Using the cs220utils Package

Java allows classes to be grouped into packages; for example, the package java.util contains general java utilities such as the Scanner and Random classes, and the package java.awt contains graphics/windowing classes. We often import these packages when we want to use one or more of their classes; if we didn't, we would have to prefix the class name with the package name every time we used it (e.g., java.util.Scanner scan = new java.util.Scanner(System.in)).

Pre-existing Java packages start with "java.", but users can also create their own packages. For example, I have created a package called cs220utils where I can put classes for you to use. This keeps everyone from having to copy the classes I provide, which would be a nuisance and a waste of space, and would pave the way for having numerous slightly different versions of common utilities -- usually not a good idea. Instead I'll put these utilities in a single package, you'll tell the Java system where to look for it, and then import it as needed. To access these classes you need to do the following:

Tell Java where to find the cs220utils package, which means modifying your classpath. Open file .bashrc (don't forget the leading .) in your home directory; if you don't have such a file, create a new one. Add the following line (anywhere; at the bottom is fine) EXACTLY as written here (case matters!):
```
export CLASSPATH=$CLASSPATH:/home/department/cpsc/cs220
```
If there is already a line like this (export CLASSPATH=$CLASSPATH:...) in your .bashrc, just add :/home/department/cpsc/cs220 to the end of it.
This is a one-time thing. Every time you start a new shell, .bashrc gets executed and the classpath is updated.
Now any time you want to use a class in cs220utils, just import cs220utils.ClassYouWant. So for the first project, you will put the following at the top of your file that uses the FileScanner;
```
import cs220utils.FileScanner;
```
If in the future you want access to all of the classes in the package, just import cs220utils.*.