java批量更改html到jsp

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.InputStreamReader;
 
public class HtmlTransJspUtils {
    public static void main(String[] args) throws Exception {
        //
        File f = new File("指定的目录文件夹");
        for(File s : f.listFiles()){
            String str = s.getAbsolutePath();
            if(str.endsWith(".html")){
                writeFile(str);
                fileRename(str);
            }
            
        }
    }
 
    /**
     * 读取指定文件下的内容，乱码问题已经处理,编码为UTF-8
     * 
     * @param fileName
     * @return
     * @throws Exception
     */
    public static String readFile(String fileName) throws Exception {
        String result = "";
        InputStreamReader inputStreamReader = null;
        BufferedReader bufferedReader = null;
        try {
            inputStreamReader = new InputStreamReader(new FileInputStream(
                    fileName), "utf-8");
            bufferedReader = new BufferedReader(inputStreamReader);
            try {
                String read = null;
                while ((read = bufferedReader.readLine()) != null) {
                    result = result + read + "\r\n";
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (bufferedReader != null) {
                bufferedReader.close();
            }
            if (inputStreamReader != null) {
                inputStreamReader.close();
            }
        }
        System.out.println("读取出来的文件内容是：" + "\r\n" + result);
        return result;
 
    }
 
    /**
     * 文件的写入
     * 
     * @param fileName
     * @throws Exception
     */
    public static void writeFile(String fileName) throws Exception {
        try {
            String oldContent = readFile(fileName);
            FileOutputStream fo = new FileOutputStream(fileName);
            //读取头文件的内容
            fo.write(readFile("F:/head.txt").getBytes("utf-8"));
            fo.write(oldContent.getBytes("utf-8"));
            fo.close();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
    }
 
    /**
     * 修改文件的后缀名，即html变成jsp
     * @param fileName
     */
    public static void fileRename(String fileName) {
        File oldFile = new File(fileName);
        System.out.println("修改前文件名称是：" + oldFile.getName());
        String rootPath = oldFile.getParent();
        System.out.println("根路径是：" + rootPath);
        File newFile = new File(rootPath , oldFile.getName().replace("html", "jsp"));
        System.out.println("修改后文件名称是：" + newFile.getName());
        if (oldFile.renameTo(newFile)) {
            System.out.println("修改成功!");
        } else {
            System.out.println("修改失败");
        }
    }
 
}