How to create a directory in Java?

Question

How do I create Directory/folder?

Once I have tested System.getProperty("user.home");

I have to create a directory (directory name "new folder" ) if and only if new folder does not exist.

Answer 1

1. Create a single directory.

   new File("C:\\Directory1").mkdir();
   

2. Create a directory named “Directory2 and all its sub-directories “Sub2″ and “Sub-Sub2″ together.

   new File("C:\\Directory2\\Sub2\\Sub-Sub2").mkdirs()
   

Source: this perfect tutorial , you find also an example of use.

Answer 2

if you want to be sure its created then this:

final String path = "target/logs/";
final File logsDir = new File(path);
final boolean logsDirCreated = logsDir.mkdir();
if (!logsDirCreated) {
    final boolean logsDirExists = logsDir.exists();
    assertThat(logsDirExists).isTrue();
}

beacuse mkDir() returns a boolean, and findbugs will cry for it if you dont use the variable. Also its not nice...

mkDir() returns only true if mkDir() creates it. If the dir exists, it returns false, so to verify the dir you created, only call exists() if mkDir() return false.

assertThat() will checks the result and fails if exists() returns false. ofc you can use other things to handle the uncreated directory.

Answer 3

You can try FileUtils#forceMkdir

FileUtils.forceMkdir("/path/directory");

This library have a lot of useful functions.

Answer 4

For java 7 and up:

Path path = Paths.get("/your/path/string");
if(!Files.exists(path)) {
    try {
      Files.createDirectories(path);
    } catch (IOException e) {
      e.printStackTrace();
    }
}

Answer 5

This the way work for me do one single directory or more or them: need to import java.io.File;
/*enter the code below to add a diectory dir1 or check if exist dir1, if does not, so create it and same with dir2 and dir3 */

    File filed = new File("C:\\dir1");
    if(!filed.exists()){  if(filed.mkdir()){ System.out.println("directory is created"); }} else{ System.out.println("directory exist");  }

    File filel = new File("C:\\dir1\\dir2");
    if(!filel.exists()){  if(filel.mkdir()){ System.out.println("directory is created");   }} else{ System.out.println("directory exist");  }

    File filet = new File("C:\\dir1\\dir2\\dir3");
    if(!filet.exists()){  if(filet.mkdir()){ System.out.println("directory is  created"); }}  else{ System.out.println("directory exist");  }