File operations in java

Files in Java

java provides java.io.File class for handling file / directories  operations .

Creating a File object :

File file = new File(“file1.txt”);

A File object represents name and path of a file or directory on a Disk. In the above code just File

object has been created actual file is not yet created in the current directory. If you don’t know the

current directory you can get it this way:

String userdir = System.getProperty(“user.dir”);   //returns user current directory.

 Check the existance of File or Directory

1) boolean exists() – Checks whether file exist or not

2) boolean isFile() – Checks it is a file or not.

3) boolean isDirectory() – Checks it is a directory or not.

4) String[] list() – return the names of all files and directories in a directory

5) String getName() – returns file or directory’s name

6) String getPath() – returns file or directory’s path.

 

Below are the examples given to create file/directories, deleting file/directories, renaming and copying files.

 

Creating a Directory:

You can create a Directory using the method mkdir() , lets create a directory mydir using the below code

 

Creating a file:

In java, file is created using createNewFile() method. Below is the example to create a file.

Output :

false

true

Creating a Directory:

We can create a directory using mkdir() method. Creating a directory and file is shown below

Output: File “myfile.txt” will be created under mydir.

Renaming a File:

Current directory contains the file named “file1”, we will rename it to “file2”.

Output: file name file1 will be renamed to file2 in current directory.

Deleting a File:

Output: File “file1.txt” deleted from current directory.

Deleting a file from a specific directory

Output : “file1.txt” get deleted from the mydir.

Deleting all the files in a Deirectory:

Below code will show you how to delete all the files in a Directory

Copying Files:

In java files can be copied using copyfile method which copies content of one file to another file.