FileSystemPath

// 2012-08-03 johnpfeiffer parsing filesystem path and filename
// TODO: better handling of path "/"

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Iterator;

public class FileSystemPath
{
    private static final String CLASSVERSION = "0.2";
    private ArrayList <String> pathAndFileArrayList;
    private String pathAndFile;
    private String firstDirectory;
    private String path;
    private int pathDepth = -1;
    private String filename;

    FileSystemPath( String pathAndFilename )
    {
        if( pathAndFilename == null )
        {
            throw new IllegalArgumentException( "ERROR: pathAndFilename cannot be null" );
        }
        if( pathAndFilename.isEmpty() )
        {
            throw new IllegalArgumentException( "ERROR: pathAndFilename cannot be empty" );
        }
        String sourceSplit[] = pathAndFilename.split( "/" );
        pathAndFileArrayList = new ArrayList <String>( Arrays.asList( sourceSplit ) );
        if( pathAndFileArrayList.size() == 0 )
        {
            throw new IllegalArgumentException( "ERROR: Filename cannot be empty" );
        }

        // TODO: untangle the initialization dependency chain below
        sanitizePathAndFilename();
        initializePathDepth();
        initializePathAndFile();
        initializeFirstDirectory();
        initializePath();
        initializeFilename();
    }

    private void sanitizePathAndFilename()
    {
        ArrayList <String> sanitized = new ArrayList <String>();
        for( String element : pathAndFileArrayList )
        {
            if( !element.isEmpty() )
            {
                sanitized.add( element );
            }
        }
        pathAndFileArrayList = sanitized;
    }

    private void initializePathDepth()
    {
        pathDepth = pathAndFileArrayList.size();
    }

    private void initializePathAndFile()
    {
        pathAndFile = join( pathAndFileArrayList , "/" );
    }

    private static String join( final Collection <String> s , final String delimiter )
    {
        StringBuffer buffer = new StringBuffer();
        Iterator <String> iter = s.iterator();
        while( iter.hasNext() )
        {
            buffer.append( iter.next() );
            if( iter.hasNext() )
            {
                buffer.append( delimiter );
            }
        }
        return buffer.toString();
    }

    private void initializeFirstDirectory()
    {
        int firstSlashLocation = pathAndFile.indexOf( '/' );
        if( firstSlashLocation == -1 ) // no slashes found means just the filename is left
        {
            firstDirectory = "";
        }else
        {
            firstDirectory = pathAndFile.substring( 0 , firstSlashLocation );
        }
    }

    private void initializePath()
    {
        int lastSlashLocation = pathAndFile.lastIndexOf( '/' );
        if( lastSlashLocation == -1 ) // no slashes found means just the filename is left
        {
            path = "";
        }else
        {
            path = pathAndFile.substring( 0 , lastSlashLocation );
        }
    }

    private void initializeFilename()
    {
        int lastSlashLocation = pathAndFile.lastIndexOf( '/' );
        if( lastSlashLocation == -1 ) // no slashes means just the filename was left
        {
            filename = pathAndFile;
        }else
        {
            filename = pathAndFile.substring( lastSlashLocation );
        }
    }

    protected String getVersion()
    {
        return CLASSVERSION;
    }

    protected String get()
    {
        return pathAndFile;
    }

    protected String getFirstDirectory()
    {
        return firstDirectory;
    }

    protected String getPath()
    {
        return path;
    }

    protected int getPathDepth()
    {
        return pathDepth;
    }

    protected String getFilename()
    {
        return filename;
    }

} // end class