Question

Write the program in Java.

Description:

Write a program to calculate the total size of all files in the current directory / folder and all sub-folders.

Example:

I have a directory with 1 file (size 150KB) and 2 subdirectories, each of which has 1 file (size 10KB each), then when I run this program on this directory, I expect the answer to be 170KB.

Answer 1

//using the sum of its contents

private long getFolderSize(File folder) {

    long length = 0;

    File[] files = folder.listFiles();

    int count = files.length;

    for (int i = 0; i < count; i++) {

        if (files[i].isFile()) {

            length += files[i].length();

        }

        else {

            length += getFolderSize(files[i]);

        }

    }

    return length;

}

We can test our method getFolderSize() as in the following example:

@Test

public void whenGetFolderSizeRecursive_thenCorrect() {

    long expectedSize = 12607;

    File folder = new File("src/test/resources");

    long size = getFolderSize(folder);

    assertEquals(expectedSize, size);

}

Note: listFiles() is used to list the contents of the given folder.