Our First OO Design

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Our First OO Design
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The Problem

• I want a program that will keep track of my
  appointments for me.
• The ones available don't suit me.

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I need

• dates
• events (who what where when why)
• a way to organize events
• a list?
• linked list
• list of nodes where each node has
• event
• pointer to next node

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Date

• day
• month
• year
• some ways to compare dates
• a way to display a date

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Date Class
Date Class
DAY
MONTH
MONTHLEN
the "same"s
day
the "Gets"
readDate
month
display
year
copy (Date)
boolean before (Date)
weekday
Date next(int)
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Event

• who
• what
• where
• when (a DATE)
• priority
• comment
• a way to display an event
• a way to make a new event
• a way to edit an event?

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Event Class
Event Class
EVENTS
FIRST
LAST
what
who
the "Gets"
where
priority
displayEvent
comment
when
newEvent
editEvent
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Event List

• we'll need a way to collect events..
• we'll keep a linked list of events
• each node will need a place for the event and a
  place for the link
• we'll need ways to look for events in this
  collection

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Event List Looks Like
Head
Next
Event
Event
Next
Next
EventListNode
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EventListNode Class
EventListNode Class
Event data
EventListNode next_ptr
EventListNode( Event )
EventListNode( EventListNode)
linkTo (EventListNode)
the "Gets"
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EventList Class
EventList Class
EventListNode head
count
addNode (Event)
the "Gets"
insertNode (EventListNode)
EventList findByDate(Date)
display
EventList findByEvent(int)
display (count)
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Manager

• we need something to look after this list
• IT will "own" maintain the list
• anyone wishing to get at it will have to go
  through the manager
• the manager "knows" how to display the list how
  to look for stuff in the list
• maybe we could call this an agent?

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Manager Class
Manager Class
EventList sublist
EventList sublist
Event newEvent()
displayAll
addEvent( Event )
displayPart
Event makeEvent()
EventList findEvents
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Development

• as we build we will test!
• the tester is just for that

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the tester (in MAIN)

• Date d1 new Date()
• Date d2 new Date()
• Manager listman new Manager()
• int which
• EventList temp
• System.out.print("Enter a date ")
• d1.readDate()
• d1.display()
• for (int i 0 i lt 3 i)
• Event E listman.newEvent()
• E.displayEvent()
• listman.displayAll()