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How to create a file in a directory in java?

If I want to create a file in C:/a/b/test.txt, can I do something like:

File f = new File("C:/a/b/test.txt");

Also, I want to use FileOutputStream to create the file. So how would I do it? For some reason the file doesn't get created in the right directory.


R
RMT

The best way to do it is:

String path = "C:" + File.separator + "hello" + File.separator + "hi.txt";
// Use relative path for Unix systems
File f = new File(path);

f.getParentFile().mkdirs(); 
f.createNewFile();

Won't work for Linux because there is no such thing as "C:" in unix systems.
Using new File("/a/b/test.txt") works for both systems. On Windows, it will be written to the same disk as where JVM runs.
f.getParentFile().mkdirs(); f.createNewFile();
Don't forget to check the called method (mkdirs and createNewFile) calls for errors
if(!file.exists()) f.createNewFile();
B
BalusC

You need to ensure that the parent directories exist before writing. You can do this by File#mkdirs().

File f = new File("C:/a/b/test.txt");
f.getParentFile().mkdirs();
// ...

佚名

With Java 7, you can use Path, Paths, and Files:

import java.io.IOException;
import java.nio.file.FileAlreadyExistsException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;

public class CreateFile {

    public static void main(String[] args) throws IOException {
        Path path = Paths.get("/tmp/foo/bar.txt");

        Files.createDirectories(path.getParent());

        try {
            Files.createFile(path);
        } catch (FileAlreadyExistsException e) {
            System.err.println("already exists: " + e.getMessage());
        }
    }
}

M
Marcelo

Use:

File f = new File("C:\\a\\b\\test.txt");
f.mkdirs();
f.createNewFile();

Notice I changed the forward slashes to double back slashes for paths in Windows File System. This will create an empty file on the given path.


On Windows, both \\ and / are valid. The createNewFile() is by the way unnecessary when you write to it with FileOutputStream anyway.
@Eric Noted and Corrected, Thank you.
This created a directory called test.txt instead of file.
M
Mayank
String path = "C:"+File.separator+"hello";
String fname= path+File.separator+"abc.txt";
    File f = new File(path);
    File f1 = new File(fname);

    f.mkdirs() ;
    try {
        f1.createNewFile();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
}

This should create a new file inside a directory


M
Mehdi

A better and simpler way to do that :

File f = new File("C:/a/b/test.txt");
if(!f.exists()){
   f.createNewFile();
}

Source


A
AKHY

Create New File in Specified Path

import java.io.File;
import java.io.IOException;

public class CreateNewFile {

    public static void main(String[] args) {
        try {
            File file = new File("d:/sampleFile.txt");
            if(file.createNewFile())
                System.out.println("File creation successfull");
            else
                System.out.println("Error while creating File, file already exists in specified path");
        }
        catch(IOException io) {
            io.printStackTrace();
        }
    }

}

Program Output:

File creation successfull


M
MasterJoe

Surprisingly, many of the answers don't give complete working code. Here it is:

public static void createFile(String fullPath) throws IOException {
    File file = new File(fullPath);
    file.getParentFile().mkdirs();
    file.createNewFile();
}

public static void main(String [] args) throws Exception {
    String path = "C:/donkey/bray.txt";
    createFile(path);
}

K
Kirill Ch

To create a file and write some string there:

BufferedWriter bufferedWriter = Files.newBufferedWriter(Paths.get("Path to your file"));
bufferedWriter.write("Some string"); // to write some data
// bufferedWriter.write("");         // for empty file
bufferedWriter.close();

This works for Mac and PC.


F
Fridjato Part Fridjat

For using the FileOutputStream try this :

public class Main01{
    public static void main(String[] args) throws FileNotFoundException{
        FileOutputStream f = new FileOutputStream("file.txt");
        PrintStream p = new PrintStream(f);
        p.println("George.........");
        p.println("Alain..........");
        p.println("Gerard.........");
        p.close();
        f.close();
    }
}

T
Tom

When you write to the file via file output stream, the file will be created automatically. but make sure all necessary directories ( folders) are created.

    String absolutePath = ...
    try{
       File file = new File(absolutePath);
       file.mkdirs() ;
       //all parent folders are created
       //now the file will be created when you start writing to it via FileOutputStream.
      }catch (Exception e){
        System.out.println("Error : "+ e.getmessage());
       }