The design principle and best practice of the "polymer" framework in the Java class library
The polymer framework is a commonly used design pattern in the Java class library that is used to gather a set of objects to synthesize a new object.It follows some design principles and best practices to ensure the readability, maintenance and scalability of the code.
Here are the design principles and best practices of the polymer framework:
1. Single responsibility principle (SRP): Each polymer class should have a clear responsibility and only responsible for the implementation of the responsibility.The polymers should focus on the operation of specific data or logic to avoid coupling multiple responsibilities together.
2. Open-closed principle (OCP): The polymer class should be expanded to open and modify the closure.This means that the function of the system should be extended by adding a new polymer class, rather than directly modifying the existing polymer class.
3. Relying on inversion principle (DIP): The polymer should depend on abstraction rather than specific implementation.By introducing interfaces or abstract classes, polymer classes can be decoupled with concrete, thereby improving the flexibility and testability of the code.
4. Combination mode: The polymer class can use a combination mode to manage a set of objects.This means that the polymer itself can contain other objects and achieve the behavior of polymers through the operation of these objects.
5. Ididers mode: The polymer can realize the iterator interface to provide traversing and access to the internal objects of the polymer.This method can hide details inside and provide consistent access interfaces.
6. Draft Principles (LKP): The polymer should minimize dependence on other classes.It should only interact with those direct -related classes and try to avoid tightly coupled with irrelevant classes.
The following is the code of a sample polymer type:
public interface Component {
void operation();
}
public class ConcreteComponent implements Component {
@Override
public void operation() {
System.out.println("Performing operation in ConcreteComponent");
}
}
public class Composite implements Component {
private List<Component> components = new ArrayList<>();
public void add(Component component) {
components.add(component);
}
public void remove(Component component) {
components.remove(component);
}
@Override
public void operation() {
System.out.println("Performing operation in Composite");
for (Component component : components) {
component.operation();
}
}
}
public class Client {
public static void main(String[] args) {
Component component1 = new ConcreteComponent();
Component component2 = new ConcreteComponent();
Composite composite = new Composite();
composite.add(component1);
composite.add(component2);
composite.operation();
}
}
In the above example, the Component interface defines the operation method of the polymer.The Concretecomponent class is specific component implementation.The Composite class implements the Component interface and uses a list to manage a set of Component objects.The client class creates a composite object by creating a component object and adding them to the Composite object to use the polymer framework.
To sum up, the design principles and best practice of the polymer framework aim to maintain the flexibility, scalability and maintenance of the code.By following these principles, developers can better organize the relationship between and manage objects, thereby improving the quality and readability of the code.
