How to make a system in 25 days? ctd...

Utilizing the break...

I'm using java for coding.

Class Diagram

purpose: show the types being modeled within the system

Example of a class diagram for the class 'Flight' would look like this

Mapping a class diagram

• Packages - map to Java package names
• Classes - map directly to Java classes
• Interfaces - map to Java interfaces
• Attributes - map to Java properties and fields
• Associations, Aggregations, Compositions - map to Java references
• Operations - map to Java methods
• Generalizations - map to Java inheritance relations 
• Attributes - map to Java properties and fields  
• Attributes - map to Java properties and fields  
• Realizations - map to implementation of Java interfaces 
• Dependencies - at the most basic level these just map to Java import statements

UML Associations 

Cardinality - a cardinality of one on a given relationship end generates a Java reference

Aggregation
    Composition associations - child object can not exists with out the parent.when the parent is deleted child also is deleted when we implement in java.
    Aggregation Association - same behavior as a regular association.

One to many association



resulting code for this is something like following.

public class Customer {
  List getPurchases() {...}
  void setPurchases(List purchases) {...}
  ...
}

This link is a good reference on class diagrams
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