Java文件操作类

package cn.edu.hbcit.jsj.accp09.bean;import java.io.IOException;import java.io.PrintWriter;import java.io.*;import java.util.*;import java.awt.*;import java.awt.event.*;import java.awt.image.*;import javax.imageio.*;import com.sun.image.codec.jpeg.*;import org.apache.log4j.Logger;/** * <p>Description: 文件操作</p> * * <p>Copyright: Copyright (c) 2009</p> * */public class FileOperate  {protected final Logger log = Logger.getLogger(FileOperate.class.getName());public FileOperate() {// TODO Auto-generated constructor stub}/* * 生成随机文件名 */public String generateRandomFilename(){String RandomFilename = "";Random rand = new Random();//生成随机数int random = rand.nextInt();Calendar calCurrent = Calendar.getInstance();    int intDay = calCurrent.get(Calendar.DATE);    int intMonth = calCurrent.get(Calendar.MONTH) + 1;    int intYear = calCurrent.get(Calendar.YEAR);    String now = String.valueOf(intYear) + "_" + String.valueOf(intMonth) + "_" +        String.valueOf(intDay) + "_";    log.debug("生成于今日的文件名前缀为："+now);        RandomFilename = now + String.valueOf(random > 0 ? random : ( -1) * random) + ".";        return RandomFilename;}/** * 删除文件 * @param fileName * @return boolean */public boolean deleteFile(String fileName){boolean flag = false;try{File delFile = new File(fileName);log.debug("尝试删除："+fileName);flag = delFile.delete();}catch(Exception e){log.error(e);}        return flag;}/** * 为图片添加水印 * @param s 要添加的水印 * @param ImgName 要修改的图片名称及路径 * @param bottom 水印距底边的距离 * @param right 水印距右边的距离 */public void imageWatermark(String s,String ImgName, int right, int bottom){ try{ File _file = new File(ImgName); Image src = ImageIO.read(_file); File img = new File(s); Image imgsrc = ImageIO.read(img); int wideth=src.getWidth(null); int height=src.getHeight(null); BufferedImage image=new BufferedImage(wideth,height,BufferedImage.TYPE_INT_RGB); Graphics g=image.createGraphics(); g.drawImage(src,0,0,wideth,height,null); //String s="要加的水印"; g.setColor(Color.LIGHT_GRAY); g.setFont(new Font("Britannic Bold",Font.ITALIC,18)); //g.setFont(new Font("Arial Black",Font.ITALIC,18)); //Font aa=new Font("宋体",Font.PLAIN,20); //g.drawString(s,wideth-right,height-bottom);g.drawImage(imgsrc, wideth-right,height-bottom,null);g.dispose(); FileOutputStream out=new FileOutputStream(ImgName); JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out); encoder.encode(image); out.close(); } catch(Exception e){ System.out.println(e); } } }