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The Midway software design pattern

#designpatterns #java #architecture #oop 
# 🧙‍♂️ The Midway Software Design Pattern: A New Software Design Pattern for Controlled Access  ---  ## 🧠 What Is the Midway Method? The Midway Method is a newly proposed software design pattern that introduces a clean, reusable way to restrict access to private behavior based on contextual trust. It's ideal for situations where you want to expose sensitive functionality — but only to a select group of objects. Think of it as a gatekeeper inside your class. Instead of exposing a private method directly, you expose a midway method that checks whether the caller is trusted, and only then delegates to the private logic.  ---  ## 🎯 Problem It Solves Languages like Java don't support fine-grained access control beyond public/private/protected. What if you want:  - A method that's private, but accessible to specific objects? - A way to validate callers before executing sensitive logic? - A clean alternative to reflection, friend classes, or exposing too much? The Midway Method solves this by creating a controlled access point inside your object.  ---  ## 🧩 Pattern Structure **Components**  - **Host**: The object that owns the private method and the midway method - **Guest**: An object that may request access - **Trusted List**: A list of guests allowed to invoke the private method - **Midway Method**: A public method that checks trust and delegates  ---  ## 🛠️ Java Example
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java
public interface Guest {
void requestAccess(Host host);
}
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java
public class Host {
private List trustedGuests = new ArrayList<>();

public void addGuest(Guest guest) { trustedGuests.add(guest); } private void secretMethod() { System.out.println("Secret method accessed!"); } void grantAccess(Guest guest) { if (trustedGuests.contains(guest)) { secretMethod(); } else { System.out.println("Access denied."); } }
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}
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java
public class VIPGuest implements Guest {
@override
public void requestAccess(Host host) {
host.grantAccess(this);
}
}
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java
public class Demo {
public static void main(String[] args) {
Host host = new Host();
Guest guest1 = new VIPGuest();
Guest guest2 = new VIPGuest();

 host.addGuest(guest1); guest1.requestAccess(host); // ✅ Secret method accessed! guest2.requestAccess(host); // ❌ Access denied. }
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}

 --- ## 🧬 Why It's a Pattern The Midway Method isn't just a coding trick — it's a repeatable architectural solution: - ✅ Enforces contextual trust - ✅ Keeps sensitive logic encapsulated - ✅ Avoids exposing internal behavior - ✅ Works across languages and platforms It's especially useful in: - 🔐 Secure plugin systems - 🎮 Game mechanics (e.g., allies triggering buffs) - 🧠 AI modules with internal trust networks --- ## 🧙‍♂️ Origin Story This pattern was first described by Moti Barski, who built a system where only objects in a list attribute could access a private method of the containing class. It wasn't documented anywhere — not in the Gang of Four, not in Fowler's catalog — making it a new contribution to software architecture. --- ## 🧠 Final Thoughts The Midway Method is a simple but powerful way to go beyond basic access control. It's not just composition — it's intentional trust-based delegation. If you've ever needed to expose behavior selectively, this pattern might be your new favorite tool. --- What do you think? Could this pattern evolve into something bigger — like dynamic trust levels or encrypted method calls? Drop your thoughts below 👇
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