This diagram shows a use case with an ‘include’ relationship, indicating a use case that is always executed in another use case.
This diagram illustrates a use case with an ‘extend’ relationship, representing optional or conditional behavior.
Generalization in use case diagrams is used to show inheritance between actors or use cases.
public class Car {
private String color;
private String make;
private String model;
private int year;
private boolean isConvertible;
private double engineCapacity;
public Car(String color, String make, String model, int year, boolean isConvertible, double engineCapacity) {
this.color = color;
this.make = make;
this.model = model;
this.year = year;
this.isConvertible = isConvertible;
this.engineCapacity = engineCapacity;
}
private boolean startEngine() {
// Implementation
return true;
}
public String drive(String direction, int speed) {
// Implementation
return "Driving " + direction + " at " + speed + "mph";
}
public boolean park(int level, String spot) {
// Implementation
return true;
}
public boolean toggleConvertible() {
// Implementation
return isConvertible = !isConvertible;
}
public void stopEngine() {
// Implementation
}
public void honk(int times) {
// Implementation
for (int i = 0; i < times; i++) {
// Honking logic
}
}
}Describes how many instances of one class can be associated with instances of another class.
Example:
Example:
Example:
Example:
Note: In this diagram, both Dog and Cat classes override the makeSound() method from the Animal class, demonstrating polymorphism.
Example:
Promotes reusability and scalability in your system design.
Changes in the superclass propagate to subclasses, simplifying maintenance.
Example:
Constraints ensure that the system adheres to certain conditions, rules, or limitations. Often expressed in natural language or a more formal language like OCL (Object Constraint Language).
A ‘Car’ must have a ‘make’ and ‘model’ before it can be ‘sold’.
Diagram:
An ‘Order’ can’t be ‘shipped’ unless it’s been ‘paid’.
Object diagrams are snapshots of the instances in a system at a particular moment. They are akin to class diagrams but focus on instances (objects) rather than classes.
Components:
Objects with names and states.
Links representing relationships between instances.
public class System {
public String processRequest(String data) {
// Process the data
return "Response";
}
}
public class User {
public static void main(String[] args) {
System system = new System();
String data = "Data";
String response = system.processRequest(data);
System.out.println("Received response: " + response);
}
}“Essentially, the makePayment message is sent from a Register instance to a Sale instance, which then creates a Payment instance. Here, ‘message’ means a method call.”
This diagram represents an e-commerce system with packages for different functionalities, including ‘Customer’ interactions, ‘Payment Gateway’ handling, and ‘Product Catalog’ management. Arrows illustrate dependencies between classes and packages for functionality and data exchange.
Overview: This diagram represents key stages in a user account’s life cycle, including creation, suspension, reactivation, and closure.
Decomposition Description: The “Check Inventory” step in the e-commerce order processing can be decomposed into detailed sub-steps such as “Verify Item Availability,” “Reserve Item,” and “Update Inventory Status.”
Process Description: Author creates, Reviewer reviews, Approver approves.
