and may well be a non-existing file in the case where the
   * creating of the file is to be trepped.
   * <p>
   * More than one file can be listened for. When the specified file is
   * created, modified or deleted, listeners are notified.
   * 
   * @param file  File to listen for.
   */
  public void addFile (File file)
  {
    if (!files_.containsKey (file)) {
      long modifiedTime = file.exists() ? file.lastModified() : -1;
      files_.put (file, new Long (modifiedTime));
    }
  }

  

  /**
   * Remove specified file for listening.
   * 
   * @param file  File to remove.
   */
  public void removeFile (File file)
  {
    files_.remove (file);
  }


  
  /**
   * Add listener to this file monitor.
   * 
   * @param fileListener  Listener to add.
   */
  public void addListener (FileListener fileListener)
  {
    // Don't add if its already there
    for (Iterator i = listeners_.iterator(); i.hasNext(); ) {
     // Reference reference = (Reference) i.next();
      
      FileListener listener = (FileListener)  i.next();//reference.get();
      if (listener == fileListener)
        return;
    }

    // Use WeakReference to avoid memory leak if this becomes the
    // sole reference to the object.
    listeners_.add (fileListener);//new Reference (
  }


  
  /**
   * Remove listener from this file monitor.
   * 
   * @param fileListener  Listener to remove.
   */
  public void removeListener (FileListener fileListener)
  {
    for (Iterator i = listeners_.iterator(); i.hasNext(); ) {
    // Reference reference = (Reference) i.next();
      FileListener listener = (FileListener)  i.next();//reference.get();
      if (listener == fileListener) {
        i.remove();
        break;
      }
    }
  }
  
  /**
   * Remove listener from this file monitor.
   * 
   * @param fileListener  Listener to remove.
   */
  public void removeAllListener ()
  {
    for (Iterator i = listeners_.iterator(); i.hasNext(); ) {
    // Reference reference = (Reference) i.next();
      FileListener listener = (FileListener)  i.next();//reference.get();
      i.remove();
    }
  }


  
  /**
   * This is the timer thread which is executed every n milliseconds
   * according to the setting of the file monitor. It investigates the
   * file in question and notify listeners if changed.
   */
  private class FileMonitorNotifier extends TimerTask
  {
    public void run()
    {
      // Loop over the registered files and see which have changed.
      // Use a copy of the list in case listener wants to alter the
      // list within its fileChanged method.
      Collection files = new ArrayList (files_.keySet());
      
      for (Iterator i = files.iterator(); i.hasNext(); ) {
        File file = (File) i.next();
        long lastModifiedTime = ((Long) files_.get (file)).longValue();
        long newModifiedTime  = file.exists() ? file.lastModified() : -1;

        // Chek if file has changed
        if (newModifiedTime != lastModifiedTime) {

          // Register new modified time
          files_.put (file, new Long (newModifiedTime));

          // Notify listeners
          for (Iterator j = listeners_.iterator(); j.hasNext(); ) {
            //Reference reference = (Reference) j.next();
            FileListener listener = (FileListener) j.next();

            // Remove from list if the back-end object has been GC'd
            if (listener == null)
              j.remove();
            else
              listener.fileChanged (file);
          }
        }
      }
    }
  }


  /**
   * Test this class.
   * 
   * @param args  Not used.
   */
  public static void main (String args[])
  {
    // Create the monitor
    FileMonitor monitor = new FileMonitor (1000);
    // Add some files to listen for
    monitor.addFile (new File ("E:\\deploy\\test"));    
    monitor.addFile (new File ("E:\\deploy\\test\\1.txt")); 
    // Add a dummy listener
    monitor.addListener (monitor.new TestListener());
    // Avoid program exit
    while (!false) 
    {
    	
    	try {
			Thread.sleep(20);
		} catch (InterruptedException e) {
			e.printStackTrace();
		}
    }
  }

  
  private class TestListener implements FileListener {
	  public void fileChanged (File file) {
		  System.out.println ("File changed: " + file);
	  }
  }
}

4.3 FileOperator.java

package com.wgj.home;

import java.io.*; 


public class FileOperator {
	
	  public FileOperator() {
	  }

	  /**
	   * 新建目录
	   * @param folderPath String 如 c:/fqf
	   * @return boolean
	   */
	  public void newFolder(String folderPath) {
	    try {
	      String filePath = folderPath;
	      filePath = filePath.toString();
	      java.io.File myFilePath = new java.io.File(filePath);
	      if (!myFilePath.exists()) {
	        myFilePath.mkdir();
	      }
	    }
	    catch (Exception e) {
	      System.out.println("新建目录操作出错");
	      e.printStackTrace();
	    }
	  }

	  /**
	   * 新建文件
	   * @param filePathAndName String 文件路径及名称 如c:/fqf.txt
	   * @param fileContent String 文件内容
	   * @return boolean
	   */
	  public void newFile(String filePathAndName, String fileContent) {

	    try {
	      String filePath = filePathAndName;
	      filePath = filePath.toString();
	      File myFilePath = new File(filePath);
	      if (!myFilePath.exists()) {
	        myFilePath.createNewFile();
	      }
	      FileWriter resultFile = new FileWriter(myFilePath);
	      PrintWriter myFile = new PrintWriter(resultFile);
	      String strContent = fileContent;
	      myFile.println(strContent);
	      resultFile.close();

	    }
	    catch (Exception e) {
	      System.out.println("新建目录操作出错");
	      e.printStackTrace();

	    }

	  }

	  /**
	   * 删除文件
	   * @param filePathAndName String 文件路径及名称 如c:/fqf.txt
	   * @param fileContent String
	   * @return boolean
	   */
	  public void delFile(String filePathAndName) {
	    try {
	      String filePath = filePathAndName;
	      filePath = filePath.toString();
	      java.io.File myDelFile = new java.io.File(filePath);
	      myDelFile.delete();

	    }
	    catch (Exception e) {
	      System.out.println("删除文件操作出错");
	      e.printStackTrace();

	    }

	  }

	  /**
	   * 删除文件夹
	   * @param filePathAndName String 文件夹路径及名称 如c:/fqf
	   * @param fileContent String
	   * @return boolean
	   */
	  public void delFolder(String folderPath) {
	    try {
	      delAllFile(folderPath); //删除完里面所有内容
	      String filePath = folderPath;
	      filePath = filePath.toString();
	      java.io.File myFilePath = new java.io.File(filePath);
	      myFilePath.delete(); //删除空文件夹

	    }
	    catch (Exception e) {
	      System.out.println("删除文件夹操作出错");
	      e.printStackTrace();

	    }

	  }

	  /**
	   * 删除文件夹里面的所有文件
	   * @param path String 文件夹路径 如 c:/fqf
	   */
	  public void delAllFile(String path) {
	    File file = new File(path);
	    if (!file.exists()) {
	      return;
	    }
	    if (!file.isDirectory()) {
	      return;
	    }
	    String[] tempList = file.list();
	    File temp = null;
	    for (int i = 0; i < tempList.length; i++) {
	      if (path.endsWith(File.separator)) {
	        temp = new File(path + tempList[i]);
	      }
	      else {
	        temp = new File(path + File.separator + tempList[i]);
	      }
	      if (temp.isFile()) {
	        temp.delete();
	      }
	      if (temp.isDirectory()) {
	        delAllFile(path+"/"+ tempList[i]);//先删除文件夹里面的文件
	        delFolder(path+"/"+ tempList[i]);//再删除空文件夹
	      }
	    }
	  }

	  /**
	   * 复制单个文件
	   * @param oldPath String 原文件路径 如：c:/fqf.txt
	   * @param newPath String 复制后路径 如：f:/fqf.txt
	   * @return boolean
	   */
	  public void copyFile(String oldPath, String newPath) {
	    try {
	      int bytesum = 0;
	      int byteread = 0;
	      File oldfile = new File(oldPath);
	      if (oldfile.exists()) { //文件存在时
	        InputStream inStream = new FileInputStream(oldPath); //读入原文件
	        FileOutputStream fs = new FileOutputStream(newPath);
	        byte[] buffer = new byte[1444];
	        int length;
	        while ( (byteread = inStream.read(buffer)) != -1) {
	          bytesum += byteread; //字节数 文件大小
	          fs.write(buffer, 0, byteread);
	        }
	        inStream.close();
	      }
	    }
	    catch (Exception e) {
	      System.out.println("复制单个文件操作出错");
	      e.printStackTrace();
	    }
	  }

	  /**
	   * 复制整个文件夹内容
	   * @param oldPath String 原文件路径 如：c:/fqf
	   * @param newPath String 复制后路径 如：f:/fqf/ff
	   * @return boolean
	   */
	  public void copyFolder(String oldPath, String newPath) {

	    try {
	      (new File(newPath)).mkdirs(); //如果文件夹不存在 则建立新文件夹
	      File a=new File(oldPath);
	      //System.out.println("oldPath:"+oldPath);
	      String[] file=a.list();
	      File temp=null;
	      for (int i = 0; i < file.length; i++) {
	        if(oldPath.endsWith(File.separator)){
	          temp=new File(oldPath+file[i]);
	        }
	        else{
	          temp=new File(oldPath+File.separator+file[i]);
	        }

	        if(temp.isFile()){
	          FileInputStream input = new FileInputStream(temp);
	          FileOutputStream output = new FileOutputStream(newPath + "/" +
	              (temp.getName()).toString());
	          byte[] b = new byte[1024 * 5];
	          int len;
	          while ( (len = input.read(b)) != -1) {
	            output.write(b, 0, len);
	          }
	          output.flush();
	          output.close();
	          input.close();
	        }
	        if(temp.isDirectory()){//如果是子文件夹
	          copyFolder(oldPath+"/"+file[i],newPath+"/"+file[i]);
	        }
	      }
	    }
	    catch (Exception e) {
	      System.out.println("copying all file error");//复制整个文件夹内容操作出错
	      e.printStackTrace();

	    }
	  }

	  /**
	   * 移动文件到指定目录
	   * @param oldPath String 如：c:/fqf.txt
	   * @param newPath String 如：d:/fqf.txt
	   */
	  public void moveFile(String oldPath, String newPath) {
	    copyFile(oldPath, newPath);
	    delFile(oldPath);

	  }

	  /**
	   * 移动文件到指定目录
	   * @param oldPath String 如：c:/fqf.txt
	   * @param newPath String 如：d:/fqf.txt
	   */
	  public void moveFolder(String oldPath, String newPath) {
	    copyFolder(oldPath, newPath);
	    delFolder(oldPath);

	  }
}