Creating a JAR File

Once you have successfully completed your programming assignment, you will need to create a JAR file to submit your assignment. This will help us grade your assignment. You will lose points if you do not submit your programming assignments in a JAR file.

Instructions for checking your JAR file

What is a JAR File?

JAR stands for "Java Archive." It is much like a compressed ZIP file that you may have used before. You will be adding each Java source file in your assignment (usually only one file, sometimes more) to a JAR file before submitting. The size of the final JAR file will be smaller than the original programs and therefore be easier to e-mail.

How Do I Create a JAR File?

After you've successfully compiled, run, tested, and commented your program, choose New...Standard Project from the Project menu in jGRASP.
You will be presented with a dialog box where you will name your project. You can name it anything you want, but for consistency, I recommend naming it yourlastname_assign#.gpj (for example, kohli_lab1.gpj or kohli1_prg1.gpj). After you have named your project, click Create.
You will be offered the opportunity to add files to the project. Select the first .java file you would like to add to the project, and then click Add. Repeat this for each .java file you would like to add to the project.

Then click Close.

You should then see your project open in jGRASP, as below.

Choose Create JAR File For Project from the Project menu in jGRASP.
The Create JAR File for Project dialog box should open. Make sure the only checkbox that is checked on is labeled Sources. The other checkboxes should be off. The .java files that you added earlier should appear as shown below. If they do not, click Add to add your .java files for the current assignment. Click Next.
A new dialog box will open asking for the name of the JAR file to create. You should name the file yourlastname_assign#.jar (for example, kohli_lab1.jar or kohli_prg1.jar). Make sure that the JAR file ends in .jar and that the file is being created in the same folder as your Java source files. Once you have appropriately named your JAR file, click Create JAR.

How Do I Check to Make Sure My JAR File is Correct?

After you've completed the steps above, your JAR file should appear in the list of files on the left side of your jGRASP window.
Choose JAR/Zip Extractor from the Project menu.
In the JAR/Zip Extractor window, click on the folder icon.
In the Open File dialog box that appears, chose the JAR file that you just created and click Open.

If you see the names of your Java source files in the JAR/Zip Extractor window, you have successfully created your JAR file. (You may also see some other files, like "META-INF" and "MANIFEST.MF" in the window.) Double-check the Modified date to make sure that you've put the latest version of your Java source file in the JAR file. You can now close the JAR/Zip Extractor window.