OODP

CS680: Object Oriented Design and programming

Singleton Design Pattern

• Purpose: Ensures that a class has only one instance and provides a global point of access to it.
• Implementation: A private constructor, a static method to get the instance, and a static field to store the single instance.

Static Factory Method Pattern

• Purpose: Uses a static method to create objects, offering more flexibility compared to constructors.
• Implementation: Multiple static methods to return different object types.

JUnit Testing

• Purpose: Focuses on testing object behaviors using JUnit framework.
• Implementation: Tests Singleton and Factory methods using JUnit assertions.

State Design Pattern

• Purpose: Implements the State pattern to allow an object to change its behavior when its internal state changes.
• Implementation: Encapsulates state-related behaviors into separate classes and dynamically switches between these states at runtime.

Template Method Pattern

• Purpose: Uses the Template Method pattern to define the steps of an algorithm while allowing subclasses to override certain steps.
• Implementation: Provides a skeleton of the algorithm in a base class, with abstract methods for customization in subclasses.

Composite Design Pattern

• Purpose: Demonstrates the Composite pattern to handle tree structures where individual objects and compositions are treated uniformly.
• Implementation: Provides a uniform interface for both composite and leaf nodes, allowing recursive object structures.

Proxy Design Pattern

• Purpose: Implements the Proxy pattern to control access to an object by providing a surrogate or placeholder.
• Implementation: The proxy class controls access to the original object, adding an extra level of abstraction to manage access and enhance security or performance.

Iterator Design Pattern

• Purpose: Demonstrates the Iterator pattern to provide a way to sequentially access elements in a collection without exposing the underlying structure.
• Implementation: Uses iterator interfaces to traverse collections like arrays or lists.

Visitor Design Pattern

• Purpose: Implements the Visitor pattern to separate algorithms from the objects on which they operate.
• Implementation: The visitor class defines operations that can be performed on elements in a collection, without modifying the elements themselves.

Strategy Design Pattern

• Purpose: Uses the Strategy pattern to define a family of algorithms, encapsulate each one, and make them interchangeable.
• Implementation: Allows the algorithm to be selected at runtime, promoting flexibility without altering the client code.

Comparators in Java API and Pareto Comparison

• Purpose: Demonstrates the use of Java’s Comparator interface and Pareto comparison for sorting and comparing objects.
• Implementation: Uses lambda expressions to streamline comparison logic and achieve more concise code.

Null Object Design Pattern

• Purpose: Implements the Null Object pattern to avoid explicit null checks and provide a default behavior.
• Implementation: Returns a neutral object that adheres to the expected interface but does nothing, improving code cleanliness and reducing null-related errors.

Here’s the final breakdown for the last three homework assignments:

Functional Programming and Lambda Expressions in Java

• Purpose: Demonstrates the use of functional programming techniques and lambda expressions for writing cleaner and more concise code.
• Implementation: Replaces anonymous classes with lambda expressions and applies functional interfaces to simplify callback methods and other logic.

Observer and Multicast Design Patterns

• Purpose: Implements the Observer pattern to manage state changes and updates across multiple objects, while multicast allows multiple listeners to receive updates.
• Implementation: Efficiently handles event propagation and state synchronization between observers.

Command Design Pattern

• Purpose: Uses the Command pattern to encapsulate actions as objects, allowing for flexible command execution.
• Implementation: Supports undo/redo functionality by encapsulating operations and separating command execution from requesters. Here’s the breakdown for the last two homework assignments:

Callback Methods and Lambda Expressions

• Purpose: Focuses on using callback methods and lambda expressions to simplify asynchronous operations.
• Implementation: Implements callbacks using functional interfaces and lambda expressions for cleaner, more efficient asynchronous programming.

Command Pattern with Multicast

• Purpose: Builds on the Command pattern by integrating multicast to handle multiple receivers of commands.
• Implementation: Demonstrates the command execution across multiple listeners, enabling flexible and dynamic command handling with multicast.