We show Click here for expected future lectures
Calendar (list of lectures, showing also prelims, some assignments)
PAST AND PENDING LECTURES AND LABS
Lecture 28. 08 May (Thursday). Conclusion. Don't miss it!
CS history and other things pdf ppt
Lab 13. No assigned lab. The Lab TAs and consultants will be in the lab to answer questions about A7 and the final.
Lecture 27. 04 May (Tuesday). OO programming.
We discuss the idea of OO programming and how one decides on the classes to design and imlpement. We also develop loops or recursive functions in preparation for the final. And we will touch briefly on interfaces. pdf ppt showboat.zip (the java demo)
Lecture 26. 28 April (Thursday). Interfaces. An interface is like an abstract class in which all methods are abstract. A class may extend only one other class, but it can "implement" several interfaces. We show how this feature can be used effectively. pdf ppt
Lab 13. Exception handling. This lab asks you to study and write code that uses exceptions, throw clauses, try-statements, etc. It's best if you read the chapter on exception handling first. pdf doc Lab13.java
Lecture 25. 26 April (Tuesday). Applications
A stand-alone Java program —one that can be executed outside of DrJava— is either an "application" or an "applet". An application can be executed from a command line in a "terminal" or "DOS" window, or one can double-click on them to start it. Applets are started when an html web page contains the proper "applet tag". We show you how to make a Java program into an application and into an applet, we show you how to create a jar file that contains an application or an applet, and we also look at the language html, which is used to construct web pages. pdf ppt zip file containing demos
Lecture 24. 21 April (Thursday). Ragged arrays. We show how Java treats a two-dimensional array: as one-dimensional array whose elements are one-dimensional arrays. This allows us to have an array whose rows have different lengths, giving u "ragged" array. pdf ppt
Lab 12. Formatting in locales. A "locale" is a country together with a language used in that country. This lab gives you experience with class Locale, instances of which give you functions that format numbers, percentages, and currencies in the way that those locales use. For Americans, this can be an eye-opener! pdf html JLiveWindow.java MyJLiveWindow.java
Lecture 23. 19 April (Tuesday). Exceptions. An "Exception" is an "untoward" event like division by 0 or a subscript out of range. Java has a nice facility for handling and recovering from Exceptions. pdf ppt Ex.java OurException.java Reader.java
Lecture 22. 14 April (Thursday). Listening
We show how to listen to mouse clicks on buttons, mouse clicks in on components, and keystrokes.
pdf ppt javaFilesUsedInClass (zip file) and other examples of gui-listeners: See Chapter 17 of the CD ProgramLive.
Lab 11. Timing execution. We show you how to time execution of a method call and ask you to compare times for various searching and sorting methods. pdf doc Sorting.java TestArrays.javaLecture 21. 12 April (Tuesday). Placing components in GUIs.
Lecture 20. 07 April (Thursday). Finding an invariant: important algorithms.
We continue our study of developing algorithms that process arrays. No new slides for this lecture. See handouts for last two lectures.
Lab 10. Exercises with loops. This lab asks you to develop loops from specifications and given invariants, giving you practice with the methdology for developing loops. pdf doc
Lecture 19. 05 April (Tuesday). Finding
an invariant: important algorithms.
We develop the binary search, linear search, and some sorting algrithms. Sorting.java contains all the searching/sorting methods we use in this class. Download it. pdf ppt Sorting.java
Lecture 18. 31 March (Thursday). Assignment 6 and debugging.
We discuss assignment A6, Images. We then talk about debugging. The powerpoint slides do not show everything we did because we concentrate on finding errors using DrJava. You can look at the lecture at www.videonote.com/cornell. pdf ppt
Lab 09. Reading (and writing) files. We show you how to read a file that is on your hard drive. Reading a keyboard and writing as file is just as easy. pdf html Download lab09.zip or Lab09.java, cms.txt, peop.txt
Lecture 17. 29 March (Tuesday). Finding
an invariant: important algorithms.
We look at how to combine diagrams for pre- and post-conditions of an algorithm into an invariant for a loop and use it to develop some interesting algorithms that have loops. pdf ppt
Lecture 16. 17 March (Thursday). Arrays.
We introduce arrays. An array, like Vector, is an object that can contain a list of things. A variable of type int contains the name of an object that contains a list of ints. A variable of type JFrame contains the name of an object that contains a list of JFrame objects. Type array is built into Java; there is a nice mathematical notation b[i] for accessing element i of array b. We consider right and wrong methods for swapping values of array entries. pdf ppt
File D.java contains the methods we developed in lecture. It also contains the function to roll a die with a apoosible unfair die as well as a procedure that can be used to test it, rolling the die as many times you want and tabulating the results. Take a look!
Lab 08. For-loops and assertions. This lab deals with some paper-and-pencil exercises on ranges, assertions, and for-loops. It also asks you to write four functions whose bodies contain for-loops. pdf doc Lab08.java
Lecture 15. 15 March (Tuesday). The while loop.
We introduce the while loop, relate it to the for-loop, talk about the four loopy questions for understanding a while loop, and develop some while loops. pdf ppt D.java Wrap2.java
Lecture 14. 10 March (Thursday). More on loops.
We continue with the discussion of developing for-loops that process a range of integers, using postconditions and invariants. pdf ppt GrislySnowflakes
Lab 07. Abstract classes and methods. We introduce the notions of abstract classes and methods and state why they are useful. The example program you will play with gives you practice with them. pdf html DemoShapes.java Shape.java Parallelogram.java Rhombus.java Square.java
Lecture 13. 08 March (Tuesday). Loops
We begin a discussion of loops, starting with a for-loop to process a range of integers. pdf ppt
Lecture 12. 03 March (Thursday). Drawing and casting about. We work on further issues with classes and subclasses that arise from the distinction between apparent and real classes, and examine the use of casting and instanceof in these contexts. pdf ppt
Lab 06. Recursion. You will write at least 4 recursive functions. pdf html Rec.java
Lecture 11. 01 March (Tuesday). More recursion
We develop a few more recursive procedures, including Hilbert's space-filling curve. We execute some recursive calls. As we figure out how many recursive calls one function makes, we will have to discuss the binary number system. pdf ppt 11mar01demo.zip This file contains (1) Class D, which contains the recursive functions written during this lecture; (2) class PairDI.
Lecture 10. 25 February (Thursday). Recursion!
We introduce recursion: a method calling itself. This provides power and flexibility that we haven't had yet, and you will (should) be amazed at how simple it will be to do neat things. pdf ppt D.java (contains functions we wrote in class)
Lab 05. Class Vector. An instance of class Vector can contain a list of objects, and the list can expand and shrink. In this lab, we study this class. It will be used in a lot of our future work. pdf html Lab05.java
Lecture 09. 23 February (Tuesday). Wrapper classes, class Vector, and more stepwise refinement.
Each primitive type has an associated "wrapper class". An object of the wrapper class contains one value of the primitive type. We show you why this is useful. We also spend more time developing algorithms dealing with Strings, showing you "top-down programming" and "stepwise refinement" in the context of a real java program. pdf ppt Course.java DeptLink.java
Lecture 08. 17 February (Thursday). Odds and ends
on classes. Stepwise refinement
We make some points about multiple constructors, overriding, and constructors in subclasses. We then develop some more String functions and talk about stepwise refinement. pdf ppt two classes for anglicization functions: Anglicize.java AnglicizeTester.java The Knack
Lab 04. Writing functions. You will practice writing functions that deal with Strings. Please study the first part of the lab, on Strings and string equality, BEFORE Tuesday, so that you don't have to waste time in lab. This will help also in understanding Tuesday's lecture. An important point should become clear: a value of String is an object , so a test s == t where s and t are Strings tests whether they are the same folder or not. Method call s.equals(t) should be used to test whether two Strings have the same value. pdf docx Methods.java The Knack
Lecture 07. 15 February (Tuesday). Inside-out, super-this,
and stepwise refinement
We illustrate the inside-out rule for referencing variables and methods, which is used in most programming languages. We discuss this and super. The main topic is stepwise refinement --a way to think about the development of methods from their specifications-- and develop an interesting function using it. pdf ppt two classes for anglicization functions: Ang.java AngTester.java
Lecture 06. 10 February (Thursday). Methods
We look more closely at how a method call is executed. We show the four steps involved in executing a method call. We introduce local variables. We now have four kinds of variable: parameter, static variable, field, and local variable. You should know where and how each is declared and what its scope is. We introduce conditional statements and return statements. pdf ppt
Lab 03. Two topics: testing and static variables. You will practice creating a test class to test and help find bugs in a class that we give you. Also, we give you some things to do to make clear to you when methods can be made static. pdf html ThreeDimPoint.java
Lecture 05. 08 February (Tuesday). Testing; the class hierarchy;
static variables and methods.
We discuss testing, including with JUnit. We talk about the class hierarchy and show you the superest class of them all: Object. We discuss function toString. We introduce static variables and methods. pdf ppt Worker.java WorkerTester.java
Lecture 04. 3 February (Thursday). Customizing a
class: getters, setters, constructors
We discuss fields and getter and setter methods for them. We introduce constructors, whose purpose is to initialize (some) fields of a newly created object pdf ppt Worker.java WorkerTester.java Gremlin.java
Lab 02. Objects and classes. You will practice creating and manipulating JFrame objects using DrJava's interactions pane. Then, you will write your first class definition —a subclass of JFrame, and experiment with it. pdf html
Lecture 03. 01 February (Tuesday). Customizing a class
We introduce the class definition, which describes the format of all manila folders (object, instances) of a class. We illustrate using a "subclass" of JFrame customized to our needs. We show how to create a class"specification" using the javadoc facility. pdf ppt
Here is Richard Felder's website on learning styles: www4.ncsu.edu/unity/lockers/users/f/felder/public/Learning_Styles.html
Lecture 02. 27 January (Thursday). We define what an object (manilla folder) is and demo the creation and manipulation of objects in DrJava. This material, in Sect. 1.3 of the text, is the basis for the next lecture, so study the material and practice using DrJava. Look at the self-study exercises in the text and do some of them. The more you practice, the easier it will seem. pdf ppt
Lab 01. Java expressions. This lab involves practice with Java expressions and assignments using the DrJava Interactions pane. pdf html
Lecture 01. 25 January (Tuesday). Introduction to the course --brief overview of what we missed last Thursday. Discussion of Java types, expressions, variable declarations, and assignment statements. Lecture handout: pdf ppt
FUTURE LECTURES AND LABS
The list of lectures and labs shown below are for Spring 2010. They will give you an idea of where we are headed in the Springl 2010 course. The links given below will not work.
Lecture ?. ?? (Thursday). Finding
an invariant: important algorithms.
We continue look at how to combine diagrams for pre- and post-conditions of an algorithm into an invariant for a loop. We develop insertion sort, selection sort, and the recursive quick sort. We give a historical perspective on programming. pdf powerpoint Sorting.java
Put this file spin.gif intoyour favorite browser and take the left-brain-right-brain test. This website discusses whether this spinning dancer tells you anything about your brain: scienceline.org/2007/10/29/ask-hsu-spinning-girl-right-left-brain-hemispheres/