目錄的遞歸遍歷

package io9;

import java.io.*;
import java.util.ArrayList;
import java.util.Arrays;
import lang9.Str9;
import lang9.out;
//以上引入的lang9中的類很簡單，讀者可自行編寫

public class File9 {
  //list specified files  int dir,include all the specified files in subdirectory.
//  public static File[] listFiles(FileFilter9 filter, File dir) {
//listFilenames
  public static String[] listFilenames(String dir) {
    File[] ff = listFiles(new File(dir));
    String[] ss = new String[ff.length];
    for (int i = 0; i < ff.length; i++) {
      ss[i] = ff[i].getAbsolutePath();
    }
    return ss;
  }

//listfiles()
  public static File[] listFiles() {
    File dir = new File(System.getProperty("user.dir"));
    return listFiles(dir);
  }

//listdirs()
  public static File[] listDirs() {
    File dir = new File(System.getProperty("user.dir"));
    return listDirs(dir);
  }

//listfiles(dir)
  public static File[] listFiles(File dir) {
    if (!dir.exists() || !dir.isDirectory()) {
      System.out.println("wrong File 23");
      return null;
    }

    FileFilter9 filter = new FileFilter9(FileFilter9.FILE);
    ArrayList array = list2ArrayList(filter, dir);
    if (array == null) {
      return null;
    }
    File[] files = new File[array.size()];
    files = (File[]) array.toArray(files);
    return files;
  }

  public static File[] listFiles(String pattern) {
    return listFiles(pattern,new File(System.getProperty("user.dir")));
  }

//listfiles(pattern,dir
  public static File[] listFiles(String pattern, File dir) {
    if (!dir.exists() || !dir.isDirectory()) {
      System.out.println("wrong File 23");
      return null;
    }

    FileFilter9 filter = new FileFilter9(pattern, FileFilter9.FILE);
    ArrayList array = list2ArrayList(filter, dir);
    if (array == null) {
      return null;
    }
    File[] files = new File[array.size()];
    files = (File[]) array.toArray(files);
    return files;
  }

  public static File[] listDirs(File dir) {
    if (!dir.exists() || !dir.isDirectory()) {
      System.out.println("wrong File 23");
      return null;
    }

    FileFilter9 filter = new FileFilter9(FileFilter9.DIR);
    ArrayList array = list2ArrayList(filter, dir);
    if (array == null) {
      return null;
    }
    File[] files = new File[array.size()];
    files = (File[]) array.toArray(files);
    return files;
  }

  public static File[] listDirs(String pattern, File dir) {

    if (!dir.exists() || !dir.isDirectory()) {
      System.out.println("wrong File 23");
      return null;
    }
    FileFilter filter = new FileFilter9(pattern, FileFilter9.DIR);
    ArrayList array = list2ArrayList(filter, dir);
    if (array == null) {
      return null;
    }
    File[] files = new File[array.size()];
    files = (File[]) array.toArray(files);
    return files;
  }

  public static File[] list(File dir) {
    if (!dir.exists() || !dir.isDirectory()) {
      System.out.println("wrong File 24");
      return null;
    }

    FileFilter filter = new FileFilter9(FileFilter9.BOTH);
    ArrayList array = list2ArrayList(filter, dir);
    if (array == null) {
      return null;
    }
    File[] files = new File[array.size()];
    files = (File[]) array.toArray(files);
    return files;
  }

  public static File[] list(String pattern, File dir) {
    if (!dir.exists() || !dir.isDirectory()) {
      System.out.println("wrong File 25");
      return null;
    }

    FileFilter filter = new FileFilter9(pattern, FileFilter9.BOTH);
    ArrayList array = list2ArrayList(filter, dir);
    if (array == null) {
      return null;
    }
    File[] files = new File[array.size()];
    files = (File[]) array.toArray(files);
    return files;
  }

  public static ArrayList list2ArrayList(FileFilter filter, File dir) {
    if (filter == null) {
      filter = new FileFilter9(FileFilter9.BOTH);
    }
    if (dir.isFile()) {
      System.out.println("wrong File9.11");
      return null;
    }
    int i, j;
    File[] specify, dirs; //specify means files or dirs specified by the invoker.
    FileFilter9 filterDir = new FileFilter9(1);
    ArrayList array = new ArrayList();
    specify = dir.listFiles(filter);
    dirs = dir.listFiles(filterDir);
    if (specify != null) {
      for (i = 0; i < specify.length; i++) {
        array.add(specify[i]);
      }
    }
    ArrayList array1;
    if (dirs != null) {
      for (i = 0; i < dirs.length; i++) {
        array1 = File9.list2ArrayList(filter, dirs[i]);
        if (array1 != null) {
          array.addAll(array1);
        }
      }
    }
    return array;
  }

  public static String getRelativePath(File file, File dir) {
    String sFile, sDir;
    if (file == null) {
      System.out.println("wrong,file9.33");
      return null;
    }
    sFile = file.getAbsolutePath();
    if (dir == null) {
      return sFile;
    }
    sDir = dir.getParentFile().getAbsolutePath();
    return Str9.replaceAll(sDir, "", sFile);
  }

//firstName(;
  public static String firstName(File f) {
    int i = f.getName().lastIndexOf(".");
    if (i > 0)
      return f.getName().substring(0, i);
    return null;
  }

//lastName(;
  public static String lastName(File f) {
    int i = f.getName().lastIndexOf(".");
    return f.getName().substring(i + 1);
  }

  public static String firstName(String s) {
    return s.substring(0, s.lastIndexOf("."));
  }

  public static String lastName(String s) {
    return s.substring(s.lastIndexOf(".") + 1);
  }

//createNew()
  public static File createNew() {
    while (true) {
      File f = new File(String.valueOf(Math.random()));
      if (!f.exists())
        return f;
    }
  }
  public static File createNew(String pre) {
    int i=1;
    while (true) {
      File f = new File(pre + i++);
      if (!f.exists())
        return f;
    }
  }

  public static File oldest(String pattern) {
    return oldest(pattern, new File(System.getProperty("user.dir")));
  }

//oldest(pattern,dir)
  public static File oldest(String pattern, File dir) {
    File[] ff = listFiles(pattern, dir);
    long l1 = Long.MAX_VALUE, l2;
    int k = 0;
    for (int i = 0; i < ff.length; i++) {
      l2 = ff[i].lastModified();
      if (l1 > l2) {
        k = i;
        l1 = l2;
      }
    }
    return ff[k];
  }

//exchange
  public static boolean exchange(File f, File ff) {
    return exchangeName(f, ff);
  }

  public static boolean exchangeName(File f, File ff) {
    int i, j, k;
    File f1;
    do {
      File f2 = new File(String.valueOf(Math.random()));
      if (!f2.exists()) {
        f1 = f2;
        break;
      }
    }
    while (true);
    if (f.renameTo(f1)) {
      if (ff.renameTo(f)) {
        if (f1.renameTo(ff))
          return true;
      }
    }
    return false;
  }
  //rename
  public static boolean rename(File d1,File d2){
    
    File[] files=d1.listFiles();
    if(d2.exists()) {
            out.b("alreday exists!");
            return false;
    }
    d2.mkdirs();
    String d2s=d2.getPath();
    for(int i=0;i<files.length;i++){
            if(!files[i].renameTo(new File(d2s+"//"+files[i].getName())))
             return false;
    }
    return true;
  }
  
           
                  
}