CSC153, Class 47: Linked Lists

Overview:
* Deletion in array-based lists
* Packages in Java
* Implementing Scheme-like lists
  + The Node class
* Variations

Notes:
* Lots of housework last night.  No grading of exam.
  No grading of homework.  No class prep.  Bleh.
* No more homework in CSC153.  Horray!
* Math/CS Picnic, Friday, 2 May 2003 (optional).
  Be there and be square.

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Packages in Java

A package is a group of classes that naturally work together.

Why have packages?
* Modularity
* Protection: We may want to make components of an object
  available only to other objects in the same package.

Naming strategy for packages

Traditionally "reverse domain" + "project" 

edu.grinnell.cs.csc153.2003S.lists

For now, we'll use the simpler "project" name

linkedlists

You need to make a directory (or hierarchy of directories)
for your package

Each class in the package must begin with 

package PACKAGENAME;

Compile above the top-level directory with

javac package/file.java

Packages are there to encourage good style, not to enforce it.

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Return to our study of lists in Scheme.  Recall that all lists
are built from pairs.  Each pair stores two things: a pointer
to a value and a poitner to the next thing.

A pair is really easy to implement in Java. 

Traditional programmers call these "Nodes".

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FOR NEXT TIME:

* Nicely chastise Katherine Gray for skipping class.
* Think about cursors in linked lists.