Proxy Pattern

Proxy wraps an object so access can be controlled, delayed, protected, or redirected while keeping the same client-facing contract.

In Java, proxy is practical because many systems need one of these behaviors:

• lazy creation of an expensive object
• access control around a resource
• local stand-in for a remote service
• instrumentation around interface calls

Proxy is not just “a wrapper.” The point is that the wrapper stands in for the real object and changes how access to it happens.

In this section

• Implementing Proxy in Java
  Implement Java proxies by preserving the original contract while controlling access, creation, or invocation of the real object.
• Types of Proxies in Java
  Distinguish virtual, protection, and remote proxies in Java so the access concern is explicit instead of buried in a generic wrapper.
• Dynamic Proxies in Java
  Use Java dynamic proxies when cross-cutting behavior should wrap many interface implementations without hand-writing one proxy class per type.
• Proxy vs. Decorator Pattern
  Compare Proxy and Decorator in Java so access control and optional behavior layering are not treated as the same design move.
• Proxy Pattern Use Cases and Examples in Java
  See where Proxy genuinely helps in Java systems, from remote clients and security wrappers to lazy loading and caching access boundaries.