java文件File，FileMethod知识点总结

1. File file = new File(“E:\黑马\java基础\已看\day19\video\File\19.14_File类(File类的概述和构造方法).avi”);

2. String parent = “E:\黑马\java基础\已看\day19\video”;
   String child = “File\19.14_File类(File类的概述和构造方法).avi”;

   File file = new File( parent, child);
   

3. File file = new File(“zhouxiaowei.txt”);
   System.out.println(file.createNewFile());
   file.setReadable(false);
   System.out.println(file.canRead());
   file.setWritable(false);
   System.out.println(file.canWrite());
   System.out.println(file.isHidden());

   File dir = new File("airen");
   dir.mkdir();
   File dir2 = new File("aini\\xiaowei");
   dir2.mkdirs();
   
   File file1 = new File("guyulei.txt");
   File file2 = new File("guyulei1109.txt");
   file1.renameTo(file2);
   
   System.out.println(dir.isDirectory());
   

4. File file = new File(“guyulei1109.txt”);
   System.out.println(file.getAbsolutePath());
   System.out.println(file.getPath());
   System.out.println(file.getName());
   System.out.println(file.length());
   System.out.println(file.lastModified());

5. Date date = new Date(file.lastModified());
   SimpleDateFormat sdf = new SimpleDateFormat(“yyyy年MM 月dd日 HH:mm:ss”);
   //System.out.println(data);
   System.out.println(sdf.format(date));

6. File dir = new File(“E:\黑马\java基础\已看\day19\video\File”);
   String [] arr = dir.list();
   for (String str : arr) {
   System.out.println(str);
   }

   File [] subFiles = dir.listFiles();
   for (File f : subFiles) {
       System.out.println(f);
   }
   

7. File file = new File(“E:\黑马\java基础\已看\day19\video\file”);
   /*String arr[] = file.list();
   for (String str : arr) {
   if (str.endsWith(“.avi”)){
   System.out.println(str);
   }
   }*/
   File [] subFile = file.listFiles();
   for (File f : subFile) {
   if(f.isFile() && f.getName().endsWith(“.avi”)){
   System.out.println(f);
   }
   }

8. String arr[] = file.list(new FilenameFilter() {

       @Override
       public boolean accept(File dir, String name) {
           File file = new File (dir,name);
           return file.isFile() && file.getName().endsWith(".avi");
       }
   });