根据路径替换String

package com.chenjin.study.file;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.LineNumberReader;

/**
 * <p>标题: 替换文件夹内字符串</p>
 * <p>说明: </p>
 * <p>版本: Copyright (c) 2008-11-11</p>
 * <p>创建: 2008-11-11 上午08:38:42
 * @author cj
 */
public class ReplaceString {
	
	/** 缓冲区大小 */
	private static final int SIZE = 8 * 1024;
	
	
	/**
	 * <p>【按路径替换】</p>
	 * @param path
	 * @param oldStr
	 * @param newStr
	 * @author:cj  [2008-11-16 下午03:36:54]
	 */
	public static void replaceByPath(String path, String oldStr, String newStr) {
		File file = new File(path);
		if (!file.exists()) {
			System.err.println((new StringBuilder("file not found: ")).append(
					path).toString());
			return;
		} else {
			replaceByFile(file,oldStr,newStr);
		}
	}
	
	/**
	 * <p>【按文件替换，可以为文件夹】</p>
	 *
	 * @param file
	 * @param oldStr
	 * @param newStr
	 * @author:cj  [2008-11-16 下午03:37:07]
	 */
	public static void replaceByFile(File file, String oldStr, String newStr){
		if(file==null||oldStr==null||oldStr.equalsIgnoreCase(""))
			return ;
		if(file.isDirectory()){
            File files[] = file.listFiles();
            for(int i = 0; i < files.length; i++)
            	replaceByFile(files[i], oldStr,newStr);		
            return;
		}
		FileInputStream input = null;
		LineNumberReader reader = null;
        FileWriter fw = null;
        StringBuffer buffer = new StringBuffer();
		try {
			input = new FileInputStream(file);
			// 读数据
			reader = new LineNumberReader(new InputStreamReader(input), SIZE);
			String s = null;
			while ((s = reader.readLine()) != null) {
				buffer.append(replaceByString(s, oldStr ,newStr)).append("\n");
			}
			fw = new FileWriter(file);
            fw.write(buffer.toString());
			
		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch(Exception e){
			e.printStackTrace();
		} finally {
			if (reader != null) {
				try {
		            fw.close();
					reader.close();
				} catch (IOException e) {

				}catch(Exception e){
					
				}
			}
			if (input != null) {
				try {
					input.close();
				} catch (IOException e) {

				}catch(Exception e){
					
				}
			}
		}
	}
	
	public static String replaceByString(String str,String oldStr,String newStr) {
		return str.replaceAll(oldStr, newStr);
	}
	
	public static void main(String[] args) {
		String path="D:/zycms/wwwroot/jhzfxxgk/web";
		ReplaceString.replaceByPath(path, "src", "src=");
	}
}

感觉不是很好，希望能在取出文件同时改变。