Java 批量修改文件后缀

import java.io.*;  
 
public class test {  
   
  public void reName(String path, String from, String to) {  
    File f = new File(path);  
    File[] fs = f.listFiles();  
  
    for (int i = 0; i < fs.length; ++i) {  
      File f2 = fs[i];  
     
      if (f2.isDirectory()) {  
        reName(f2.getPath(), from, to);  
      } else {  
        String name = f2.getName();
          if (name.endsWith(from)) {  
          f2.renameTo(new File(f2.getParent() + "/" + name.substring(0, name.indexOf(from)) + to));  
        }  
      }  
    }  
  }  
  public static void main(String[] args) {  
   test rf = new test();  
    rf.reName("C:/Documents and Settings/xxxxx/Desktop/astaxie", ".md",".txt");  
  }  
}