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  • Java中遍历文件夹的2种方法

     A.不使用递归:

      

          import java.io.File;

      import java.util.LinkedList;

      public class FileSystem {

      public static void main(String[] args) {

      long a = System.currentTimeMillis();

      LinkedList list = new LinkedList();

      File dir = new File("c:""java""");

      File file[] = dir.listFiles();

      for (int i = 0; i < file.length; i++) {

      if (file[i].isDirectory())

      list.add(file[i]);

      else

      System.out.println(file[i].getAbsolutePath());

      }

      File tmp;

      while (!list.isEmpty()) {

      tmp = list.removeFirst();

      if (tmp.isDirectory()) {

      file = tmp.listFiles();

      if (file == null)

      continue;

      for (int i = 0; i < file.length; i++) {

      if (file[i].isDirectory())

      list.add(file[i]);

      else

      System.out.println(file[i].getAbsolutePath());

      }

      } else {

      System.out.println(tmp.getAbsolutePath());

      }

      }

      System.out.println(System.currentTimeMillis() - a);

      }

      }

      B.使用递归:

      

          import java.io.File;

      import java.util.ArrayList;

      public class FileSystem1 {

      private static ArrayList filelist = new ArrayList();

      public static void main(String[] args) {

      long a = System.currentTimeMillis();

      refreshFileList("c:""java");

      System.out.println(System.currentTimeMillis() - a);

      }

      public static void refreshFileList(String strPath) {

      File dir = new File(strPath);

      File[] files = dir.listFiles();

      if (files == null)

      return;

      for (int i = 0; i < files.length; i++) {

      if (files[i].isDirectory()) {

      refreshFileList(files[i].getAbsolutePath());

      } else {

      String strFileName = files[i].getAbsolutePath().toLowerCase();

      System.out.println("---"+strFileName);

      filelist.add(files[i].getAbsolutePath());

      }

      }

      }

      }

      结论:经过测试,使用递归的方法B性能相对好一些。

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  • 原文地址:https://www.cnblogs.com/lzhdim/p/1362478.html
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