• Intent: decoupling parts of an object to a sublcass in order to avoid combinatorial explosion
  • Decouples abstraction from its implementation so that the two can vary indepedently
  • You have a Abstraction that takes in any Implementor, and you have an Implementor that can work with any (register in the BaseClass) Abstraction
• Components
  • Abstraction (the what) ⇒ client-facing interface
    • Contains reference to Implemntor which executes the actual work
    • High-level
    • Extends Abstraction for the customized version of a given subject
  • Implementation (the how) ⇒ functionality to be given for the Abstraction (contains several ones)
    • Low-level
    • You can have several ones
  • Bridge ⇒ via object composition
• Use-case
  • Decoupling the what from the how
  • When you have MxN problem (where M is subject/abstraction and N is functionality/implementor)
• Notes
  • Difference to Factory is that factory is concerned of the proper object creation based on factory instance, whereas bridge defines a different relationship in the structure of the object (not in its creation).
    • Factory decouples client request for an object from how its instantiated
    • Brige decouples abstraction from implementation
• Code

QUESTIONS

• What is object composition?
  • In comparision with inheritance (is-a relationship), object composition (has-a relationship) aims to create complex objects by being built out of small subobjects (that are specialized)
• What is a primitive?
  • Fundamental data type used to build more complex interfaces
• I dont understand hierahchy of class nor refined abstraction