What is Spring Proxy and why does it not create a wrapper around private methods?

Spring Proxy is a mechanism that creates proxy objects to manage bean behavior, for example, to implement aspect-oriented programming (AOP).

Proxies are created based on interfaces (JDK Proxy) or classes (CGLIB), and they intercept method calls to add additional logic.

Why doesn't a proxy create a wrapper around private methods?

• Proxies work through method overriding or interface implementation, and for this, methods must be visible externally (public or protected).
• Private methods are not accessible outside the class, so proxies cannot override or intercept calls to them.
• Calls to private methods within the class are not routed through the proxy but are called directly.

Example:

@Service
public class MyService {
    public void publicMethod() {
        privateMethod(); // direct call, without proxy
    }

    private void privateMethod() {
        // this logic will not be proxied
    }
}

Thus, Spring Proxy cannot handle private methods because they are not accessible for overriding, and calls are made directly within the class.