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IT 313 -- Examples

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HelloWorld Greeter InchesToCm TerminalIO ComputeAverage Loops Unicode Drawing StaticMethods InstanceMethods UnitTests Classes InputOutput Inheritance TestPackage JFreeChart Interfaces Serialization EmployeeFind PackageAccessibility Patterns1 Observer Patterns2 JDBC Swing Recursion Multithreading SwingGui KotlinProj

HelloWorld Project

Zipfile: hello-world.zip

This project has no modules defined.
Creating an IntelliJ HelloWorld Project

Print the message "Hello, World!" to standard out.
HelloWorld.java

Greeter Project

Zipfile: greeter.zip

This project has four modules defined.
Creating a Project with Multiple Modules

Module greeter1: Display a greeting to the person whose name is specified.
Main.java
Module greeter2: Same as the greeter1 module, but use the makeGreeting method to construct the greeting.
Main.java
Module greeter3: Same as the greeter2 module, but put the main method and the makeGreeting method in separate classes.
Main.java Greeter.java
Module greeter4: Instead of inputting from standard in and outputting to standard out, use an input dialog and a message dialog for input and output, respectively.
Greeter.java

InchesToCm Project

Zipfile: inches-to-cm.zip

Module in2cm1: Input a length in inches and convert it to centimeters.
Main.java
Module in2cm1: Input a length in inches and convert it centimeters. Use a method to perform the conversion.
Main.java
Module in3cm1: Input a length in inches and convert it centimeters. Use a method to perform the conversion, placing the method in a the separate source code file Convert.java. The method call must be qualified by the class where it is located.
Main.java Greeter.java

TerminalIO Project

Zipfile: terminal-io.zip

Module wordtonum: Input a one digit number in words, then output the corresponding integer.
Main.java
Module tipcalculator: Calculate the tip for a restaurant bill. Always tip at least one dollar.
Main.java
Module gradecalculator: Input class score, output course grade.
Main.java

ComputeAverage Project

Zipfile: compute-average.zip

Module ave1: Enter quiz scores as double values at the keyboard. Terminate list with 999.9. Output average of scores.
Average.java
Module ave2: Enter count of quiz scores. Then enter quiz scores as double values at the keyboard. Output average of scores.
Average.java
Module ave3: Enter quiz scores as double values at the keyboard. Terminate the list with Control-D. Output average of scores.
Average.java
Module ave4: Enter name and quiz score pairs separated by commas. Terminate the list with Control-D. Output average of scores.
Sample input list:
```
Alice,96
Bob,84
Chloe,98
Danny,100
^D
```
Average.java

Loops Project

Zipfile: loops.zip

Module counting: Count to 100 using while and for loops. Also count backwards from 100 to 1 by 7s.
Main.java
Module stats: Compute the count, sum, average, min, and max for a list input from the keyboard.
Main.java
Module dice1: Print NUM_ROLLS rolls of two fair dice; rand.nextInt(6) returns a random int in the interval [0,6) (0 inclusive, 6 exclusive).
Main.java
Module montecarlo: Estimate the value of π (pi) by generating random points (x, y) with x and y in [0.0, 1.0). The probability that (x, y) lies in the circle with center (0.5, 0.5) and radius 1.0 is π/4.
Main.java
Module hailstone: Given the start value n₀, generate the Hailstone sequence:
If n_i is even n_i+1 = n_i / 2, otherwise n_i+1 = 3 * n_i + 1.
The sequence is called a Hailstone sequence because its values move up and down in an unpredictable manner, similar to hailstones in a thunderstorm cloud. Mathematicians believe that all Hailstone sequences terminate with one, even though they have not been able to formally prove this for all starting values.
Main.java

Drawing Project

Zipfile: drawing.zip

Instantiate a MyFrame object derived from the Swing JFrame class. The MyFrame object contains a JPanel object that displays a Swing drawing using Graphics methods. No modules are defined for this project.
Main.java MyFrame.java MyPanel.java

Unicode Project

Zipfile: unicode.zip

Module unicode1: Create a UTF-8 encoded file that contains these Unicode characters: Greek alpha, Greek beta, Greek gamma, Hebrew aleph.
Main.java
Module unicode2: In a Swing JPanel, display the Unicode characters Greek alpha, Greek beta, Greek gamma, Hebrew aleph.
Main.java MyFrame.java MyPanel.java

StaticMethods Project

Zipfile: static-methods.zip
No modules are defined for this project.

Class: CountDown.java Print the count down sequence for a rocket launch. The countDown method is static because it is called from a class (not called from an object).
Class: Square.java Test the square method that returns the square of its input value.
Class: Test.java Test the countdown and square methods defined in Countdown.java and Square.java, respectively.
Class: PrintPowers.java Print table of the values, squares, cubes, and 4th powers of ints from 1 to 10.
Class: Acrostic.java An acrostic is a poem arranged so that the first letters of each line have a meaning. Given an input array of strings that represent the lines of a poem, return the string composed of the first concatenated letters of the lines of the poem.
Class: WriteCheck1.java Use stepwise refinement to write helper methods to implement the details of writing the check. Print the count down sequence for a rocket launch.

InstanceMethods

Zipfile: instance-methods.zip
No modules are defined for this project.

Class: StringTest.java Test some methods and other features of the String class.
Class: CalendarTest.java Test some instance variables of a Calendar object
Class: IntegerTest.java The Integer class is called a wrapper class because it wraps an int value in an object. Test some instance methods of the Integer class.
Class: SSBCompare.java Create String objects using a loop without and with the assistance of a StringBuilder object.

UnitTests

Zipfile: unit-tests.zip
Creating a JUnit5 Test Class for IntelliJ

Module greetertest: The unittest class GreeterTest tests the makeGreeting method in the Greeter class.
Greeter.java GreeterTest.java
Module stringtest: The unittest class StringTest tests methods in the String class. No String class is included in this module; use a fake class (e.g., FakeClass) to use for creating a test class.
StringTest.java
Module phoneletters2digits: The phoneLettersToDigits method of the GetDigits class, convert letters to the digits of a phone number. The GetDigitsTest class contains unit tests for the GetDigits class method.
PhoneLetters2Digits.java PhoneLetters2DigitsTest.java
Module: amt2words The amt2Words method in the Amt2Words class inputs a double amount < 100.00 and converts it to words suitable for using as the amount on a check. The Amt2WordsTest class provides the test1 method with assertEquals statements to test the Amt2Words.amt2Words method.
Amt2Words.java Amt2WordsTest.java

Classes Project

Zipfile: classes.zip

Module person: This Person class has fields (instance variables) name, gender, and age. Getters are defined for name and gender; a getter and setter are defined for age. The haveBirthday method adds one to age.
Person.java Test1.java (Traditional Tests) Test2.java (Unit Tests)
Module counter: Implement Counter class that counts items, for example, persons, animals, items on an assembly line, etc.
Counter.java Test1.java (Traditional Tests) Test2.java (Unit Tests)
Module pet: Define Pet class with fields name, animal, vaccinated. Add constructor getters, setters, and toString method.
Pet.java Test1.java (Traditional Tests) Test2.java (Unit Tests)

InputOutput

Zipfile: input-output.zip
No modules are defined for this project.

Class: StringTest.java Test a Scanner object that reads from a string. Also use the String split method to extract the words from the same string.
Class: ReadFromWeb.java Read raw HTML lines from input file and print them to stdout.
Class: WriteGreetings.java Read names of persons from input file names.txt, then write greetings to each of them, each in its own output file.
Class: UseFileChooser.java Open an output file with a FileChooser dialog. Read names and write greetings as in the WriteGreetings class.
The input file names.txt is used for the WriteGreetings and UseFileChooser classes.

Inheritance Project

Zipfile: inheritance.zip

Module employeehierarchy: The classes in this module implement this inheritance hierarchy:
```
Person ← Employee ← Executive
```
Instance variables are set with the constructor; instance variables are read with the toString method.
Person.java Employee.java Executive.java Test1.java (Traditional Tests) Test2.java (Unit Tests)

Module shapehierarchy: The classes in this module implement this inheritance hierarchy:
```
Rectangle ← Shape → Circle
```
Instance variables are set with the constructor; instance variables are read with the toString method.
Shape.java Rectangle.java Circle.java Test1.java (Traditional Tests) Test2.java (Unit Tests)

Test3.java

Module socialnetwork: The classes in this module implement this inheritance hierarchy:
```
MessagePost ← Post → PhotoPost
```
This example stores information about a post in a social network news feed. The main part of the post consists of a (possibly multi-line) text message. Other data, such as author and time, are also stored.
Post.java MessagePost.java PhotoPost.java NewsFeed.java Test.java (Traditional Tests)

TestPackage

Zipfile: testpackage.zip
No modules are defined for this project.

Class: Counter.java Implement a Counter class according to this UML diagram. Before creating the class, add the package it313.sjost to the src folder.
Class: TestCounter.java Implement a test file to test the Counter class. The test file is not in the it313.sjost package.

JFreeChart Project

Zipfile: jfreechart.zip

jFreeChart JAR Files for this example and Project 3b:
jfreechart-1.0.19.jar jcommon-1.0.23.jar

Class: BarChart.java This Person class has fields (instance variables) name, gender, and age. Getters are defined for name and gender; a getter and setter are defined for age. The haveBirthday method adds one to age.
Class: LineChart.java Implement Counter class that counts items, for example, persons, animals, items on an assembly line, etc.

Interfaces Project

Zipfile: interfaces.zip

Module speaker: Create and test classes that implement the Speaker interface. The required method of the Speaker interface is speak.
Speaker.java Cat.java Dog.java Person.java Test1.java
Module sortable:
Person.java Test2.java

Serialization Project

Zipfile: serialization.zip

Module serialization1: Show how to serialize a single object. Run the TestOut class before running the TestIn class.
Person.java TestIn.java TestIn.java
Module serialization2: Show how to serialize an ArrayList collection. Run the TestOut class before running the TestIn class.
Person.java Employee.java Executive.java TestIn.java TestOut.java
Module serialization3: Create a programmer defined collection class, which is able to serialize its own objects.
EmployeeRoster.java Test.java

EmployeeFind Project

Zipfile: employeefind.zip

Show how to search collection for a specified substring.
Class: Employee.java Base class.
Class: Executive.java Derived class.
Class: EmployeeRoster.java User defined collection class that holds Employee or Executive objects.
Class: Test.java Test class for EmployeeRoster collection class.

PackageAccessibility Project

Zipfile: packageaccessibility.zip

Test the four kinds of accessibility: public, protected, private, package (default).
Package: it313 Classes: A.java B.java
Package: Default Classes: C.java Main.java

Patterns1 Project

Zipfile: patterns1.zip

Module: logger Illustrate the Singleton software pattern. Only one instance of a singleton class is allowed. This is accomplished by using a private constructor. Create the file c:/logger before running this example.
Logger.java Main.java
Module: reusableobjects Illustrate the Singleton software pattern.
Reusable.java Main.java
Module: factory Illustrate the Factory software pattern Make the constructor private so that objects can only be obtained using the static getInstance method.
FactoryObject.java Main.java
Module: employeefactory Illustrate the Factory software pattern. The getInstance method can create objects from three different classes.
Person.java Employee.java Executive.java EmployeeFactory.java Test.java

Observer Project

Zipfile: observer.zip

Module: observer An observable object can have one or more observers; an observer may be any object that implements interface it313.util.Observer. After an observable instance changes, an application calling the it313.util.Observable's notifyObservers method causes all of its observers to be notified of the change by a call to their update method.
Package: it313.util Classes: Observable.java Observer.java
Module: messageboard1 Illustrate the Observer software pattern. Student is the observer; MessageBoard is the observable.
Classes: MessageBoard.java Student.java Main.java
Module: messageboard2 Illustrate the Observer software pattern. In addition to the currentMessage, an archive of old messages is kept is an array list.
Classes: MessageBoard.java Student.java Main.java
Module: casino The Manager object is the observer. The SlotMachine objects are the observables.
Classes: SlotMachine.java Manager.java Main1.java Main2.java

Patterns2 Project

Zipfile: patterns2.zip

Module: iterator
StateInfo.java Test.java Input file: state-info.txt
Module: sorting1
Main.java
Module: sorting2
    Test.java
    Package: sorting
         SortAlgorithm.java InsertionSortAlgorithm.java SelectionSortAlgorithm.java QuickSortAlgorithm.java Sorter.java
Module: state
    Test.java
    Package: gumball
         State.java NoQuarterState.java HasQuarterState.java SoldState.java SoldOutState.java GumballMachine.java
Module: elevator
Test.java State.java FirstFloorState.java SecondFloorState.java StateManager.java

JDBC Project

Zipfile: jdbc.zip

JAR File Download:
https://bitbucket.org/xerial/sqlite-jdbc/downloads/

Show how to use Java Database Connectivity (JDBC) classes to create, populate, and query databases.

Class: CreateTable.java Create a simple SQL table with three columns (name, gender, age) and two rows (primary keys Alice and Bob).
Class: LoadKids.java Create the kids table and populate it from the data in the input file kids.txt.
Class: DisplayKids.java Repeatedly input an id between from 1001 to 1196 then display the name, gender, and age of the kid with that id.
Class: LoadTransactions.java Create the transactions table and populate it from the data in the input file transactions.txt.
Class: DisplayTransactions.java Repeatedly input an id between from 1001 to 5000 then display the buyer, seller, amount, and timestamp with that id.

Swing Project

Zipfile: swing.zip

Module swingcontrols: Show how to create a simple Swing frame with some controls. Look up these controls in the Java Class Library.
MyFrame.java
Module listener: A listener is added to the three buttons, which can report which button was clicked. The event handler then goes back to the button and obtain the caption from the clicked button.
MyFrame.java

Recursion Project

Zipfile: recursion.zip

Module: trace1 Practice problem: predict the output by drawing the recursion tree.
Classes: Main.java
Module: hanoi1 Solve the Towers of Hanoi Puzzle using the standard recursive algorithm.
Classes: Main.java
Module: hanoi2 Solve Towers of Hanoi puzzle graphically.
Classes: Main.java MyFrame.java MyPanel.java DiskDisplay.java
Module: floodfill Illustrate the FloodFill algorithm. The user draws a closed shape and picks a seed point in the shape. The application fills the shape with a recursive algorithm.
Classes: Main.java MyFrame.java MyPanel.java
Module: maze Compute and display the path that connects the start point to the end point. Show solution in yellow.
Classes: Main.java MyFrame.java MyPanel.java
Module: knightstour Show solution of the Knights Tour Problem: visit every square on an n x n chessboard once. A knight makes an L-shaped move.
Classes: Main.java MyFrame.java MyPanel.java
Module: fileinfo List file information in folder and all subfolders.
Classes: FileInfo.java

Module: familytree Hard code this family tree:

          +---------John 78---------------+
          |             |                |
     Arthur 56     Marjorie 54       Randolf 49
        /  \          /   \              |
       /    \        /     \             |
Jason 35 Katie 30 Barry 32 Jennifer 28 Chloe 25
     |
 Mason 10

Then print out in depth first order using a recursive algorithm.
Classes: Main.java Person.java

Module: trace2 Practice problem: Draw the recursion tree, then predict the output.
Classes: Main.java

Multithreading Project

Zipfile: multithreading.zip

Show how to use threads to add numbers in parallel. A class that implements Runnable can be run in a thread.
Classes: Adder.java Main.java

SwingGui Project

Zipfile: swinggui.zip

Use the IntelliJ GUI Form Designer to create a simple GUI form:
Creating a Swing GUI Project
Classes: MyForm.java
XML File: MyForm.form

KotlinProj Project

Zipfile: kotlinproj.zip

Look at several sample Kotlin source code files:
- Class: Hello.java The customary Hello World program in a new language.
- Class: DuckTyping.java Kotlin variable initialization.
- Class: Strings.java Various ways to represent String objects. Use """ to allow embedded line feeds.
- Class: Collections.java Create and read from an array and a hash table.
- Class: Person.java Define a Person class. Getters and setters are automatically generated.
- Class: TestPerson.java Test the Person class in Person.kt.
- Class: TestAssert.java The Kotlin require statement is reminiscent of assertEquals. It throws an exception if the statement is not true.