The size of files in Java can be obtained using the File class. The in-built function of ‘fileName.length()’ is used to find size of file in Bytes. The directory may contain ‘N’ number of files, for calculating the size of the directory summation of the size of all the files is required.
length() Method:
length() method in the object of the file class is returning the file size in long(datatype) format. The file size is in a unit of Byte.
Return Type: long
Syntax:
java.io.File file = new java.io.File("file_name.txt"); file.length();
Working:
- If the file exists then the function return the size of the file
- Else the function returns null.
However, the size of the file can be display in Mega, Kilo units using unit conversion.
Java
// Java program to Get the size of a directory import java.io.File; class GFG { private static long getFolderSize(File folder) { long length = 0 ; // listFiles() is used to list the // contents of the given folder File[] files = folder.listFiles(); int count = files.length; // loop for traversing the directory for ( int i = 0 ; i < count; i++) { if (files[i].isFile()) { length += files[i].length(); } else { length += getFolderSize(files[i]); } } return length; } // Driver Code public static void main(String[] args) { // Creating an instances of file class File file1 = new File( "/home/mayur/Downloads" ); long size = getFolderSize(file1); // Size of folder in Bytes System.out.println( "Size of " + file1 + " is " + size + " B" ); // Size of folder in Kilobytes System.out.println( "Size of " + file1 + " is " + ( double )size / 1024 + " KB" ); // Size of folder in Megabytes System.out.println( "Size of " + file1 + " is " + ( double )size / ( 1024 * 1024 ) + " MB" ); } } |