FAQs

This page will be updated frequently. Start at this page if you have a problem.

Installation

A JNI error has occured....: This error occurs usually when there are multiple version of java installed. Try to uninstall all java and installing again.

Common errors

… expected

This error occurs when something is missing from the code. Often this is created by a missing semicolon or closing parenthesis.

unclosed string literal

This commonly happens when the string literal does not end with quote marks. This is easy to correct by closing the string literal with the needed quote mark.

cannot find symbol

This is a common error when the compiler cannot find the identifier. Some of the main cause of this issue can be:

The spelling of the identifier when declared may not be the same as when it is used in the code.
The variable may not have been declared.
The variable may be out of scope.

Incompatible types

This is an error in logic when an assignment statement tries to pair a variable with an expression of types. For example: if you try to assign an int to a string variable.

Error class is public, should be declared...

This error occurs when the filename doesn't match the class name.

Git

How do I add files to git?

Make sure you are inside your git folder (Gitlab folder). Once you are in there, use the following commands:

git add filename
git commit -m "Commit message"
git push origin master

How do I clone a project?

Use git clone "git link". More on this in the resource page.

What is authentication error when trying to clone?

This error message means you have entered the wrong password. Try to clone again with the correct password. It might not show typing when hitting password although it is getting registered. For Windows users once you see Authentication failure you should be following the steps mentioned below:

From start menu, search for "Credential Manager" and select it.
Then click on "Windows Credentials"
Under "Generic Credentials", remove your credential of gitlab.cs.uno.edu
Then go to your gitlab account. Always sign in using "UNO Active Directory Login"
Go to settings of your gitlab account and the change password
Now follow the cloning process and type in your correct UNO username and password that you have recently changed.
You should be able to clone a repository in your local machine.

How can you push all your java files together?

So, it is important that your gitlab repository is as clean and organized as possible. While you work on your local repository, you might have all .class files and handin.zip files in it. you should be uploading only your java files to gitlab. You can do that by following the steps mentioned below:

git add *.java
git commit -m "Your message over here. Type in relevant message that will help you back track your submissions"
git push origin master

Autolab

How do I submit to autolab?

To submit to autolab, compress all your work (java files) into a zip file named "handin.zip" Go to autolab.cs.uno.edu and click on the lab under 1581. You can drag and drop the handin file or click and select the file. You will get your grades within a few minute of submission.

I have my code give correct output, but autolab is only giving me 2 points.

The most common error while submitting to autolab are:

Check for the new line character (\n). Usually, when using printf, you might have forgot to append a new line character.
You should not print any additional output than that is given to you. This means you should not print any prompt messages such as Enter a number. If the pdf handout shows only a number as output, your program should print the output only.
Sometimes, you might have forgotten to print your answer. Double check your solution for correct output before submitting.