cleared up running instructions

README.md

@@ -1,30 +1,45 @@
 # Basic Statistics
 
-A Java-based implementation for computing statistics on a set of numbers.
+Basic Statistics is a Java-based implementation for computing statistics on a set of numbers.
 This implementation is intended to be used in software engineering courses as
 a subject software system.
 
-How to build and run tests from the terminal:
+Basic Statistics uses the Apache Ant build system. **Make sure that you have [Ant](https://ant.apache.org) installed.**
 
-1. Basic Statistics uses Apache Ant.  Make sure that you have Ant installed.  https://ant.apache.org/
+#### How to build Basic Statistics and run its tests from the terminal:
 
-2. cd into the Basic Statistics root directory, which contains the `build.xml` build file.
+1. Change into the Basic Statistics root directory, which contains the *build.xml* build file.
 
-3. Run `ant` to compile Basic Statistics.
+2. Run `ant compile` to compile Basic Statistics. The compiled class files will be in the *bin* directory.
 
-4. The compiled Basic Statistics class files will be in the `bin` directory.
+4. Run `ant test` to run all Basic Statistics unit tests.
 
-5. Run `ant test` to run all Basic Statistics unit tests.
+5. Run `ant clean` whenever you want to clean up the project (i.e., delete all generated files).
 
-6. Whenever you want to clean up the project, run `ant clean`
+#### How to run Basic Statistics from the terminal:
 
-How to run (from Terminal):
+1. After building the project (i.e., running `ant compile`), run: `java -cp bin BasicStats`. The application's GUI will show up.
 
-1. After building the project (i.e., running `ant`), cd into the `bin`
-   directory and run: `java BasicStats`. The application's GUI should show up.
+#### Program features:
+* Displays a set of entered numbers.
+* Computes the mean of the set of numbers.
+* Computes the median of the set of numbers.
+* Computes the mode of the set of numbers.
 
-Program features:
-* Displayed numbers
-* Mean computation
-* Median computation
-* Mode computation
+## Troubleshooting
+
+#### Outdated version of JUnit
+If your system uses an outdated version of JUnit, you may encounter the following error:
+```
+[junit] junit/framework/JUnit4TestAdapterCache
+[junit] java.lang.NoClassDefFoundError: junit/framework/JUnit4TestAdapterCache
+```
+Run `ant -lib lib/ <target>` to explicitly use JUnit4, which is provided in the *lib* directory. For example, run `ant -lib lib/ test` to run all Basic Statistics unit tests.
+
+#### Java JDK not installed or misconfigured
+If a Java JDK is not installed or properly configured on your system, you may encounter the following error: 
+```
+BUILD FAILED
+build.xml:17 Unable to find a javac compiler;
+```
+Make sure that you have a JDK installed and that the JAVA_HOME environment variable is properly set.