File类遍历目录

1,将遍历的目录保存至List并输出

package com.study.FileDemo;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.PrintStream;
import java.util.ArrayList;
import java.util.List;
/**
 * 
 * 遍历目录输出至文件 
 *
*/
public class ListFileDemo01 {

    public static void main(String[] args) {
        List<String> lst = ListFileTest(new File("d:" + File.separator));
        PrintStream ps = null;
        try {
            ps = new PrintStream(new FileOutputStream(new File("e:"
                    + File.separator + "fadfafa223.txt")));
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
        for (String s : lst) {
            ps.println(s);
        }

    }

    public static List<String> ListFileTest(File file) {
        File[] f = file.listFiles();
        List<String> list = new ArrayList<String>();
        if (f != null) {
            for (int i = 0; i < f.length; i++) {
                if (f[i].isDirectory()) {
                    list.addAll(ListFileTest(f[i]));//这句很关键
                } else {
                    list.add(f[i].getPath());
                }
            }
        }
        return list;

    }
}

2,将遍历的目录树状显示

import java.io.File;

public class ListTest03 {

    public static void main(String[] args) {
        listFile("d:\\DG343Std_x86", 1);

    }

    public static void listFile(String dir, int level) {
        File f = new File(dir);
        for (int i = 0; i <= level; i++) {
            System.out.print("| ");
        }
        System.out.println("|-" + f.getName());
        if (f.isDirectory()) {
            File fs[] = f.listFiles();
            for (File s : fs) {
                listFile(s.getPath(), level + 1);
            }
        }
    }

}