如何通过Java读取文件夹中的所有文件?这与哪个API无关。


当前回答

package com;


import java.io.File;

/**
 *
 * @author ?Mukesh
 */
public class ListFiles {

     static File mainFolder = new File("D:\\Movies");

     public static void main(String[] args)
     {
         ListFiles lf = new ListFiles();
         lf.getFiles(lf.mainFolder);

         long fileSize = mainFolder.length();
             System.out.println("mainFolder size in bytes is: " + fileSize);
             System.out.println("File size in KB is : " + (double)fileSize/1024);
             System.out.println("File size in MB is :" + (double)fileSize/(1024*1024));
     }
     public void getFiles(File f){
         File files[];
         if(f.isFile())
             System.out.println(f.getAbsolutePath());
         else{
             files = f.listFiles();
             for (int i = 0; i < files.length; i++) {
                 getFiles(files[i]);
             }
         }
     }
}

其他回答

import java.io.File;


public class ReadFilesFromFolder {
  public static File folder = new File("C:/Documents and Settings/My Documents/Downloads");
  static String temp = "";

  public static void main(String[] args) {
    // TODO Auto-generated method stub
    System.out.println("Reading files under the folder "+ folder.getAbsolutePath());
    listFilesForFolder(folder);
  }

  public static void listFilesForFolder(final File folder) {

    for (final File fileEntry : folder.listFiles()) {
      if (fileEntry.isDirectory()) {
        // System.out.println("Reading files under the folder "+folder.getAbsolutePath());
        listFilesForFolder(fileEntry);
      } else {
        if (fileEntry.isFile()) {
          temp = fileEntry.getName();
          if ((temp.substring(temp.lastIndexOf('.') + 1, temp.length()).toLowerCase()).equals("txt"))
            System.out.println("File= " + folder.getAbsolutePath()+ "\\" + fileEntry.getName());
        }

      }
    }
  }
}

使用Java 1.7来递归列出命令行指定目录中的文件的简单示例:

import java.io.File;

public class List {
    public static void main(String[] args) {
        for (String f : args) {
            listDir(f);
        }
    }

    private static void listDir(String dir) {
        File f = new File(dir);
        File[] list = f.listFiles();

        if (list == null) {
            return;
        }

        for (File entry : list) {
            System.out.println(entry.getName());
            if (entry.isDirectory()) {
                listDir(entry.getAbsolutePath());
            }
        }
    }
}

从Test文件夹中列出类路径内的文件

import java.io.File;
import java.io.IOException;

public class Hello {

    public static void main(final String[] args) throws IOException {

        System.out.println("List down all the files present on the server directory");
        File file1 = new File("/prog/FileTest/src/Test");
        File[] files = file1.listFiles();
        if (null != files) {
            for (int fileIntList = 0; fileIntList < files.length; fileIntList++) {
                String ss = files[fileIntList].toString();
                if (null != ss && ss.length() > 0) {
                    System.out.println("File: " + (fileIntList + 1) + " :" + ss.substring(ss.lastIndexOf("\\") + 1, ss.length()));
                }
            }
        }


    }


}

给定一个baseDir,列出它下面的所有文件和目录,迭代编写。

    public static List<File> listLocalFilesAndDirsAllLevels(File baseDir) {

    List<File>  collectedFilesAndDirs   = new ArrayList<>();
    Deque<File> remainingDirs           = new ArrayDeque<>();

    if(baseDir.exists()) {
        remainingDirs.add(baseDir);

        while(!remainingDirs.isEmpty()) {
            File dir = remainingDirs.removeLast();
            List<File> filesInDir = Arrays.asList(dir.listFiles());
            for(File fileOrDir : filesInDir)  {
                collectedFilesAndDirs.add(fileOrDir);
                if(fileOrDir.isDirectory()) {
                    remainingDirs.add(fileOrDir);
                }
            }
        }
    }

    return collectedFilesAndDirs;
}

这将很好地工作:

private static void addfiles(File inputValVal, ArrayList<File> files)
{
  if(inputVal.isDirectory())
  {
    ArrayList <File> path = new ArrayList<File>(Arrays.asList(inputVal.listFiles()));

    for(int i=0; i<path.size(); ++i)
    {
        if(path.get(i).isDirectory())
        {
            addfiles(path.get(i),files);
        }
        if(path.get(i).isFile())
        {
            files.add(path.get(i));
        }
     }

    /*  Optional : if you need to have the counts of all the folders and files you can create 2 global arrays 
        and store the results of the above 2 if loops inside these arrays */
   }

   if(inputVal.isFile())
   {
     files.add(inputVal);
   }

}