Trees - Data Structures and Problem Solving Using Java - page 659

1 import java.io.File;
2
3 public class FileSystem
4 {
5 // Output file name with indentation
6 public static void printName( String name, int depth )
7 {
8 for( int i = 0; i < depth; i++ )
9 System.out.print( " " );
10 System.out.println( name );
11 }
12
13 // Public driver to list all files in directory
14 public static void listAll( File dir )
15 {
16 listAll( dir, 0 );
17 }
18
19 // Recursive method to list all files in directory
20 private static void listAll( File dir, int depth )
21 {
22 printName( dir.getName( ), depth );
23
24 if( dir.isDirectory( ) )
25 for( File child : dir.listFiles( ) )
26 listAll( child, depth + 1 );
27 }
28
29 public static long size( File dir )
30 {
31 long totalSize = dir.length( );
32
33 if( dir.isDirectory( ) )
34 for( File child : dir.listFiles( ) )
35 totalSize += size( child );
36
37 return totalSize;
38 }
39
40 // Simple main to list all files in current directory
41 public static void main( String [ ] args )
42 {
43 File dir = new File( "." );
44 listAll( dir );
45 System.out.println( "Total bytes: " + size( dir ) );
46 }
47 }

figure 18.10
Java implementation
for a directory listing