The class discussion board is hosted on Piazza. In addition to being an important forum for discussing material, we make all course announcements through piazza.

• Read the instructions for using piazza. They are complicated because posting code to piazza is a bit of a pain, but it works well once you learn the system. Don't worry if you don't understand everything yet. You can always find these instructions by clicking the Piazza link in help menu, and they will make more sense as the semester progresses.
• Click the following link piazza sign up to sign up for the class message board.

This part of the homework will walk you through setting up the necessary software on your computer, and making sure that it works. The software you need is all freely available, and the booksite provides a handy installer to set it up for you. Even if you have already installed Java on your computer, you need to complete this step to set up the course-specific software properly. The necessary tools are also installed on the Moore lab computers, but you will need a SEAS account to log in. If you are an engineering student, you should already have a SEAS account.

Non-SEAS Students: Request your SEAS account here - . It usually takes at least 30 minutes for your account to be activate. Even if you do not plan on using the lab computers, you should request an account now. If your own laptop stops working for any reason, you will be relieved to have immediate access to the lab machines. (Per SEAS policy, SEAS accounts are available only to registered students (including P/F), but not to auditors.)

This part of the homework walks you through completing your first program. Traditionally, the first program anyone writes in a new language just prints, "Hello, World."

• Create a folder for your CIS 110 homework. You may want to place this on your desktop (but back it up constantly!), or you may wish to put it in your Penn+Box or DropBox account (but make sure it is private and not shared with anyone!). Students suffer computer failures every week, and we cannot grant extensions in these cases.
  
  
• Create a folder named hw00 inside your CIS 110 homework folder. You will place all your files for Homework 0 in the hw00 folder. You will create similar folders for each future assignment.
  
  
• Open Dr. Java. The introcs installer should have created a shortcut on your desktop for you. The following program exactly as it appears below, except that you should update the name, PennKey, and recitation at the top. If you haven't been assigned a recitation yet, just put ???. Type the program, do not copy and paste it, just for practice (it won't take long). If you omit even a semicolon, the program won't work.
  
  As you type, Dr. Java does the indenting for you.
  
  

  /*  Name: Benedict Brown
   *  PennKey: bjbrown
   *  Recitation: 200
   *
   *  Execution: java HelloWorld 
   *
   *  Prints "Hello, World". By tradition, this is everyone's first program.
   *
   */
  
  public class HelloWorld {
  	public static void main(String[] args) {
  		System.out.println("Hello, World");
  	}
  }
  	      

• Click the Compile button in Dr. Java's toolbar to translate your program into a form the machine can execute. If you have any errors (like forgetting a semi-colon), you may get an error. The message will likely seem cryptic at this stage, but it will tell you which line of code has a problem. Click on the error to highlight the line, and make sure you typed in exactly the program above.
  
  
• Click the Run button in the toolbar to run your program. It should print out, "Hello, World" in the interactions pane at the bottom of the window.

For CIS110, we will be using a drawing library that we have called PennDraw (PennDraw is StdDraw that the textbook refers to with some additional functionality)
To do this part of your HW:

1. Download PennDraw.java and put it in your hw folder.
2. Open this up in DrJava.
3. Click Compile in the DrJava toolbar.
4. Click Run in the DrJava toolbar.
5. You should see a drawing appear in a new window. If so, close the window and continue with the assignment. If not, we'll be happy to help you.

Here is some example code to make sure that drawing is working on your machine. It also gives you some examples of what can be drawn using PennDraw.
PennDraw is documented extensively on the PennDraw wiki

Make sure to update the header section so that it is your name, PennKey, and recitation (or ??? if you don't have a recitation yet). Make sure this code runs on your machine and pay attention to the comments in the code. Those should help you understand how the program works. Save this file as MyHouse.java .

 /**
 * Name : Arvind Bhusnurmath
 * PennKey : bhusnur4
 * Recitation : 110
 * 
 * Execution: java MyHouse
 *
 * An example drawing using the PennDraw library
 * This draws a house in the middle of a green field with a blue sky.
 */
	  
public class MyHouse {
    public static void main(String[] args) {
        PennDraw.setCanvasSize(500, 500);
        // draw a blue background
        PennDraw.clear(PennDraw.BLUE); 
        
        //draw a green field
        PennDraw.setPenColor(0, 170, 0);
        PennDraw.filledRectangle(0.5, 0.25, 0.6, 0.3);
        
        //change the pen color to a shade of yellow
        PennDraw.setPenColor(200, 170, 0);
       
        //draw a filled triangle (roof)
        PennDraw.filledPolygon(0.255, 0.70, 0.745, 0.70, 0.49, 0.90);
        
        //draw the house
        PennDraw.filledRectangle(250 / 500.0, 260 / 500.0, 120 / 500.0, 
                                 90 / 500.0);
        
        PennDraw.setPenRadius(0.005); // thicken the pen for outline drawing
        
        PennDraw.setPenColor(PennDraw.BLACK); // make the pen black
        
        // draw the roof outline        
        PennDraw.polygon(0.255, 0.70, 0.745, 0.70, 0.49, 0.90); 
        
        // draw the house outline
        PennDraw.rectangle(250 / 500.0, 260 / 500.0, 120 / 500.0, 90 / 500.0);
        
        // draw the door outline
        PennDraw.rectangle(298 / 500.0, 220 / 500.0, 40 / 500.0, 50 / 500.0);
        
        PennDraw.point(270 / 500.0, 220 / 500.0); // draw a doorknob
    }
}

Design and create your own piece of digital art using Java and the PennDraw library. Think of yourself as a creative designer when choosing the topic of your design. This is your very first program, so here are some guidelines:

• Make a header section with your name, pennkey etc similar to what you have done in HelloWorld and in MyHouse.
• Make sure that it is at least 500 pixels by 500 pixels. The dimensions can vary depending upon your design, but make sure that it is not "small".
• Make use of any of the drawing primitives learned in class this week: setCanvasSize, rectangle, filledRectangle etc.
• You are also allowed to use any of the drawing primitives that you find on the PennDraw wiki.
• Your sketch should make use of several functions (as this is the point of this assignment!. A really "abstract" sketch like a simple circle in the center of the screen will not suffice, as aesthetic as it may seem).

• Build your program up slowly, compiling and testing it frequently as you go.
• Start by adding a few simple shapes to your sketch. Then test your program. Then change the colors. Then test it. Then add some more, and test it. Repeat this process, building your program up step-by-step.
• At each point in time, you should have a completely working program. If you made a small change and broke something, then most likely the problem is in what you just changed. This makes debugging faster and easier.
• Trying to write a bunch of code and then debugging it all at once will result in frustration and a program that is difficult to get working.
• Be creative. Have fun and experiment!

Here are some ideas to get you started:

• A self-portrait
• An avatar or a cartoon of someone
• Your favorite cartoon TV Show character, or design your own...
• A city scape
• Animal/object caricatures/study

• Right-click readme_hello.txt and save the link to your hw00 folder.
• In Dr. Java, select File|Open. At the bottom of the open dialog, select Files of Type: All Files. Now you can open the readme_hello.txt file you just saved in Dr. Java.
• Complete all questions in readme_hello.txt and save the file. You will submit it with everything else in the next step.
• Warning: Always edit the readme files in Dr. Java. Never use Notepad, TextEdit, Word, or any other non-programming editor. These programs will all corrupt the file, and we won't be able to read your submitted version. There will typically be a significant deduction for submitting a corrupted readme, because it makes your TAs lives very difficult when they try and grade your assignment. (Don't worry: we're lenient about this on the first couple of assignments.)

• Click "SCORES/SUBMIT" in the course menu bar.
• Log in with your PennKey.
• Select task hw00 and click the submit button.
• Upload HelloWorld.java, MyHouse.java, MySketch.java, and readme_hello.txt using the provided form.
• Click "Submit" to submit your homework. Save the submission receipt as your proof of submission.
• Your file names should match the required exactly, file names including capitalization. Java is extremely picky about file names and capitalization; if your file name doesn't match what we expect, your program will probably fail our automated tests. It may also be a sign that you submitted the wrong file (e.g. HelloWorld.class instead of HelloWorld.java). You can always re-submit to correct such errors.
• The confirmation page shows you the recorded submission time, which files have just been uploaded, which were previously uploaded, and which have not yet been submitted.
• Read the Test Output section carefully. We show you the results of a variety of automatic tests on every homework. Each homework will describe the tests it runs. Usually, we will show you the output of compiling your program on our servers (if you program compiles correctly, there will be no warning or error messages), a few simple tests, and the results of checkstyle.
• The tests we run on your submission are not complete, and do not guarantee your program works perfectly. On some homework, we only show you the result of compiling on our servers
• checkstyle automatically checks your program for conformance to many aspects of our coding style guidelines. It is not exhaustive. See the "Coding Style" section of the policies for more information.
• All homework must be submitted through the submissions system. We cannot accept e-mailed submissions.

• Compress the .java files along with all image files needed to run the program into a single zip file. The exact instructions to create a zip file will vary depending on your operating system; please post to Piazza if you need help.
• Call the file extra.zip and submit it along with your other files using the instructions above.
• You can test your zip file to make sure it included all necessary files by (1) moving it to a new directory, (2) uncompressing it, and (3) compiling and running your programs from the extracted files.