Comparing objects for equality (we already know how)

  . We know how to compare primitive type data for equality testing,
    right? 

  . We also know how to compare objects for equality using '==' and
    'equals', right?

  . A couple of the methods that any Java class inherits from
    java.lang.Object 

    - equals(...)

    - toString()


Comparing objects for 'greater than', 'less than', or 'equal to'
comparisons 

  . Will introduce 'compareTo'

  . see Building.java
        UseBuilding.java

  . Would it be useful to be able to compare objects this way?

    - If you have an array of Building objects, you can sort the array
      using compareTo to compare building objects.