Notes - 03/20   

Class discussion

Lab from yesterday.  Thinking like a computer scientist.

• The Comparable interface allowed us to use our HolidayAccount object array in the Array.sort method.  We could not have done so otherwise.
• Issues - The interface must be implemented with the exact signature of the interface.  
• Since HolidayAccount was not "recognized" as being an object, we had to create another method with the signature and then one specific to HolidayAccount or cast the "other" object as a HolidayAccount object.
• Both are messy.
• Maybe there is a better way.  Here is what I saw when looking at the documentation for the sort method...http://java.sun.com/j2se/1.5.0/docs/api/java/util/Arrays.html#sort%28java.lang.Object%5B%5D%29
• And how I followed the links to arrive at a more elegant solution to the problem.

Activities

• Worksheet.  First, think back to Monday's lab and share solutions.
• Think about the nature of abstract classes, inheritance, and interfaces.
• Explore the model of classes.
• Answer some questions to predict how the compiler or the JVM will react to various statements.
• Create your own questions.