Reflect4 Proxies -

The upcoming SOCKS6 protocol specification includes native UDP multiplexing and explicit packet length fields. Once SOCKS6 is widely adopted, the need for custom Reflect4 proxies may diminish. However, as of 2025, SOCKS5's UDP support remains fragmented, making custom raw UDP proxies the only reliable option.

This operates at Layer 2 (Ethernet). It simply forwards frames from Reflect4 to the target and back. Pros: Invisible to the target OS. Cons: Requires physical adjacency or virtual Ethernet (veth) pairs. Used primarily in lab environments.

In JavaScript, Proxy and Reflect are twin features introduced in ES6. A fascinating analysis might cover:

import net.bytebuddy.ByteBuddy;
import net.bytebuddy.implementation.MethodDelegation;
import net.bytebuddy.matcher.ElementMatchers;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.atomic.AtomicLong;
public class MethodCounterProxy 
public static <T> T withCounters(T delegate, Class<T> type) 
MethodCounter counter = new MethodCounter();
T proxy = new ByteBuddy()
.subclass(type)
.method(ElementMatchers.isDeclaredBy(type))
.intercept(MethodDelegation.to(counter).andThen(MethodDelegation.to(delegate)))
.make()
.load(type.getClassLoader())
.getLoaded()
.getDeclaredConstructor()
.newInstance();
// Store counters if needed
return proxy;

static class MethodCounter 
    private final ConcurrentHashMap<String, AtomicLong> counts = new ConcurrentHashMap<>();
@RuntimeType
    public void count(@Origin Method method) 
        counts.computeIfAbsent(method.getName(), k -> new AtomicLong()).incrementAndGet();
public long getCount(String methodName) 
        return counts.getOrDefault(methodName, new AtomicLong()).get();

Unlike JDK proxies, Byte Buddy can proxy concrete classes.

Example target class (no interface needed):

public class UserService 
    public String getUserName(Long id) 
        return "User_" + id;
public void saveUser(String name) 
    System.out.println("Saving: " + name);

Creating a proxy that logs method calls:

import net.bytebuddy.ByteBuddy;
import net.bytebuddy.implementation.MethodDelegation;
import net.bytebuddy.matcher.ElementMatchers;
public class ProxyDemo 
public static void main(String[] args) throws Exception 
UserService original = new UserService(); reflect4 proxies
    UserService proxy = new ByteBuddy()
        .subclass(UserService.class)
        .method(ElementMatchers.any())
        .intercept(MethodDelegation.to(new LoggingInterceptor()))
        .make()
        .load(UserService.class.getClassLoader())
        .getLoaded()
        .getDeclaredConstructor()
        .newInstance();
proxy.getUserName(123L);  // Logs + original logic
    proxy.saveUser("Alice");

Interceptor:

import net.bytebuddy.implementation.bind.annotation.*;
public class LoggingInterceptor 
@RuntimeType
public static Object intercept(@Origin Method method,
@AllArguments Object[] args,
@SuperCall Callable<?> zuper) throws Exception 
System.out.println("Entering: " + method.getName());
try 
Object result = zuper.call();
System.out.println("Exiting: " + method.getName());
return result;
 catch (Exception e) 
System.out.println("Error: " + e);
throw e;

| Problem | Solution | |--------|----------| | java.lang.NoClassDefFoundError: net/bytebuddy/... | Add Byte Buddy dependency | | Cannot proxy final class | Byte Buddy can’t subclass final classes; use defineClass with a ClassLoadingStrategy that redefines | | IllegalAccessError on method | Ensure interceptor method has @RuntimeType and proper visibility | | Constructor invocation fails | Provide explicit ConstructorStrategy or default constructor | "Reflect4" could be a shorthand for "Reflect for

Q: Can I use a free proxy list for Reflect4? A: Absolutely not. Free proxies are overloaded, log aggressively, and almost universally block UDP. You will achieve 0% success.

Q: Does Reflect4 support HTTP CONNECT proxies? A: Only for TCP-based modules. For UDP reflection, no. You must use udp_raw or socks5_udp.

Q: How many Reflect4 proxy nodes do I need for a large-scale test? A: The Reflect4 framework performs best with a 1:1 client-to-proxy ratio. For 10 Gbps of reflection traffic, deploy 10 proxy nodes (each with 1 Gbps uplink) and load-balance Reflect4 threads across them.

Q: Will Cloudflare or Akamai block my Reflect4 proxy? A: Yes. They utilize "IP reputation scoring." If your proxy IP sends malformed UDP packets at high velocity, it will be null-routed within minutes. Use residential Reflect4 proxies (extremely rare and expensive) or rotate proxies every 60 seconds.

For functions and constructors:

const loggingHandler = 
  apply(target, thisArg, args) 
    console.log(`Called with args: $args`);
    return Reflect.apply(target, thisArg, args);
  ,
  construct(target, args) 
    console.log(`Constructed with $args`);
    return Reflect.construct(target, args);
;
function Greeting(name) 
this.name = name;
 import net
const ProxyGreeting = new Proxy(Greeting, loggingHandler);
const obj = new ProxyGreeting("Alice"); // Constructed with Alice