java判断两个文件夹是否存在相同的文件

public static void main(String[] args) {
  compare("D:/2-3-4/", "D:/2-3-5-1/");
 }

 public static void compare(String frompath, String topath) {
  Map<String,String> fromMap = new HashMap<String, String>();
  Map<String,String> toMap = new HashMap<String, String>();
  try {
   System.out.println("----------------------fromMap开始----------------------------");
   LinkedList list = new LinkedList();
   File dir = new File(frompath);
   File file[] = dir.listFiles();
   for (int i = 0; i < file.length; i++) {
    if (file[i].isDirectory())
     list.add(file[i]);
    else{
     fromMap.put(file[i].getName(),file[i].getName());
     //System.out.println(file[i].getName());
    }
   }
   System.out.println("----------------------toMap开始----------------------------");
   dir = new File(topath);
   File[] tofile = dir.listFiles();
   for (int i = 0; i < tofile.length; i++) {
    if (tofile[i].isDirectory())//判断读到的是否是文件夹
     list.add(tofile[i]);
    else{
     toMap.put(tofile[i].getName(),tofile[i].getName());
     //System.out.println(tofile[i].getName());
    }
     
   }
   System.out.println("判断toMap中的值是否在fromMap中存在.");
   Iterator it = toMap.entrySet().iterator();
   while(it.hasNext()){
    Map.Entry<String, String> e = (Entry<String, String>) it.next();
    if(fromMap.containsKey(e.getKey())){
    }else{
     System.out.println(e.getKey());
    }
   }
   System.out.println("判断fromMap中的值是否在toMap中存在.");
   Iterator it1 = fromMap.entrySet().iterator();
   while(it1.hasNext()){
    Map.Entry<String, String> e = (Entry<String, String>) it1.next();
    if(toMap.containsKey(e.getKey())){
    }else{
     System.out.println(e.getKey());
    }
   }
  } catch (Exception e) {

   e.printStackTrace();
  }

 }