Get size of folder or file

Question

How can I retrieve size of folder or file in Java?

Answer 1

public long folderSize (String directory)
    {
        File curDir = new File(directory);
        long length = 0;
        for(File f : curDir.listFiles())
        {
            if(f.isDirectory())
            {               
                 for ( File child : f.listFiles()) 
                 {
                     length = length + child.length();
                 }

                System.out.println("Directory: " + f.getName() + " " + length + "kb");
            }
            else
            {
                length = f.length();
                System.out.println("File: " + f.getName() + " " + length + "kb");
            }
            length = 0;
        }
        return length;
    }

Answer 2

public static long getFolderSize(File dir) {
    long size = 0;
    for (File file : dir.listFiles()) {
        if (file.isFile()) {
            System.out.println(file.getName() + " " + file.length());
            size += file.length();
        }
        else
            size += getFolderSize(file);
    }
    return size;
}