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Chapter 1: Semeter 1, Week 1. Introduction to Computer Science Learn how to learn computer science A brief history of computing devices Counting in other numbers systems Primary memory and secondary memory devices Computer processors Computer hardware and peripheral devices What is programming? Program languages Computer operating systems like Windows, Unix, Mac OS Single user systems Networks Peer-to-peer networks LANs, WANS, Intranet, Internet Wired networks Wireless networks |
This first unit is very depended on the knowledge of incoming students. Most students should have received training in computer history and computer applications prior to enrolling in AP Computer Science. At the same time, the manner in which a computer stores information, processes information, the concept of programming and networks is usually not taught. A fun exercise with students is for the teacher to be a "robot" who follows a precise program of instructions to pick up chalk or marker and draw a circle on the board. It is even more fun with putting peanut butter on a slice of bread. Students quickly learn how much is assumed in human communication, which sets up the precision required for a computer program. Another exercise is to line up eight students, representing a byte. Each student is a bit with a place hold value. Students are "on" facing the class and "off" with their back turned. Use the student "byte" to represent base-10 numbers in binary memory. |
Evaluation: Chapter 1 Reading Quiz |
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Chapter 2:Sem 1, Week 2, Introduction to Programming in Java Getting started with Java Platform dependent and platform independent languages The Java bytecode concept Java application programs and applet programs Downloading and installing Java software Downloading and Installing an Integrated Development Environment (IDE) Responsible use of computer software, hardware Maintaining system reliability Hardware care Protection against surges and power outs Backing up data Protection against viruses and identity theft Intellectual property, copyright issues, shareware, freeware Social, ethical and legal implications of using computers Setting up the Java programming workspace Translators (Compilers and interpreters) The Java Virtual Machine (JVM) Compiling and executing Java applications and applets Java input/output issues Fundamental program text output with print and println Java compile errors | The main purpose of this unit is to teach students how to use the Java JDK and an IDE to write programs. The lab assignment involves literally copying a working program. The intent at this stage is to learn the mechanics of working with the software and clearly understanding the compiling and executing process. In particular students will learn the difference between compiler and interpreter translators. Once the different translators are clear, students then learn how Java uses both translators. The responsible use of the computer is taught throughout the year as good teachable moments arise. Unit 2 lends itself quite well for a good introduction. Students are shown how to download the Java software and JCreator. Both downloads are free and it is shown on the web site that the software is free. From this stepping stone of what is free, what is shared and what must be paid, the topic can expand into general issues of the ethical use of the computer. | Homework: Read Chapter 2 Evaluation:
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Chapter 3: Sem 1, Week 2-3, Java Primitive Data Types Declaring and operating with numerical simple/primitive data types Integer types (int, byte, short, long) Real number types (double, float) Arithmetic shortcut notations Limitations of finite representations Memory overflow resulting in imprecision Mathematical accuracy and computer accuracy Round-off errors and real number representations Other data types Character type (char) Boolean type (boolean) String type (String) Type casting Declaring constants with final Programs documentation Single line documentation Multiple line documentation Mathematical precedence in programs Escape sequences (\n, \\, \" \t \r) The AP Java subset importance The testing rationale and the subset need The importance for learning non-tested topics | Unit 3 is where students start to learn the concept of writing a program. At this stage all program writing is done in the main method. Students need to appreciate that the mathematical reality they have learned does not always apply to a computer. There are round-off errors, imprecise representations of floating point numbers and they need to understand what happens when a number is stored that is too large for its memory location. In this chapter students are first introduced to the notion that there is a course syllabus, which is a super set of the AP Computer Science topics that will be tested. With its first introduction String is not explained as a class with methods. The unique properties of the String data type allow it to be treated as a simple data type. After classes and methods are formally introduced in the next chapter, it will be easier to discuss the true nature of the String data type. The lab assignment helps to learn the difference between integer division and remainder division | Homework: Read Chapter 3 Do Practice Lab 3
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Chapter 4:Sem 1, Week 3-4, Using Methods and Parameters A brief history of program design OOP, a gentle first exposure Procedural abstraction Using the standard Math class Method abs, pow, sqrt, random Methods floor, ceil, round, max, min Fields PI, E Using methods of a user-defined class Accessing standard Java classes with packages using import Using methods with multiple parameters Compiling and executing applet programs Using the Graphics class of the java.awt package Methods drawLine, drawRect, drawOval The Color class: setColor method, color attributes Using the Java Class library to find information about a method and its parameters (arguments) |
Unit 4 introduces methods and parameters. This is hardly a complete unit on OOP. Students do learn some fundamental OOP terminology and realize the importance of using code that has already been written. In this case students use methods of several provided classes. Students will learn all the different OOP aspects during the course, but in this chapter the focus is to learn how to call methods of existing classes. The method calling is identical for standard Java classes or user-created classes. Graphics is intentionally introduced early. The use of graphics is optional in an AP course, and as such it is not tested. The reality is that students like graphics programs and are far more motivated to work on lab assignments with graphics output. There are other benefits. Calling graphics methods gives students excellent practice with methods that use many parameters. Another nice benefit of a graphics lab assignment is that it reinforces the concepts of Coordinate Geometry that they have learned in math classes. | Homework: Read Chapter 4 Practice Lab 4 Evaluation:
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Sem 1 Week 5 Control Structures I Types of control structures Simple sequence Selection Iteration Relational operators Keyboard program input with the Scanner class and System.in Selection constructs One-way selection with if Two-way selection with if...else Multiple-way selection with switch...case...break Iteration constructs Fixed iteration with for Pre-condition iteration with while Post-condition iteration with do..while Performing a variable trace Output exercises Control structures and graphics |
Unit 5 is intentionally called Control Structures I. The intention is to introduce Object Oriented Programming early in the course. The next four chapters will be devoted to various OOP concepts. However, a fundamental understanding of control structures will make the creating of classes and methods far more interesting. In this unit all control structures use single conditions. Unit 10 teaches students Boolean logic. Immediately following the Boolean logic chapter, students return to control structures and learn to use nested structures and compound conditions. The optional Scanner class is introduced in this chapter to provide an easy mechanism for entering keyboard input. Testing border cases with control structures is simpler when there is keyboard input available. The lab assignment continues the graphics theme started in unit 4. Students use control structures to draw hundreds of straight lines. The end result is an interesting graphics design. This unit also introduces students to variable tracing. Worked out exercises are provided for students to teach them to "play computer" and learn how to determine program output without using a computer. |
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Objective Quizzes/Exercises Lab Assignment: Curved Straight Lines Write a program that draws multiple straight lines in a pattern that displays curves. M.C. Chapter test |
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Sem 1 Week 6 And Week 7 Using Object Methods Classes and objects Calling the constructor method with new Calling object methods Overloaded constructors Using the Random class Methods nextInt, nextDouble, setSeed Using the DecimalFormat class Method format Using the Graphics class The hidden new operator of the Graphics object Additional Graphics methods setColor, drawPolygon, fillPolygon Using the Polygon class Method addPoint Constructing custom Color objects Anonymous objects Displaying random graphics objects with random colors Using the Scanner class Methods nextLine, nextInt, nextDouble Clearing the buffer with a dummy String variable Students are intentionally taught class methods first. With class methods the fundamental syntax of calling a method and using parameter is taught without the need to create an object with new. |
Unit six teaches students to use many classed that use object methods. It is now necessary to define an object and call the Class constructor with the new operator. This unit teaches that methods of the Graphics class are called with a Graphics object that appears to exist without the use of the new operator. This is an illusion, because the Graphics object is constructed in the background and then passed to the Graphics object parameter of the paint method. The Scanner class is now looked at closely with its three methods for string input, whole number input and real number input. Students also need to learn that bizarre things can happen when the buffer is not cleared after an input with nextInt or nextDouble. |
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Objective quizzes/exercises Lab Assignment: Write a program that displays random lines, random squares and random ovals with random colors. M.C. Chapter test |
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7 7 Sem 1 Week 8 And Week 9 Creating Class Methods The Math class revisited Modular Programming and user-created methods User-created parameter methods Actual and formal parameters Parameter passing rules Void methods and return methods Making a utility library class Introduction to program design with the Payroll class case study Program input with GUI Windows |
Unit seven teaches students many new concepts. Up to now students have learned to use both class methods and object methods. However, little program design is possible until students learn how to create their own classes and methods. The chapter starts with the idea of modular programming and the syntax required to create your own classes and methods. Students learn only to create classes with static or class methods. This allows an easier introduction that does not require creating constructors. The Payroll case study presents a very, very poorly designed program where every confusing program statement is shoved into the main method. The case study then demonstrates step-by-step how to improve the poorly designed program. This case is not yet a good example of Object Oriented Programming. It is a good start to teach important programming concepts. As additional concepts are taught so will additionally features of program design get introduced. This unit introduces the new "write-a-method" quiz style of evaluation. This style of quiz will steadily increase in quantity and help prepare students for the free response section of the AP Computer Science Examination. |
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Objective exercises Objective quiz and free response quiz Quizzes/Exercises Rewrite The Bad Program Lab Assignment: Take a provided, very poorly, designed program and rewrite the program with separate classes and methods. M .C. Chapter test |
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8 8 Sem 1 Week 10 And Week 11 Creating Classes with Object Methods Object method syntax Constructor methods Program reliability issues, like side effects Using encapsulation to increase reliability with private and public access Get return object methods Set modifying void object methods The CardDeck case study The Bank class revisited The Cube Case study Do you understand methods and parameters? |
The main focus of this chapter is for students to learn the importance of encapsulation. They have learned in prior chapter how to break up program code and place this code in modules. They have also learned how to declare parameters and make a distinction between void methods and return methods. However, they have only worked with static methods. In this chapter the issue of program reliability is addressed and students learn that first, and foremost, Object Oriented Design exists for the purpose of program reliability. Unit eight teaches students the importance of class member access in a proper manner by making a distinction between private and public access. The importance of understanding encapsulation is reinforced by three case studies. Each case study starts from a very simple program and slowly works itself to a complete program with properly designed encapsulation. The first case study features a PiggyBank class. The second case study designs a CardDeck class. The second case study intentionally is presented as if the first case study was never taught or understood. This approach with repeated reinforcement using different examples has proven very effective with students who are very overwhelmed by Object Oriented Programming. |
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Objective exercises Objective quiz and free response quiz The chapter finishes with 25 programs that make mistakes with using methods and parameters. For each program students need to identify the problem and offer a solution. Lab Assignment: The Rational Class Write a program that performs arithmetic operations with rational numbers. A rational number can be represented as a/b where a and b are integers and b is non-zero. A Rational class needs to be designed and implemented so as to perform each one of the binary operations. Additionally, the Rational class needs a computeGFC method that will be used to represent the final fraction in reduced format. M.C. Chapter test |
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9 Sem 1 Week 12 And Week 13 Inheritance and Composition Class specifications and relationships The "Is-a" inheritance relationship The "has-a" composition relationship Inheritance Inheritance syntax with extends Super classes and sub classes hierarchy Passing information to super class constructors with super private, protected and public access with inheritance Multi-level inheritance Can sub classes inherit from multiple super classes? Composition Inheritance syntax Handling constructors with composition Multi-level or multi-nested composition Can classes contain multiple classes? The JackO'lantern case study The Train case study The Object class |
Unit nine continues the Object Oriented Program introduction with a chapter on inheritance and composition. Students start by learning to make the distinction between inheritance and composition using many examples in real life that are "is-a" and "has-a" relationships. These are examples like a square is-a rectangle and a car has-an engine. Considerable time is devoted to the manner in which information is passed to a constructor in multi-level designs for both inheritance and composition. There are many composition examples and many students struggle much more with composition and than inheritance. In particular students need to understand clearly how to call and instantiate a constructor of a class that is nested inside another class. Two graphical case studies are presented to the students. Graphics is effective for students with many topics, but inheritance/composition topics especially benefit from the visual relationships. This chapter presents the first "open-ended" lab assignment. This is somewhat scary to students, but it is a very important technique to start getting students thinking about how programs are designed. Additionally, the assignment is also done with small teams to simulate the real-life experience of completing projects with more than one person. |
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Objective exercises Objective quiz and free response quiz Lab Assignment: Open Ended Inheritance/Composition Graphics Program Write a graphics program that displays both inheritance and composition. The program is open-ended, because there is no required output shown. The program needs to be in the style of the JackO'lantern which is-a pumpkin and has-a face. This lab assignment is done with three or four students working together as a team. M.C. Chapter test |
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10 Sem 1 Week 14 Boolean Logic A brief history of Boolean Algebra George Boole The birth of Boolean Algebra The significance of Boolean Algebra to computers Boolean statements Boolean operators and (&&), or (||) and not (!) Truth tables Laws of Boolean Algebra Common Boolean Algebra laws Special focus on DeMorgan's law Venn diagrams and Boolean Algebra Representing and as intersection Representing or as union Sample Boolean problems The boolean data type Boolean logic exercises |
Most computer science text books include Boolean logic in chapters where conditional statements are introduced. An Educational Testing Service (ETS) study performed in the early Nineties showed that students who performed quite poorly on Boolean Algebra questions, tended to perform poorly overall on the AP Examination. This chapter is intentionally placed between the Control Structures I and the next Control Structures II chapters. Students can learn about Boolean logic without being concerned with writing any type of programs. With the exception of the few program examples that demonstrate the boolean type, the chapter is completely language independent. The laws of Boolean Algebra are not presented with the intention to learn the name of each law, with the exception of DeMorgan's Law. Each law can be presented in an investigative, intuitive manner. Students can apply the proper Boolean logic to a problem without actually knowing the name of the law that is being used. The chapter finishes with a set of Boolean Logic exercises to test understanding of the chapter before students take a chapter test. |
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Objective Quizzes/Exercises M.C. Chapter test |
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11 11 Sem 1 Week 15 And Week 16 Control Structures II The for loop revisited Which is the best loop to use? Nested selection structures Nested looping structures Compound conditions Program input protection Common logic errors Using DeMorgan's Law properly Short-circuiting compound conditions Recursion, a sneak preview Output exercises |
Unit eleven introduces students to programs that involve considerable complexity. In the real world conditional statements are rarely simple. They tend to be compound. In the real world there also needs to be input protection against erroneous data entry. This chapter addresses these issues. The chapter also introduces recursion very briefly as a means to control program execution sequence. It is meant to set the stage for a future chapter. This chapter also presents a set of output exercises to test knowledge of variable tracing. The program assignment is a large program (Students certainly think so) involving formulas and control structures that are used to compute interests and payments. This assignment is so much more than simply an application of compound conditions and nested looping. Few students, and often adults, truly understand the nature of interest. This lab assignment demonstrates the size of the monthly payment that is made for various loans. It shows how incredibly long it can take to pay off a credit card when the minimum payment is made. Students are often quite amazed when they run their programs and see that on many credit card scenarios they will not live long enough to reduce the balance to zero by making minimum payments only. |
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Objective exercises Objective quiz and free response quiz Lab Assignment: Watch What You Borrow Program Write a program that enters information pertaining to loan/credit card balances, interest rates and payback time. The program then computes the amount of a monthly payment, an amortization schedule, a credit card payoff and also displays the total payments and total interest paid. M.C. Chapter test |
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12 Sem 1 Week 17 And Week 18 Java Static Arrays Data structures in general Static array definition Declaring a one-dimensional array Traversing an array With a loop structure using index access and the length field With the enhanced for..each loop structure Placing an array as a private attribute in a class The user-created List case study I Using the Arrays class Displaying array elements with Arrays.toString Storing identical array elements with Arrays.fill Sorting array elements with Arrays.sort Searching for an array element with Arrays.binarySearch Potential problems with using a binary search Input at the command prompt into the main method args array Executing a program with command line input Accessing args array values Converting input with Integer.parseInt and Double.parseDouble Static Imports Package requirements to use static imports Static import examples with System, Math and Arrays |
Chapter 12 introduces the Java static array. This array does involve the creating of objects with the new operator, but students quickly learn that these arrays do not behave like classes. There is no constructor call and there are no methods. Students need to learn that length is a final field and not a method. Using an array, static or otherwise, inside the main method is poor Object Oriented Design. The List case study places the array data structure inside a class and performs fundamental access procedures. Sorting and searching methods will be shown in a later Algorithm unit. Students do learn about sorting and searching at an abstract level. They will use Java's Arrays class to perform various array processing, including sorting and searching. In this unit students will finally understand the meaning of the main method parameter list by learning how to enter values at the command prompt that will be stored in the args array variable. The chapter finishes by importing static packages that allow access to the static methods of classes like, System, Math and Arrays without using class identifier. |
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Objective Quizzes/Exercises Lab Assignment: Sieve of Erasthenes and Graphics Sorting Write a program that computes prime number using the "Sieve of Erasthenes." Write a program that generates random rectangles, which are displayed on half the screen. The bottom part of the screen shows the same rectangles sorted in ascending order. M.C. Chapter test |
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13 13 Sem 2 Week 1 Advanced Graphics Review of basic awt graphics Methods drawLine, drawRect, fillRect, drawOval, fillOval, drawArc, fillArc, setColor, drawPolygon, fillPolygon Controlling graphics text with drawString and setFont Mathematics and graphics Drawing circles and regular polygons with Math.cos and Math.sin Using x and y coordinate arrays with the Polygon class Using mouse interaction with graphics The event method concept Methods mouseDown, mouseEnter, mouseExit, mouseMove, mouseUp, mouseDrag Creating graphics animation Fundamental draw-and-erase animation Virtual memory and video buffering Reserving virtual memory with Image and getGraphics Page flipping with drawImage Improving animation flicker with the update method |
Unit thirteen is an example of a chapter that is totally optional from the point of view of AP Computer Science topics. Yet the benefits of this topic are so great that inclusion will benefit any strong AP Computer Science course. Every aspect of graphics programming reinforces computer science topics. Students enjoy graphics and they easily write far greater programs with enthusiasm than they would with a typical text-output program. As programs become larger considerations of program reliability become an important issue, which turn motivates proper program design. Debugging and enhancing a large program is also far more challenging and many computer science concepts that often make little sense with small program examples now become crystal clear. For example, consider a student who needs to display 144 buttons on a screen for a mine-sweeper game. Initially, the student may write 15 lines of code for the display of each button. This becomes an unwieldy amount of code in a paint method. The need for a button method along with a separate class that includes the drawButton method and other actions motivates thinking about program design. |
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There are no exercises/quizzes Lab Assignment: Paint Program Write a program that performs the fundamental functions shown by the Windows Paint program. The assignment is open-ended in the sense that a precise display is not required. Students are expected to create their own graphical interface. The assignment is scored on the number of Paint features that are shown. There is no chapter test |
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14 14 Sem 2 Week 2 and Week 3 Serious OOP OOP terminology Modules, Structured Programming, OOP Definition, Encapsulation, Instantiation, Inheritance, Polymorphism, Class, Object, Instance, Attributes, Instance Variables, Methods Default, no-parameter constructors Constructor overloading Accessing attributes and methods private access public access Accessing multiple files and classes Get methods and Set methods Copy constructors Scope of an object Objects are references All parameters are passed by value Primitive actual parameter values can never be altered Object actual parameter attributes can be altered Using the "this" reference Mixing class methods and object methods |
Unit fourteen is very important. Teaching computer science suffers from trying to talk seriously about a topic when students have insufficient knowledge to appreciate all the good points teachers try to make. Object Oriented Programming has been introduced since early in the course. There have been many chapters where different OOP topics have been emphasized. This chapter once again discusses many OOP topics, starting with a lot of the OOP vocabulary. Keep in mind that this chapter is not strictly a review of rehashing previous topics. As old topics are reviewed they then continue and include a more thorough look at the technical details. One of the most important concepts that students need to clearly understand at this time is the idea that all objects are references and that parameters are all passed by value. Understanding these two related topics allows students to design correct methods that alter values as intended without side effects caused by unwanted aliasing. The chapter finishes with some examples of how and why you may want to mix class methods and object methods. This may not be tested directly, but this concept gives a deeper understanding of class methods and object methods. |
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Objective Quizzes/Exercises Lab Assignment: The FishGfx Program For Lab14a write a program that uses a provided FishGfx class to manipulate the movement of fish. For Lab14b write an implementation of a FishGfx class. M.C. Chapter Test |
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15 15 Sem 2 Week 4 Working with Large Programs and Object Oriented Design Simple projects Complex projects with JAR files Advanced Java comments with Javadoc Timeless Design Issues Read and understand a problem description, purpose and goals Program documentation Self-documenting identifiers Program comments Modular programming Functional Decomposition (Top-down design & step-wise refinements) Testing and Debugging Compile, runtime and logic errors Common Java exceptions Practical debugging techniques Object Oriented Design Identify appropriate classes Using existing classes Creating new classes Class design and implementation Establishing a class hierarchy with inheritance and composition Method design with pre-assertions and post-assertions Java program writing code conventions |
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Free response exercises and quizzes Lab Assignment: The Design Program Design a program based on provided specifications. The program requires classes and method stubs. Method implementations are not required. M.C. Chapter Test |
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16 Sem 2 Week 5 String Processing and Number Systems Constructing different String objects String concatenation Working with substrings Changing immutable String objects Converting String objects Comparing String objects Counting in other number systems Counting in base-16 Converting from base-x to base-10 Converting from base-10 to base-x Converting between base-2 and base-16 |
String processing an important computer science topic. This chapter includes all the required AP Java subset String methods and a few extra methods. The number systems topic is intentionally added to this chapter. Number system conversion is an AP Computer Science topic and can be handled as a stand-alone unit. Any number system conversion between base-16 and other bases involves the processing of numbers and letters, in short it involves string processing. The lab assignment at the end of this unit combines the two, apparently unrelated, topics. Students need to write a program that converts number between any two bases. This assignment requires a clear understanding of number system conversion and continues with an understanding of string processing to implement the program assignment. |
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Objective exercises Objective quizzes and free response quizzes Lab AssignmentL Number System Conversion Write a program that converts a number from any base into any other base M.C. Chapter Test |
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17 17 Sem 2 Week 6 Input/Output with Sequential Files Different types of files Sequential access files Random access files Using the File class Determine file existence Determine file properties Input text files with BufferedReader and FileReader Wrapper class concept with anonymous objects File buffer concept Output text files with BufferedWriter and FileWriter Handling text files with integer and double values Storing numerical values in a text file Converting numerical strings into int and double values A note about the Scanner class and file handling |
The entire file unit is optional from an AP Computer Science Examination point of view. On the other hand, files handling is extremely important. Any student who receives college credit and continues computer science in college will be expected to have at least an elementary file-handling understanding. The Collegeboard has decided not to test file handling with the Java language due to the tremendous number of classes that are available for this concept. However, the importance of this topic is expressed in the course description even if it is not tested. All the file handling in this unit is done with a minimum of classes and only with text files. Numerical files are still treated as text files and then converted where necessary. Students have already used the Scanner class for keyboard input. It is possible to use the Scanner class for file input as well. However, this creates an odd symmetry between file input and file output. Students also learn the file buffer concept better by using two file handling objects wrapped around each other. This approach has proven to provide a deeper understanding of file processing. |
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Free response exercises Free response quizzes Lab Assignment: The Student Records Program Write a program that reads in and manipulates student data. M.C. Chapter test |
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18 18 Sem 2 Week 7 Algorithms I and Informal Algorithmic Analysis The user-created List class case study Improving input and output The linear search The bubble sort Array insertion and deletion The selection sort The binary search Sorting an array of records The merge sort concept Select appropriate data and algorithms Testing algorithms with the user-created TimeTest class Informal comparisons of algorithm running times Exact calculation of execution counts |
Students continue to build the List case study that was started in the earlier static array chapter. In this chapter the sorting and searching algorithms are now implemented. The Bubble Sort is intentionally taught first. It is a very simple sort to teach and it is an excellent stepping stone for informal algorithmic analysis. Students learn to identify algorithmic weakness and explore improvements. For instance, the Bubble Sorts is continuously swapping during each comparison pass. If the swapping is postponed until the end of the comparison pass, then there is only one swap routine required and this motivates the Selection Sort. Students observe the comparison between different algorithms by using a TimeTest class. This user-created class provides a convenient method to display elapsed time. Students are not expected to calculate analysis with formal Big-O notation, but they can informally observe and discuss the behavior of algorithms. Students also learn to perform exact execution counts. The student record program, started in Unit 17, is continued. Convenient file access reads in all the records, which can now be processed for sorting and searching. |
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Free response exercises Free response quizzes Lab Assignment: The Student Records Program Write a program that continues the Lab17 assignment and now includes the sorting and searching of student information using static Java arrays in a List class. M.C. Chapter test |
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19 19 Sem 2 Week 8 And Week 9 Recursion I Recursion definition Recursion requires an exit with a "base" case Recursion fundamental rules Recursive void method examples Recursive return method examples Fibonacci, an inefficient recursive solution Evaluating recursive methods Manipulating parameters of recursive methods Multiple recursive calls and the "Tower of Hanoi" Why recursion? |
Recursion is frequently shortchanged in the first computer science course. "A-Level" students are not expected to implement recursive methods in the manner of binary tree methods like the "AB-Level" exam. However, students need to have a clear understanding of the recursive process and need to know how to evaluate recursive methods. This chapter has extensive exercises and quizzes to give students practice in evaluating recursive methods. This unit has two lab assignments. The first assignment involves rewriting existing iterative methods into recursive methods. The second assignment requires writing a fractal program. Many fractal programs involve sophisticated mathematics, such as complex numbers. The square fractal focuses completely on the recursive process. |
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Objective and free response exercises Objective and free response quizzes Lab Assignment: The Recursive Method Program and The Square Fractal Program Complete a program, which contains seven iterative methods and rewrite the method recursively. Write a program that displays a square fractal. M.C. Chapter test |
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20 Sem 2 Week 10 The ArrayList Class and Redefining Methods Declaring the ArrayList class ArrayList methods Handling ArrayList objects with class casting Handling ArrayList objects with a "templated class" declaration Accessing an ArrayList of records Redefining Methods The Object class Redefining the toString method Redefining the equals method Autoboxing Automatically wrapping a primitive data value into an object Automatically "unwrapping" an object into a primitive data value Generics Declaring an ArrayList object with specific class elements Combining autoboxing and generics with ArrayList objects |
Students need to see a comparisons between Java static arrays and the ArrayList class to appreciate the need to learn both array implementations. Using ArrayList methods is quite simple for students. Processing objects nested with multiple levels inside other objects is quite complex. The program assignment intentionally returns to the, by now familiar, Student Records program. This program has multiple levels of composition and teaches students precisely at which level various ArrayList objects and other objects need to be instantiated. The ArrayList class also motivates the concept of redefining and implementing methods. Static java arrays require a loop structure to display individual elements. ArrayList objects simply display all the elements with a print method call. It is at this point that the true nature of the toString method and other methods like equals can be explained for maximum understanding. The ArrayList chapter is a convenient location to introduce the new autoboxing and generics features found in Java 5.0. When both autoboxing and generics are combined, ArrayList processing with primitive data types becomes much simpler. |
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Objective and free response exercises Objective and free response quizzes Lab Assignment: The Student Records Program Repeats the Lab18 program, but now use ArrayList objects M.C. Chapter test |
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21 21 Sem 2 Week 11 and Week 12 Interfaces, Abstract Classes and Polymorphism Classes and interfaces Implementing interfaces Implementing existing interfaces like Comparable Implementing user-created interface Implementing multiple interfaces Using fields in an interface Abstract classes Polymorphism The Object class and polymorphism |
Students first learn the difference between classes and interfaces and then learn how to implement interfaces. This unit also continues the concept of redefinition shown in the last chapter with toString and equals. This time method compareTo is defined; although not exactly redefined, but implemented. The chapter concludes with an explanation of the usefulness of interfaces and abstract classes. At this point students learn about polymorphism. Polymorphism shares a problem with recursion. Too frequent the topic is viewed as an "AB-Level" topic. This is only true in the implementation sense. At the "A-Level" students are expected to understand the concepts of interfaces and abstract classes. |
Evaluation:
Objective and free response exercises Objective and free response quizzes Lab Assignment There is no lab assignment meant specifically for this chapter, because students will immediately do a major unit with many labs for the MBCS, which uses interfaces and polymorphism. M.C. Chapter test |
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22 22 Sem 2 Week 13, 14 And Week 15 The Marine Biology Case Study and Preparing for the AP Exam Why is there a case study on the AP Computer Science Examination What is the Marine Biology Case Study? Compiling and executing the MBCS Understanding the classes and methods of the MBCS Altering existing MBCS methods Creating new MBCS methods The AP Computer Science Examination format The significance of the AP Java subset The AP Java standard libraries How the MBCS is tested Sample multiple choice questions Sample free response questions The grading of the response questions Exam day important reminders |
At this stage the end of the course is rapidly approaching. Students must realize that the AP Exam is not at the end of the school year, but the first week in May. Students will work through a very concentrated three-week unit on the Marine Biology Case-Study. work with the MBCS is not simply included, because it is on the test. Students will get an excellent review of all computer science topics during this unit. The case evolves during the three-weeks where students start by observing the program execution, continue with investigation of the core classes and supporting classes. After students have gained more understanding, they will then start to make small changes to existing methods. Near the end of the unit students will implement new methods and make major changes to the program. The last chapter includes a thorough preparation for the AP Computer Science Examination. Students have already learned all the knowledge to take the examination. This final review makes them totally familiar with the exam format and warns students about the grading process to maximize their performance. |
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Objective and free response exercises Objective and free response quizzes Lab Assignments: There are extensive lab assignments for the MBCS. At the "A-level" there are eight labs starting with compiling the MBCS and steadily evolving by altering existing methods and fish behavior and then writing a "Shark" method, which is a predator fish. M.C. Chapter test |