LukasKorsikaDesignStudy

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== Initial Design ==
 
== Initial Design ==
 
''(converted to Java from C, so some liberties have been taken with classes, but this is essentially its original form)''
 
''(converted to Java from C, so some liberties have been taken with classes, but this is essentially its original form)''
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[[image:Lko15-OldUML.png]]
  
 
=== Design Description ===
 
=== Design Description ===
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I realise that this is terrible design. This design study will iteratively improve the design, as well as creating a Java implementation of the program.
 
I realise that this is terrible design. This design study will iteratively improve the design, as well as creating a Java implementation of the program.
 
[[image:Lko15-OldUML.png]]
 

Revision as of 03:38, 29 July 2010

Contents

The Problem

The project I design in this study is an application to help me manage my file system. I tend to have a number of copies of the same file scattered throughout my various file system for reasons such as:

  • Some partitions are only accessible under Linux
  • I often copy videos to my laptop to watch away from my desk.

Requirements

  • Must take a list of files as input, and output identical files in groups (ie, cluster all identical files together, don't output unique files)
  • Must support a variety of approaches for determining equality -- based on raw data, or file-type specific comparisons.
  • Must use reasonable amounts of memory and I/O bandwidth.
  • Should be file-system agnostic (and support NFS, etc)
  • Should be extensible

Initial Design

(converted to Java from C, so some liberties have been taken with classes, but this is essentially its original form)

Lko15-OldUML.png

Design Description

As this was a program in C, there is essentially a God Class, with a few helper classes and methods thereupon. The helper classes are:

  • File -- This represents a file on the file system, and has methods to find its size, and its SHA-1 hash.
  • Tree -- This is a simple class representing a Tree. A tree is composed of a set of TreeNode, and stores a reference to the root.
  • TreeNode -- A tree node represents a node in a binary tree, stores its key (which may be size or hash depending on the tree), and a list of all files which have that value. TreeNode has a number of recursive methods to iterate over the tree, get the list of files at that node, and insert a new file with a key recursively.

I realise that this is terrible design. This design study will iteratively improve the design, as well as creating a Java implementation of the program.

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