Use of the file class in Java

public class Filelei {

public static void Main (string[] args) throws IOException {
//.. Represents the previous level of directory. Indicates the current directory
File File = new File ("C:\\users\\cdlx2016\\desktop\\file class");
System.out.println ("Whether the file exists:" +file.exists ());

File File1 = new File (".. \\a.txt ");
System.out.println (File1.getabsolutepath ());
System.out.println ("Whether the file exists:" +file1.exists ());

Creates an empty file at the specified location and cannot create a
File File2 = new File ("C:\\users\\cdlx2016\\desktop\\file class \\aa");
System.out.println ("Creates an empty file with the specified path:" +file2.createnewfile ());

File File3 = new File ("C:\\users\\cdlx2016\\desktop\\file class \\CC");
System.out.println ("Whether to create success:" +file3.mkdir ());

File File4 = new File ("C:\\users\\cdlx2016\\desktop\\file class \\dd");
System.out.println ("Whether to create success:" +file4.mkdirs ());

Renaming
File File5 = new File ("C:\\users\\cdlx2016\\desktop\\file class \\a.txt");
System.out.println ("Whether the file exists:" +file5.exists ());
File File6 = new File ("C:\\users\\cdlx2016\\desktop\\file class \\abc.txt");
System.out.println ("Rename succeeded:" +file5.renameto (File6));

Change the drive letter
File File7 = new File ("C:\\users\\cdlx2016\\desktop\\file class \\abc.txt");
System.out.println ("Change succeeded:" +file7.renameto (New File ("D:\\abc.txt"));

Delete, which is deleted when the JVM exits.
File File8 = new File ("C:\\users\\cdlx2016\\desktop\\file class \\abc.txt");
System.out.println ("Delete succeeded:" +file8.delete ());

Decide if it's a file or a folder
File File9 = new File ("C:\\users\\cdlx2016\\desktop\\file class \\aa");
System.out.println ("Whether it is a file:" +file9.isfile ());
System.out.println ("Is folder:" +file9.isdirectory ());
System.out.println ("Whether Hidden:" +file9.ishidden ());
System.out.println ("is absolute path:" +file9.isabsolute ());

See if a folder contains hidden folders or files
1. By getting all the files or folders
2. Finally, the Ishidden () method is used to determine
System.out.println ("Get Name:" +file9.getname ());
SYSTEM.OUT.PRINTLN ("Get Path:" +file9.getpath ());
System.out.println ("Get absolute Path:" +file9.getabsolutepath ());

Gets the size of the file in bytes
File File10 = new File ("C:\\users\\cdlx2016\\desktop\\file class \\ab.txt");
System.out.println ("Get File Size:" +file10.length ());
System.out.println ("Get Parent Directory:" +file10.getparent ());

Gets the time, in milliseconds, for the last modification
Long time = file10.lastmodified ();
Date date = new Date (time);
SimpleDateFormat DateFormat = new SimpleDateFormat ("Yyyy-mm-dd HH:mm:ss");
System.out.println ("Last Modified Time:" +dateformat.format (date));

Operation of the folder
file[] files = file.listroots ();//Get all the drive characters in your computer
for (File f:files) {
SYSTEM.OUT.PRINTLN ("drive letter" +f);
}

Gets the files and subdirectories under the specified folder (contains hidden)
File File11 = new File ("C:\\users\\cdlx2016\\desktop\\file class");
string[] namestring = File.list ();
for (String str:namestring) {
System.out.println (str);
}

File File12 = new file ("C:\\users\\cdlx2016\\desktop\\java section (javase)");
file[] Files2 = File12.listfiles ();
for (File file13:files2) {
if (File13.isdirectory ()) {

}else{
System.out.println (File13.getname ());
}
}

View the file with the specified suffix name
File File14 = new File ("C:\\users\\cdlx2016\\desktop\\file class");
string[] strings01 = file14.list (New Myfilter ());
for (String str01:strings01) {
System.out.println (STR01);
}
}
}

Class Myfilter implements filenamefilter{
@Override
Public Boolean Accept (File dir, String name) {
The idea is to intercept the last point after the string and the. Javajava do a comparison
Name = name.substring (Name.lastindexof ('. ') +1));
Return "TXT". Equals (name);
}
}

Use of the file class in Java