Calculating Folder Size In Java

The following piece of java code demonstrates how we can calculate the size of a given folder using Java Application. This uses a recursive technique. We start with a root directory, and start listing the files/folder. If a file is found, we calculate its size and sum of total size and also increase the total number of files counted so far, if it is a directory, we further do the recursion.

This program has been fully compiled and tested to find the folder size in Java.

/**
 * @author Kushal Paudyal
 * www.sanjaal.com/java
 * Last Modified On: 30th August 2008
 */
package com.kushal.utilities;

import java.io.File;
import java.text.DecimalFormat;
import java.text.NumberFormat;

public class TopLevelFolderSize {

	int totalFolderCount=0;
	int totalFileCount=0;

	public static void main(String args [])
	{
		/**
		 * Define your folder here. This is the folder whose size
		 * statistics you want to find out.
		 */
		String folder = "C:/Users/kushal/Desktop/tempKushal";

		try{
			DecimalFormat fmt =new DecimalFormat("#.##");

			TopLevelFolderSize fg=new TopLevelFolderSize();

			/**Calculating the file size. By default size in long
			 * is returned.
			 */
			long fileSizeByte=fg.getFileSize(new File(folder));

			/**
			 * Formatting the long value to calculate size in
			 * different units KB, MB and GB
			 */
			double fileSizeKB=Double.valueOf(fmt.format(fileSizeByte /1024));
			double fileSizeMB=Double.valueOf(fmt.format(fileSizeByte /(1024*1024)));
			double fileSizeGB=Double.valueOf(fmt.format(fileSizeByte /(1024*1024*1024)));

			/**Printing the statistics**/
			System.out.println("\n\n##############--Folder Statistics--#################");
			System.out.println("Total Folder Size: ["+fileSizeByte+" Bytes] \n\t\t["
						+fileSizeKB+" KB] \n\t\t["
						+fileSizeMB+" MB] \n\t\t["
						+fileSizeGB+" GB]");
			System.out.println("Total Number of Folders: "+fg.getTotalFolderCount());
			System.out.println("Total Number of Files: "+fg.getTotalFileCount());
			System.out.println("##########--End Of Folder Statistics--##############");

		}catch (Exception e)
		{
			System.out.println("Exception Occurred: "+e.getMessage());
		}
	}

	/**
	 * This is a recursive method.
	 * If file is found, total file size is calculated.
	 * If it is a folder, we recurse further.
	 */
	public long getFileSize(File folder) {
		totalFolderCount++; //Counting the total folders

		System.out.println("Processing " + folder.getName());
		long foldersize = 0;

		File[] filelist = folder.listFiles();
		for (int i = 0; i < filelist.length; i++) {
			if (filelist[i].isDirectory()) {
				foldersize += getFileSize(filelist[i]);
			} else {
				totalFileCount++; //Counting the total files
				foldersize += filelist[i].length();
			}
		}

		return foldersize;
	}

	/**
	 * @return the totalFolderCount
	 */
	public int getTotalFolderCount() {
		return totalFolderCount;
	}

	/**
	 * @return the totalFileCount
	 */
	public int getTotalFileCount() {
		return totalFileCount;
	}

}

———————————————————————
SAMPLE OUTPUT:
———————————————————————
Processing tempKushal
Processing cute pictures
Processing image col
Processing Moline Tornado
Processing send
Processing Party At Prabhakars
Processing images

##############–Folder Statistics–#################
Total Folder Size: [151850658 Bytes]
[148291.0 KB]
[144.0 MB]
[0.0 GB]
Total Number of Folders: 7
Total Number of Files: 154
##########–End Of Folder Statistics–##############